RxPG News : Psychology

Self-affirmation may break down resistance to medical screening

Thu, 22 Dec 2011 23:00:00 PST

( from http://www.rxpgnews.com ) People resist medical screening, or don't call back for the results, because they don't want to know they're sick or at risk for a disease. But many illnesses, such as HIV/AIDS and cancer, have a far a better prognosis if they're caught early. How can health care providers break down that resistance?

Have people think about what they value most, finds a new study by University of Florida psychologists Jennifer L. Howell and James A. Shepperd. If you can get people to refocus their attention from a threat to their overall sense of wellbeing, they are less likely to avoid threatening information, says Howell. Do that, and people are more likely to face a medical screening even if it means undertaking onerous treatment and even if the disease is uncontrollable. The findings will appear in Psychological Science, a journal published by the Association for Psychological Science.

The researchers undertook three studies, each with about 100 students of both sexes. In all three studies, they asked the participants to think of a trait they valued; they chose traits such as honesty, compassion, and friendliness. Participants then wrote either about how they demonstrated the trait (expressing self-affirmation) or a friend (not affirming themselves) demonstrated the trait.

Next participants watched a video about a (fictional) disorder called thioamine acetlyase (TAA) deficiency that ostensibly impairs the body's ability to process nutrients and can lead to severe medical complications. They then completed an online risk calculator for the disease and decided either to receive their risk feedback or not.

In the first study, fewer participants who wrote self-affirming essays avoided learning their risk than did participants who wrote non-affirming essays. In studies 2 and 3 researchers investigated the effects of affirmation on two conditions known to increase avoidance of risk feedback. In the second study, participants learned that testing at high risk for TAA deficiency would either require an easy or onerous follow-up examination process. Participants who were not affirmed avoided learning their risk more when they thought it might necessitate an onerous, as compared to an easy, follow up. However, affirmed participants showed little avoidance regardless of the difficulty of follow up. In the third study, participants learned either that TAA could be managed with a pill; or that there was no effective treatment. Again, the non-affirmed group avoided learning their risk almost twice as often when hearing they had no control over the illness. By contrast, affirmed participants were unlikely to avoid the news, regardless of the possibility of treatment.

The researchers acknowledge it’s sometimes rational to choose not to know about an incurable disease you might (or might not) get. “But when it is important to prepare for negative events—getting your affairs in order, finding the coping resources you’ll need,” Howell suggests, going through with that screening might wise.

Faster progress through puberty linked to behavior problems

Thu, 01 Sep 2011 04:00:00 PST

( from http://www.rxpgnews.com ) Children who go through puberty at a faster rate are more likely to act out and to suffer from anxiety and depression, according to a study by researchers at Penn State, Duke University and the University of California, Davis. The results suggest that primary care providers, teachers and parents should look not only at the timing of puberty in relation to kids' behaviour problems, but also at the tempo of puberty -- how fast or slow kids go through puberty.

Past work has examined the timing of puberty and shown the negative consequences of entering puberty at an early age, but there has been little work done to investigate the effects of tempo, said Kristine Marceau, a Penn State graduate student and the study's primary author. By using a novel statistical tool to simultaneously model the timing and tempo of puberty in children, we present a much more comprehensive picture of what happens during adolescence and why behaviour problems may ensue as a result of going through these changes.

The team -- led by Elizabeth Susman, the Jean Phillips Shibley Professor of Biobehavioral Health at Penn State -- created a unique nonlinear mixed-effects model that incorporated data from 364 white boys and 373 white girls that had been collected as part of the National Institute of Child Health and Human Development's Study of Early Child Care and Youth Development, which had an initial goal of determining how variations in the environment are related to children's development. The data included information about breast and pubic hair development in girls and genital and pubic hair development in boys as assessed by nurses, as well as weight and height for both boys and girls. The data also included information on internalizing and externalizing behaviour problems as reported by boys' and girls' parents or other caregivers, and risky sexual behaviours as reported by the kids themselves.

We found that earlier timing for girls was related to a slew of behaviour problems, and we also found that a faster tempo of development independently predicted those same sorts of problem behaviours, said Marceau. Although timing and tempo both predicted behaviour problems in girls, timing and tempo weren't related to each other. For boys, though, we found a strong relationship between timing and tempo. For example, we found that boys who have later timing combined with slower tempo exhibited the least amount of acting out and externalizing problems.

The team's results will appear in the September issue of the journal Developmental Psychology.

Why does going through puberty at a faster rate relate to external behavior problems and internal anxiety and depression?

"The thought is that when the major changes of puberty are compressed into a shorter amount of time, adolescents don't have enough time to acclimate, so they're not emotionally or socially ready for all the changes that happen," said Marceau. "This is the explanation that originally was attributed solely to early timing, but we suggest that the same thing also is happening if the rate of puberty is compressed."

According to Susman, timing and tempo of puberty vary dramatically across kids. "Children are extremely sensitive to how fast or slow other kids are going through puberty, and that may contribute to both the internalizing depression-type problems or the externalizing problems of acting out," she said.

In the future, Susman plans to examine the effects of tempo of puberty on later women's health problems. "One of the things that has concerned me over the years is the relationship between early puberty and later women's health problems," she said. "Specifically, there is some indication that early timing of puberty relates to more reproductive cancers, with the speculated mechanism being estradiol. If you're an early maturer, you have a longer exposure to this hormone. The question is whether the tempo of puberty has similar implications for women's health."

Experience vital for complex decision-making

Wed, 20 May 2009 11:31:46 PST

( from http://www.rxpgnews.com ) Experience is vital when we have to make complex decisions based on uncertain or confusing information, a new study has found.

'Learning from experience actually rewires our brains so that we can categorise the things we are looking at, and respond appropriately to them,' said Zoe Kourtzi from the University of Birmingham, who led the research.

In selecting a course of action that is most likely to be successful, the brain has to interpret and ascribe meaning to inherently uncertain information - being able to do this is vital for our survival.

This ability is critical when we are responding to visual stimuli that are very similar - for example, trying to recognise friends in a crowd or discern a tumour from healthy tissue on a medical scan.

'We have shown that this learning process is not just a matter of learning the structure of the physical world - when I look at something I'm not just playing a game of 'snap' in my head where I try to match images to each other,' Kourtzi said.

'In fact, areas in our brains are actually trained to learn the rules that determine the way we interpret sensory information,' he said, according to a university statement.

Kourtzi and colleagues wanted to find out about the human brain mechanisms that mediate flexible decision-making through learning, which have so far not been well understood, despite it being fairly clear that successful decisions benefit from previous experience.

They combined measurements of behaviour and brain signals to study how volunteers learned to discriminate between highly similar visual patterns and to assign them in different categories.

The research was published in Wednesday's edition of Neuron.

Decreased Dopamine processing ability - cause for high risk behaviour?

Wed, 31 Dec 2008 08:31:47 PST

( from http://www.rxpgnews.com ) For risk-takers and impulsive people, New Year's resolutions often include being more careful, spending more frugally and cutting back on dangerous behavior, such as drug use. But new research from Vanderbilt finds that these individuals--labeled as novelty seekers by psychologists--face an uphill battle in keeping their New Year's resolutions due to the way their brains process dopamine. The research reveals that novelty seekers have less of a particular type of dopamine receptor, which may lead them to seek out novel and exciting experiences--such as spending lavishly, taking risks and partying like there's no tomorrow.

The research was published Dec. 31, 2008, in the Journal of Neuroscience.

The neurotransmitter dopamine is produced by a select group of cells in the brain. These dopamine-producing cells have receptors called autoreceptors that help limit dopamine release when these cells are stimulated.

"We've found that the density of these dopamine autoreceptors is inversely related to an individual's interest in and desire for novel experiences," David Zald, associate professor of psychology and lead author of the study, said. "The fewer available dopamine autoreceptors an individual has, the less they are able to regulate how much dopamine is released when these cells are engaged. Because of this, novelty and other potentially rewarding experiences that normally induce dopamine release will produce greater dopamine release in these individuals."

Dopamine has long been known to play an important role in how we experience rewards from a variety of natural sources, including food and sex, as well as from drugs such as cocaine and amphetamine. Previous research has shown that individuals differ in both their number of dopamine receptors and the amount of dopamine they produce, and that these differences may play a critical role in addiction. Zald and his colleagues set out to explore the connection between dopamine receptors and the novelty-seeking personality trait.

"Novelty-seeking personality traits are a major risk factor for the development of drug abuse and other unsafe behaviors," Zald and his colleagues wrote.

"Our research suggests that in high novelty-seeking individuals, the brain is less able to regulate dopamine, and this may lead these individuals to be particularly responsive to novel and rewarding situations that normally induce dopamine release," Zald said.

Previous research in rodents showed that some respond differently to novel environments. Those who explore novel environments more are also more likely to self-administer cocaine when given the chance. Dopamine neurons fire at a higher rate in these novelty-responsive rodents, and the animals also have weak autoreceptor control of their dopamine neurons. Zald and colleagues speculated that the same relationships would be seen in humans.

The researchers used positron emission topography to view the levels of dopamine receptors in 34 healthy humans who had taken a questionnaire that measured the novelty-seeking personality trait. The questionnaire measured things such as an individual's preference for and response to novelty, decision-making speed, a person's readiness to freely spend money, and the extent to which a person is spontaneous and unconstrained by rules and regulations. The higher the score, the more likely the person was to be a novelty seeker.

The researchers found that those that scored higher on the novelty-seeking scale had decreased dopamine autoreceptor availability compared to the subjects that scored lower.

Stimulating scalp with weak current improves dexterity

Mon, 03 Nov 2008 14:57:44 PST

( from http://www.rxpgnews.com ) Washington, Nov 3 - Stimulating the scalp with weak current and underlying motor regions of the brain could make you more skilled at delicate tasks.

New research shows that a non-invasive brain-stimulation technique, transcranial direct current stimulation -, is able to improve the use of a person's non-dominant hand.

Gottfried Schlaug and Bradley Vines from Beth Israel Deaconess Medical Centre - and Harvard Medical School, tested the effects of using tDCS over one or both sides of the brain on 16 healthy, right-handed volunteers, as well as testing the effect of simply pretending to carry out the procedure.

'The results of our study are relevant to clinical research on motor recovery after stroke,' said Schlaug.

Volunteers were not aware of which of the three procedures they were receiving. The test involved using the fingers of the left hand to key in a series of numbers displayed on a computer screen, according to a BMC press release.

The results were striking; stimulating the brain over both the right and left motor regions - resulted in a 24 percent improvement in the subjects' scores.

This was significantly better than stimulating the brain only over one motor region or using the sham treatment -.

tDCS involves attaching electrodes to the scalp and passing a weak direct current through the scalp and skull to alter the excitability of the underlying brain tissue.

The treatment has two principal modes depending on the direction in which the current runs between the two electrodes. Brain tissue that underlies the positive electrode - becomes more excitable and the reverse is true for brain tissue that underlies the negative electrode -.

No relevant negative side effects have been reported with this type of non-invasive brain stimulation. It is not to be confused with electroconvulsive therapy, which uses currents around a 1,000 times higher.

These findings are scheduled for publication in BMC Neuroscience.

Psychiatrist warns about impact of social networking sites

Sat, 12 Jul 2008 04:44:39 PST

( from http://www.rxpgnews.com ) A generation of Internet users who have never known a world where you can't surf on-line may be growing up with a different and potentially dangerous view of the world and their own identity, according to a warning delivered to the Annual Meeting of the Royal College of Psychiatrists.

Dr Himanshu Tyagi, a psychiatrist at West London Mental Health Trust, said that people born after 1990, who were just five-years-old or younger when the use of Internet became mainstream in 1995, have grown up in a world dominated by online social networks such as Facebook and MySpace.

”This is the age group involved with the Bridgend suicides and what many of these young people had in common was their use of Internet to communicate. It's a world where everything moves fast and changes all the time, where relationships are quickly disposed at the click of a mouse, where you can delete your profile if you don't like it and swap an unacceptable identity in the blink of an eye for one that is more acceptable,” said Dr Tyagi. “People used to the quick pace of online social networking may soon find the real world boring and unstimulating, potentially leading to more extreme behaviour to get that sense.

”It may be possible that young people who have no experience of a world without online societies put less value on their real world identities and can therefore be at risk in their real lives, perhaps more vulnerable to impulsive behaviour or even suicide. This is definitely a line of reasoning that warrants more investigation and
research.”

Dr Tyagi became interested in factors shaping an online identity when he founded an online professional network by the name of RxPG (Prescription for Professional Growth) which is now subscribed by more than 60,000 medical graduates and undergraduates worldwide. He warned the meeting that there was a massive generation gap amongst current psychiatrists and young patients around the Internet related issues. A survey of International psychiatrists conducted by him at a recent psychiatric conference in US showed that the vast majority of psychiatrists worldwide were unaware of the full magnitude of impact of online world on the younger generation.

Chat room communication was also more likely to encourage disinhibition because of anonymity, and involve reduced sensory experience: “If you can't see the person's expression or body language or hear the subtle changes in their voice, it shapes your perceptions of the interaction differently,' Dr Tyagi said.

A session in front of the computer was also likely to create “an altered perception, a
dream-like state, an unnatural blending of their mind with the other person – something that rarely happens in real life. The new generation raised alongside internet is attaching an entirely different meaning to friendship and relations, something we are largely failing to notice”.

Dr Tyagi said there were significant benefits for the online social networking. It provides an equalised status where wealth race and gender were less meaningful; a loss of geographical boundaries which meant that opportunities to access unrestricted peer support are abundant, which can be important in maintaining good psychological health for many. He said: “No one is a pariah on net, it works great in
flattening the hierarchies of the real world.”

But Dr Tyagi warned that while many people today cannot remember a world without the Internet, it may be “quite different for teens and children who cannot imagine a world where you can't go online to talk and apply the same principles to real-world interpersonal communications, mostly to a dysfunctional outcome. It's vital that we
face up to what is happening. The Internet will not go away so these issues, which would inevitably grow in magnitude with time, need to be addressed soon.”

Study shows how context dictates what we believe we see

Fri, 22 Feb 2008 07:21:30 PST

( from http://www.rxpgnews.com ) Scientists at UCL (University College London) have found the link between what we expect to see, and what our brain tells us we actually saw. The study reveals that the context surrounding what we see is all important – sometimes overriding the evidence gathered by our eyes and even causing us to imagine things which aren’t really there.

The paper reveals that a vague background context is more influential and helps us to fill in more blanks than a bright, well-defined context. This may explain why we are prone to ‘see’ imaginary shapes in the shadows when the light is poor.

Eighteen observers were asked to concentrate on the centre of a black computer screen. Every time a buzzer sounded they pressed one of two buttons to record whether or not they had just seen a small, dim, grey ‘target’ rectangle in the middle of the screen. It did not appear every time, but when it did appear it was displayed for just 80 milliseconds (80 one thousandths of a second).

“People saw the target much more often if it appeared in the middle of a vertical line of similar looking, grey rectangles, compared to when it appeared in the middle of a pattern of bright, white rectangles. They even registered ‘seeing’ the target when it wasn’t actually there,” said Professor Zhaoping, lead author of the paper. “This is because people are mentally better prepared to see something vague when the surrounding context is also vague. It made sense for them to see it – so that’s what happened. When the target didn’t match the expectations set by the surrounding context, they saw it much less often.

Demonstration of Inferences of Objects from Images (A) and (B) show two images containing the same white patch, and (C) and (D) show the two possible inferred objects in the scene causing this white patch. The inferred causes for any particular input image patch is not unique, although some inferences are more likely than others. The difference in the most likely inferred object for the same image patch in (A) and (B) demonstrates that inference could be greatly influenced by the image context.

“Illusionists have been alive to this phenomenon for years,” continued Professor Zhaoping. “When you see them throw a ball into the air, followed by a second ball, and then a third ball which ‘magically’ disappears, you wonder how they did it. In truth, there’s often no third ball - it’s just our brain being deceived by the context, telling us that we really did see three balls launched into the air, one after the other.

“Contrary to what one might expect, it is a vague rather than a bright and clearly visible context that most strongly permits our beliefs to override the evidence and fill in the blanks. In fact, a bright and clearly visible context actually overrides the evidence in the opposite direction - suppressing our ‘seeing’ of the vague target even when it is present.

“Mathematical modelling suggests that visual inference through context is processed in the brain beyond the primary visual cortex. By starting with a relatively simple experiment such as this, where visual input can be more easily and systematically manipulated, we are gaining a better understanding of how context influences what we see. Further studies along these lines can hopefully enable us to dissect the workings behind more complex and wondrous illusions.”

Loneliness could be bad for health

Sun, 19 Aug 2007 14:38:28 PST

( from http://www.rxpgnews.com ) New York, Aug 19 - Loneliness could be bad for your health, psychologists in the US have warned.

University of Chicago psychologists Louise Hawkley and John Cacioppo studied a group of college-age individuals and adults aged 50 to 68 to reach the conclusion.

When the psychologists looked at the lives of the middle-aged and old people in their study, they found that although the lonely ones reported the same number of stressful life events, they identified more sources of chronic stress and recalled more childhood adversity.

When faced with similar challenges, the lonelier people appeared more helpless and threatened. And ironically, they were less apt to actively seek help when stressed out.

The psychologists took urine samples from both the lonely and the more contented volunteers, and found that the lonely ones had more of the hormone epinephrine flowing in their bodies.

Epinephrine is one of the body's 'fight or flight' chemicals, and high levels indicate that lonely people go through life in a heightened state of arousal, reported science portal EurekAlert.

As with blood pressure, this physiological toll likely becomes more apparent with aging. Since the body's stress hormones are intricately involved in fighting inflammation and infection, it appears that loneliness contributes to the wear and tear of aging through this pathway as well.

When people experience stress, the bodies normally rely on restorative processes like sleep to shore up. But when the researchers monitored the younger volunteers' sleep, they found that the lonely nights were disturbed by many 'micro awakenings.'

The findings of the study appeared in the Aug issue of Current Directions in Psychological Science, a journal of the Association for Psychological Science.

The researchers, however clarified that loneliness is not the same as solitude. Some people are just fine with being alone, and some even see solitude as an important path to spiritual growth.

Do I know you? QBI researchers identify woman's struggle to recognize new faces

Mon, 23 Jul 2007 04:00:00 PST

( from http://www.rxpgnews.com ) The woman's condition, known as prosopamnesia, is extremely rare and has only been found in a handful of people around the world, according to University of Queensland cognitive neuroscientist Professor Jason Mattingley.

ï¿½For many years, scientists have been interested in how people learn to recognise new faces, and people who have difficulty with faces often have trouble interacting in social settings,ï¿½ he said.

The woman ï¿½ whose identity remains protected ï¿½ presented herself to researchers after experiencing social embarrassment when she found she was unable to recognise colleagues, people to whom she had already been introduced.

The research, in collaboration with colleagues at Macquarie and La Trobe universities, is published in this month's edition of Current Biology. The work suggests the woman's disability might lie in her inability to encode or recognise new faces, rather than her ability to perceive them.

ï¿½She reports relying heavily on featural cues such as hair colour and style, eyeglasses, and eyebrows to recognise new acquaintances,ï¿½ Professor Mattingley said.

On a battery of standard face-recognition tests, the woman consistently registered scores that indicated her ability to recognise new faces was severely impaired.

The woman experiences a similar difficulty in recognising characters on television, but after months of repeated viewing could slowly learn to identify key individuals.

For example, when the woman was shown 42 images of pre-nominated movie celebrities, she correctly identified nine-out-of-10 of the faces.

The researchers also noted that it was only after six months of testing that the woman was able to recognise the faces.

The group's findings were backed up by brain-imaging investigations, which indicated that the woman's exposure to an unfamiliar face, even over ï¿½multiple encoding episodes', was not enough to leave a lasting memory.

ï¿½It may be that enduring face representations are slow to form or are degraded in quality, or they may decay rapidly following normal encoding,ï¿½ Professor Mattingley said.

While face recognition is currently thought to be an innate capacity that human babies have at birth, aspects of this ability are probably shaped by experience.

Prosopamnesia is probably a condition linked to an irregularity during neural development, Professor Mattingley said.

To add to the researchers' intrigue, the young woman has reported that some of her family members experience similar problems with face memory.

ï¿½If this is true, this woman's condition might present us with tantalising evidence for a genetic link as well,ï¿½ Professor Mattingley said.

While more studies are planned, the woman has placed any additional investigations on hold until she establishes her career.

STAMP system can help medical professionals to predict violence

Wed, 20 Jun 2007 21:00:00 PST

( from http://www.rxpgnews.com ) A researcher who spent nearly 300 hours observing patients in an accident and emergency department has developed a method for identifying possible flashpoints, according to the latest Journal of Advanced Nursing.

Lauretta Luck, who carried out her research at the University of Western Sydney, Australia, points out that the STAMP violence assessment framework could have much wider applications than just hospitals.

The five-month research project was carried out in a 33-bedded emergency department in a public hospital serving a large rural, remote and metropolitan community in Australia.

It serves a multi-cultural community, which includes a high number of tourists and seasonal workers as well as a large metropolitan population.

Luck carried out 290 hours of observation and interviewed 20 Registered Nurses who agreed to take part in the study.

"During my time in the department there were 16 violent episodes aimed at staff taking part in the study," says Luck. "Because I was on the spot I was able to obtain feedback from them while the event was still fresh in their minds. They were able to tell me how they perceived the event and how they tried to handle it.

"Many more episodes were observed during the study period and I was keen to note how staff managed to defuse potentially violent episodes".

âViolence towards healthcare staff and other professionals such as police officers and social security staff are an increasing part of daily lifeâ says Luck.

âWe feel that the STAMP system provides an easy to remember checklist that can be used in a wide range of potentially stressful situations to provide an initial indication of possible violence.

âRecognising the early signs that can lead to a violent episode can give staff the time they need to defuse the situation before it escalates.

âSTAMP also provides a basic framework that can be developed by healthcare organisations and other agencies â using research, observation and experience - to meet their own specific needs.â

New Insights Into the Nature of Pride as a Social Function

Mon, 18 Jun 2007 16:00:00 PST

( from http://www.rxpgnews.com ) Pride has perplexed philosophers and theologians for centuries, and it is an especially paradoxical emotion in American culture. We applaud rugged individualism, self-reliance and personal excellence, but too much pride can easily tip the balance toward vanity, haughtiness and self-love. Scientists have also been perplexed by this complex emotion, because it is so unlike primary emotions like fear and disgust.

University of British Columbia psychologist, Jessica Tracy, and Richard Robins of the University of California, Davis, have been exploring the origins and purpose of pride, both in the laboratory and in the field. They wanted to know if pride is as universal as, say, joy or anger.

In the June issue of Current Directions in Psychological Science, a journal of the Association for Psychological Science, Tracy and Robins review several recent studies on the nature and function of pride.

In one experiment, researchers used photographs of models with varying facial expressions and body language, asking subjects to identify the nonverbal signs of pride. And they did indeed find a prototypical prideful look, which was recognized by children as young as four, and people in many different cultures, including members of an isolated, preliterate tribe in Burkina Faso, West Africa.

So, pride appears to be universal, but that still leaves the question: What is it What is its purpose To explore this, Tracy and Robins first asked people to come up with words that they associated with pride. They found that either people link pride to such achievement-oriented ideas as accomplishment and confidence (authentic pride) or, people connect pride to self-aggrandizement, arrogance and conceit (hubristic pride).

People who tend to feel authentic pride were more likely to score high on extraversion, agreeableness, genuine self-esteem and conscientiousness. However, those who tend to feel hubristic pride were narcissistic and prone to shame. Further, they found that people who felt positive, achievement-oriented feelings of pride viewed hard work as the key to success in life, whereas hubristic people tended to view success as predetermined, due to their stable abilities.

Tracy and Robins argue that the primitive precursors of pride probably motivated our ancestors to act in altruistic and communitarian ways, for the good of the tribe, and the physical display of pride both reinforced such behavior and signaled to the group that this person was worthy of respect. So individual pride, at least the good kind, contributed in important ways to the survival of the community.

But what about pride's dark side Tracy and Robins speculate that hubris might have been a social "short cut", a way of tricking others into paying respect when it was not warranted. Those who could not earn respect the old-fashioned way figured out how to look and act accomplished in order to gain status. Social cheaters puffed themselves up because deep down they did not have what it took to succeed in their world. Whatever respect they got would have been fleeting, of course, as it is today

Girls Select Partners Who Resemble Their Dads - Research

Thu, 14 Jun 2007 17:00:00 PST

( from http://www.rxpgnews.com ) Women who enjoy good childhood relationships with their fathers are more likely to select partners who resemble their dads research suggests.In contrast, the team of psychologists from Durham University and two Polish institutions revealed that women who have negative or less positive relationships were not attracted to men who looked like their male parents.

Due to be published in the July issue of Evolution and Human Behaviour, the study investigated evidence of parental sexual imprinting, the sexual preference for individuals possessing parental characteristics, in women. The team used facial measurements to give a clear view of how fathers' facial features relate directly to the features of faces their daughters find attractive.

The study helps shed further light on how we choose partners and the impact of a parent's role in this process, which until recently researchers believed to be a passive one. It adds to growing theories that suggest sexual imprinting is an active process which involves the relationship between the child and the adult upon whom they imprint. This reveals the importance of parental relationships in partner selection, which could move studies in areas like evolutionary biology, fertility and genetics a step forward and offer new insights in areas such as relationship counselling and psychology.

Author Dr Lynda Boothroyd of Durham University explains: "While previous research has suggested this to be the case, these controlled results show for certain that the quality of a daughter's relationship with her father has an impact on whom she finds attractive. It shows our human brains don't simply build prototypes of the ideal face based on those we see around us, rather they build them based on those to whom we have a strongly positive relationship. We can now say that daughters who have very positive childhood relationships with their fathers choose men with similar central facial characteristics to their fathers."

Well known "daddies' girls" such as Nigella Lawson and Zoe Ball back up these findings. A comparison of pictures of Charles Saatchi with Nigel Lawson and Norman Cook with Johnny Ball reveals some close correlations, especially in the central facial area, including the nose, chin and eyes.

The study used a sample of 49 Polish eldest daughters. Each chose the most attractive face from 15 distinct faces, whose ears, hair, neck, shoulders and clothing were not visible, removing any external influences which could potentially skew results. The male stimuli's facial measurements were taken and compared with each daughter's father's measurements, so that the researchers knew which faces correlated most closely with the fathers' faces.

The daughters were asked to rate their paternal relationships looking at areas such as how much a father engaged in bringing up his daughter, how much leisure time he spent with her and how much emotional investment she received from him. These scores then made up an overall "positivity" score.

The benefits of social contact

Mon, 21 May 2007 04:00:00 PST

( from http://www.rxpgnews.com ) Have you ever wondered why people surrounded by friends or family appear happier and healthier? University of Virginia psychologist James Coan will set out to answer this question when he addresses the Association for Psychological Science's annual convention in Washington, DC, May 24th-27th.

Coan's research lies at the intersection of social psychology and neuroscience and is sure to provide intriguing insights into how social contact promotes health and well being by focusing on the function of social regulation when responding with emotions to a wide array of life's stressors.

His presentation will explore the social regulation of neural circuits responsive to fear, using an experimental paradigm that blends functional neuroimaging with supportive social interaction and emotional stress.

Mapping attention, memory and language links in human brain

Sun, 20 May 2007 04:00:00 PST

( from http://www.rxpgnews.com ) A University of Arizona scientist who has specialized in studying how fireflies and other creatures communicate has won a million-dollar grant to conduct a pioneering 5-year study on the roles that attention and memory play when the human brain hears and processes spoken language.

This is the chance to study the ultimate form of animal communication -- language, said Thomas A. Christensen of UA's department of speech, language and hearing sciences (SLHS). Humans have evolved a very sophisticated symbolic form of communication. Language affects how we think, what we believe, how we interact with each other. I'd even go so far as to say that our future as a species depends on understanding how we communicate. But very little is known about what's going on in the brain when we're having a simple conversation.

Until recently, Christensen was a research scientist with the Arizona Research Laboratories' Division of Neurobiology, studying olfactory communication (the sense of smell) in insects. His research is grounded in the areas of learning and memory, systems physiology and animal communication. Encouraged by Elena Plante, head of the SLHS department, he applied for a $1 million career development award from the National Institute of Deafness and Other Communication Disorders. The grant was awarded in April.

The grant will take his career -- and biomedical science -- in new directions. Christensen will use UA's state-of-the-art magnetic resonance imaging (MRI) facilities to map the areas and networks within the brain linked to language, attention and memory. The UA's advanced MRI is a non-invasive imaging tool that is sensitive enough to show exactly what parts of the brain are involved when a person listens to another human voice.

What you read in the text books is that if you're right handed, then language is localized to the left hemisphere of your brain, Christensen said. I found out right away -- that's just not true. Analyzing a human voice also involves the right hemisphere and even parts of the cerebellum. The cerebellum is a large part of the brain that serves to coordinate voluntary movements, posture, and balance in humans.

These MRI images destroy the myth that you're only using about 10 percent of your brain for any particular task, Christensen said. The crux of this grant is to learn more about the language, attention and memory centers in the brain, and also about the complex interactions between them.

Inside the scanner, volunteer subjects don headphones and perform simple language discrimination tasks in Christensen's experiments. They're asked to respond by pressing a button when they hear words that fall into a certain semantic category -- the name of an animal, for example. Then, to make the task a bit harder, subjects are asked to respond only when they hear a woman's voice speak a word in the chosen category. The task taxes attention even more when subjects are asked to respond to a woman's voice speaking a 'target' word in one ear at the same time a man's voice is speaking words in the other.

The MRI scanner records activity throughout the 45-minute sessions, revealing multiple regions and networks, some deep within the brain, that scientists didn't suspect were involved when the brain listens.

We're getting a snapshot of what that activity is across the population. What's so striking is how clearly we see that certain areas of the brain are strongly engaged in attentional control while other areas are not. As we scan more volunteers, we're definitely beginning to see a pattern here.

Christensen's research on the brain-governing system we called attention -- how the brain selects only some information from its environment and is able to focus awareness on objects and events relevant to immediate goals -- is profoundly relevant to such disorders as schizophrenia, ADHD and many other impairments that affect language abilities.

ADHD (Attention Deficit Hyperactivity Disorder) is probably one of the most over-diagnosed disorders of our time, Christensen said. The reason for that, I think, is that we really don't know very much about the biological basis of this syndrome. There's a lot of research on it, but there's still a lot of disagreement about what the root cause is, and about whether drugs like Ritalin that are being prescribed to children as young as 2 years old are doing any good, and if we have any business exposing our children to drugs at such a very early age, he added.

As Christensen collects more MRI data that show the connections among areas of the brain that are strongly engaged in language tasks, he plans to collaborate with computer modeling experts. We could develop a mathematical model that would allow us to generate hypotheses about what we expect if we deliver a certain type of stimulus. We'd see what effect it would produce in our model.

Simulating brain activity in the mathematical model would take the whole question of language processing beyond 'blobology' -- where you're just looking at blobs of activation in the brain. That's what I hope to do, Christensen said.

Gender and Income Does Determine Cognitive Function

Fri, 18 May 2007 04:01:09 PST

( from http://www.rxpgnews.com ) There are limited gender differences in cognitive function than previously thought. Income does affect cognitive performance but less than expected when only healthy children are considered. And while basic cognitive skills steadily improve in middle childhood, they then seem to level off questioning the idea of a burst of brain development in adolescence.

The analysis, led by Deborah P. Waber, PhD in the Department of Psychiatry at Children's Hospital Boston, focused on cognition and behavior in healthy 6- to 18-year-olds enrolled at Children's and five other metropolitan areas across the United States. Population-based sampling techniques used U.S. Census data to ensure demographic diversity. A rigorous screening process eliminated children with medical, neurologic or psychiatric disorders, familial risk factors for such disorders, or prenatal exposure to toxic substances, providing a glimpse of how a healthy brain develops.

"This report and many others that will follow provides a comprehensive set of benchmark values that clinicians and scientists studying brain development can reference for many years to come," said NIH Director Elias A. Zerhouni, MD.

From an initial sample of more than 35,000 target families, the researchers were able to enroll approximately 450 children, of whom 385 were 6 years or older. Once enrolled, the children underwent MRI scans of the brain and completed a battery of behavioral and cognitive tests to ascertain their overall IQ, verbal ability, mental processing speed, spatial ability, memory, fine motor dexterity, psychosocial function, reading and calculation ability, and other measures of cognitive function. Most have returned two more times so that their development can be tracked.

Overall, this healthy group performed better than previously reported norms. However, analysis of the first wave of data also found that boys performed better on perceptual analysis, and girls performed better on processing speed and motor dexterity. Girls also showed a slight advantage on verbal learning, but by adolescence, this advantage had disappeared.

Lower income was associated with lower IQ scores (mean IQs were 105, 110, and 115 for low-, middle- and high-income children respectively). Lower-income children were more likely to be excluded from the study because of medical or developmental conditions; the healthy low-income children who qualified performed, on average, better than previously reported population averages. "We were pleasantly surprised by how well the lower-income children did when we focused on those who were healthy," says Waber. Although income did not predict performance on basic cognitive tasks, such as memory or reading individual words, lower-income children did score lower on tests like reading comprehension and calculation. The authors suggest that such tasks, which require more reasoning and integration of cognitive abilities, are more vulnerable to the effects of poverty-related factors than are more basic skills.

Performance climbed steeply from age 6, but leveled off overall for most tests between 10 and 12 years of age, then improved more slowly or not at all during adolescence. Waber cautions, however, that these data are "snapshots" at a single point in time, averaging the performance of a whole population. "We don't know whether everyone's performance improves more slowly in adolescence, or whether some children continue to improve while others do not, or whether our standard tests can measure what really changes in adolescence," she notes. "As we follow these children over time, we will have a better understanding of what happens in adolescence."

"In the past, studies of structural brain development and often studies of cognitive development were performed on samples of convenience that weren't necessarily representative of the overall population," Waber adds. "This study provides information on a much more diverse and representative sample, and a much larger one than previously available."

Other components of the NIH MRI Study of Normal Brain Development are structural brain imaging with MRI, magnetic resonance spectroscopy (MRS), and diffusion tensor imaging (DTI) to study the growth of different brain structures and the formation of connections between them, and even changes in brain chemistry. The ultimate goals of the project are to provide an atlas of the development of the healthy child's brain and to link the imaging findings with neurobehavioral function.

Sex Differences are also Reflected in Brain

Fri, 11 May 2007 04:18:02 PST

( from http://www.rxpgnews.com ) When male primates tussle and females develop their social skills it leaves a permanent mark â on their brains. According to research published in the online open access journal BMC Biology, brain structures have developed due to different pressures on males and females to keep up with social or competitive demands.

An international research team consisting of Patrik Lindenfors, Charles Nunn and Robert Barton examined data on primate brain structures in relation to traits important for male competition, such as greater body mass and larger canine teeth. The researchers also took into account the typical group size of each sex for individual primate species in order to assess sex-specific sociality - the tendency to associate with others and form social groups. The researchers then studied the differences between 21 primate species, which included chimpanzees, gorillas, and rhesus monkeys, using statistical techniques that incorporate evolutionary processes.

The authors found that sexual selection had an important influence on primatesâ brains. Greater male-on-male competition (sexual selection) correlated with several brain structures involved with autonomic functions, sensory-motor skills and aggression. Where sexual selection played a greater role the septum was smaller, and therefore potentially exercised less control over aggression.

In contrast, the average number of females in a social group correlates with the relative size of the telencephalon (or cerebrum), the largest part of the brain. The telencephalon includes the neocortex, which is responsible for higher functions such as sensory perception, generation of motor commands and spatial reasoning. Primates with the most sociable females evolved a larger neocortex, suggesting that female social skills may yield the biggest brains for the species as a whole. Social demands on females and competitive demands on males require skills handled by different brain components, the authors suggest. The contrasting brain types, a result of behavioural differences between the sexes, might be a factor in other branches of mammalian brain evolution beyond anthropoid primates, too.

Abstinence Education Does Not Impact Sexual Behavior

Sat, 14 Apr 2007 08:28:09 PST

( from http://www.rxpgnews.com ) A recent study of four abstinence education programs finds that the programs had no effect on the sexual abstinence of youth. But it also finds that youth in these programs were no more likely to have unprotected sex, a concern that has been raised by some critics of these programs. The study found that youth in the four evaluated programs were no more likely than youth not in the programs to have abstained from sex in the four to six years after they began participating in the study. Youth in both groups who reported having had sex also had similar numbers of sexual partners and had initiated sex at the same average age.

âThis is the first study of multi-year abstinence programs, and it is one of the few that has tracked its sample members for as long as six years,â notes Christopher Trenholm, the project director and a senior researcher at Mathematica. âThe study finds that the sexual abstinence of students in four programs selected for the study was much the same as that of students who did not participate in these programs.â

âSome policymakers and health educators have criticized the Title V, Section 510 abstinence education programs, questioning whether the focus on abstinence puts teens at risk of having unprotected sex,â says Barbara Devaney, one of the study's principal investigators and vice president and director of Human Services Research at Mathematica. âThe evaluation findings suggest that this is not the case. Participants in the abstinence education programs and nonparticipating youth had similar rates of unprotected sex at first intercourse and over the past 12 months.â

The study findings highlight the challenges faced by programs aiming to reduce adolescent sexual activity. Two lessons are important for future programming in this area:

Targeting youth at young ages may not be sufficient. Most Title V, Section 510 abstinence education programs are implemented in upper elementary and middle schools and most are completed before youth enter high school. The findings from this study provide no evidence that abstinence programs implemented at these grades reduce sexual activity of youth during their high school years. However, the findings provide no information on the effects programs might have if they were implemented in high school or began at earlier ages but continued through high school.

Peer support for abstinence erodes during adolescence. Peer support for abstinence is a significant predictor of later sexual activity. Although the four abstinence programs had at most a small impact on this measure in the short term and no impact in the long term, this finding suggests that promoting support for abstinence among peer networks should be an important feature of future abstinence programs.

The study used the most rigorous, scientifically based approach to measure the impacts of the programs. Much like a clinical trial in medicine, this approach compares outcomes for two statistically equivalent groupsâa program group and a control groupâcreated by random assignment (similar to a lottery). Youth in the program group were eligible to receive the abstinence education program services, while those in the control group were not, and received only the usual health, family life, and sex education services available in their schools and communities. When coupled with sufficiently large sample sizes, longitudinal surveys conducted by independent data collectors, and appropriate statistical methods, this design is able to produce highly credible estimates of the impacts of the programs being studied.

Youth were enrolled in the study sample over three consecutive school years, from fall 1999 through fall 2001, and randomly assigned within schools to either the program or the control group. The results in this report are based on a survey given to 2,057 youth in 2005 and 2006, roughly four to six years after they began participating in the study; 1,209 had participated in one of the Title V, Section 510 abstinence education programs and 848 had been assigned to the control group. By the time the last follow-up survey was completed, youth had entered their mid to late teens, permitting the researchers to reliably measure program impacts on teen sexual activity and other risk behaviors.

School bullying affects majority of elementary students

Thu, 12 Apr 2007 01:59:57 PST

( from http://www.rxpgnews.com ) Nine out of 10 elementary students have been bullied by their peers, according to a simple questionnaire developed by researchers at Lucile Packard Children's Hospital and the Stanford University School of Medicine. What's more, nearly six in 10 children surveyed in the preliminary study reported participating in some type of bullying themselves in the past year.

The survey explored two forms of bullying: direct, such as threatening physical harm, and indirect, such as excluding someone or spreading rumors. The researchers say the five-minute questionnaire is the first simple, reliable way for teachers and physicians to identify kids at risk and to measure the success of interventions aimed at reducing bullying in schools.

"We know that both bullies and victims tend to suffer higher levels of depression and other mental health problems throughout their lives," said child psychiatrist Tom Tarshis, MD, lead author of the study. "We need to change the perception that bullying at school is a part of life and that victims just need to toughen up."

Tarshis was completing a fellowship in child psychiatry and research at Packard Children's at the time he developed the questionnaire. He is currently the director of the Bay Area Children's Association. The research will be published in the April issue of the Journal of Developmental and Behavioral Pediatrics.

"When I first started to study this subject, there was no real questionnaire that had been tested," said Tarshis. "We couldn't take the next step until we had a tool that we knew worked."

Although the classic definition of bullying brings to mind fistfights in the schoolyard, other more subtle forms of torment also were surveyed. Tarshis recounted a girl in the ninth grade whose friends decided to stop speaking to her, spread nasty rumors about her and exclude her from activities, all right under the nose of an unsuspecting teacher.

"It was a little distressing how prevalent the problem is even in the middle- to upper-middle-class schools we surveyed," said Tarshis.

He and his co-author, Lynne Huffman, MD, associate professor of pediatrics and of psychiatry at the School of Medicine, surveyed 270 children in grades three through six in two schools in California and one in Arizona to determine if the 22-item questionnaire yielded statistically accurate results. Students were scored based on their responses - never, sometimes or often - to such statements as, "At recess I play by myself," "Other students ignore me on purpose," and "Other students leave me out of games on purpose."

Tarshis and Huffman then compared the results to those of other, more complicated surveys intended to identify bullies and victims. They also administered their survey twice to 175 of the students to determine if the results were consistent over time. They found that the responses were highly reliable, and the survey was easily understood and completed by even the youngest students in the sample.

"We found it particularly interesting that these indications of victimization and bullying are apparent at very young ages," said Huffman. "Our hope is that this questionnaire will be utilized by teachers, pediatricians and even child psychiatrists to identify those children needing early and direct intervention."

The stakes are high. Previous research has shown that, without intervention, bullying behavior persists over time: a child who is a bully in kindergarten is often a bully in elementary school, high school and beyond. Such behaviors are not without consequence, though. These career bullies are not only slightly more likely than their peers to serve prison time as adults, they also tend to suffer from depression.

Perhaps not surprisingly, kids who are routinely victimized exhibit higher levels of depression, anxiety and suicidal thoughts than do non-victims. Such statistics highlight the importance of being able to identify at-risk kids and assess the effectiveness of interventions.

Efforts to stop school bullying have been gathering steam for several years. Those most likely to be effective, according to Tarshis, promote an attitude change from the principal to the recess monitors to the parents. They range from presentations to entire schools to discussions with individual students about how to respond when they are bullied or when they see someone bullying another student.

"Positive peer pressure is an important component of effective intervention," said Tarshis. "When uninvolved students step up and let the perpetrator know that their behavior is not acceptable, it's a powerful message."

Virtual racing seems to lead to aggressive driving

Tue, 27 Mar 2007 08:18:26 PST

( from http://www.rxpgnews.com ) Psychologists have taken the âmedia primingâ effects of popular video console and PC-based games on the road, finding that virtual racing seems to lead to aggressive driving and a propensity for risk taking. Extending prior findings on how aggressive virtual-shooter games increase aggression-related thoughts, feelings and behaviors, researchers at Munich's Ludwig-Maximilians University and the Allianz Center for Technology found that of 198 men and women, those who play more virtual car-racing games were more likely to report that they drive aggressively and get in accidents. Less frequent virtual racing was associated with more cautious driving.

The findings appear in the March issue of the Journal of Experimental Psychology: Applied, which is published by the American Psychological Association.

Linking media priming effects â the way virtual aggression can lead to the real thing -- to behavior, a second study found that men who played even one virtual racing game subsequently took significantly higher risks in critical traffic situations on a computer simulator than did men who played a neutral game. Sixty-eight men were in this study.

Finally, the researchers assigned 83 men to play either typical racing or neutral games on a Sony Playstation. In the racing games, say the authors, âTo win, participants had to massively violate traffic rules (e.g., drive on the sidewalk, crash into other cards, drive at high speed).â Those who raced subsequently reported a significantly higher accessibility of thoughts and feelings linked to risk-taking than did those who played a neutral game.

Together, the findings suggest that playing racing games leads to riskier driving. The studies also highlight mediating factors, such as how the racing games prompt greater risk-taking thoughts and feelings, which may then result in higher-risk behavior.

The studies make both theoretical and practical contributions. First, the results support social-cognitive explanations of media priming effects, in which people built up mental models â in this case, of aggressive thoughts and feelings â easily triggered by a learned stimulus. That inner aggression is then the starting point for aggressive behaviors. The authors also showed that âpositively framedâ (the games are depicted as exciting and fun; they're also very popular) risky media content activates thoughts and feelings of arousal and excitement that are linked to increased risk taking.

Second, the authors observe that on a practical level, âOur results pose the question whether playing racing games leads to accidents in real-life road traffic.â Based on their findings and prior research, they assert that, âPlaying racing games could provoke unsafe driving. â¦ Practitioners in the field of road traffic safety should bear in mind the possibility that racing games indeed make road traffic less safe, not least because game players are mostly young adults, acknowledged as the highest accident-race group.â

Given that children start playing these games on average at age 10 (based on previous research by co-author JÃ¶rg Kubitzki), the researchers are concerned that racing games may instill risk-taking attitudes that lead to unsafe driving when children grow up and get behind the wheel.

Emotional responses usually take over rational responses in decision making

Fri, 16 Feb 2007 08:26:52 PST

( from http://www.rxpgnews.com ) The human brain is set up to simultaneously process two kinds of information: the emotional and the empirical. But in most people, emotional responses are much stronger than the rational response and usually take over, according to Michigan State University environmental science and policy researcher Joseph Arvai.

"People tend to have a hard time evaluating numbers, even when the numbers are clear and right in front of them," Arvai said. "In contrast, the emotional responses that are conjured up by problems like terrorism and crime are so strong that most people don't factor in the empirical evidence when making decisions."

In his research, Arvai and graduate student Robyn Wilson, of Ohio State University, asked individuals to consider two risk scenarios common in many state parks. One involved crime - "vandalism and purse snatching" and the other involved damage to property from white-tailed deer, such as auto-deer collisions. The participants were asked to indicate which problem required more attention from risk managers.

"The neat thing with crime and deer overpopulation is that both risks could be measured on the same scale, which made our jobs as researchers easier," Arvai explained. "But because crime incites such a negative emotional response from most people, it consistently received more attention, even when the numbers showed that the risks from deer were much worse. We had to ratchet up the deer damage until it was ridiculously high before people noticed that it was a higher risk than crime.

"The bigger problem we've uncovered is that this response isn't limited to crime and deer," he continued. "We see it happening in other areas: terrorism, the war in Iraq and infectious diseases."

Cell phone tunes could reflect one's personality

Sun, 10 Dec 2006 14:17:59 PST

( from http://www.rxpgnews.com ) New Delhi, Dec 10 - Hello tunes - the myriad melodies you hear when you call someone on the mobile phone - could reflect the user's personality and also affect the mood of the listener, say psychologists.

'Bright and light tones may reflect a bright personality but it could also be associated with someone who is feeling low and wants to feel bright,' leading psychiatrist Sanjay Chugh told IANS.

'Sad tones suggest an underlying depression or low mood. Romantic tones have their own story to tell,' adds Chugh, who is the founder chairman of the International Institute of Mental Health here.

But a hello tune could also prove to be a complete contrast to the user's personality.

'When we choose something, our conscious and sub-conscious minds are involved. And unknowingly, our choice reflects our personality. In an effort to be what you feel like, the choice of the hello tune can depict the core of a person. But sometimes it can be completely contradictory to that as well,' says S.K. Sharma, another Delhi-based psychologist.

Hello tunes have now become an alternative for those who are shy to speak up or send a message. According to Chugh, the content and tone of the hello tune 'directly affects the mood of the listener'.

Says Amit Soni, a student: 'I set my hello tune according to my mental state. It has a direct effect on the caller. If I'm in love, I will set a romantic hello tune because I want my love interest to listen what I'm feeling. If I've just broken off, I'll put a sad song like 'Tadap Tadap Ke...'.'

But some believe that the user's surroundings and current trends also contribute to the selection of hello tunes.

'The hello tune also depends on the nature and surroundings of an individual. If someone is religious by nature, he will put a spiritual tune. And college-going people will prefer a trendy tune,' remarks Ajeet Singh, a media professional.

The surge in demand for hello tunes can also be attributed to the successful strategies of telecom companies.

'We launched this service in September 2004 and till April 2006, there have been 75 million downloads of all music forms - hello tunes, ring tones and music tracks,' says an informed source in Airtel, a leading telecom service provider in India.

'We have a database of 25,000 songs in 20 different languages, which we keep updating,' the source adds.

But the love for cinema and film songs is also a known driving force among the youngsters.

'There is a huge demand for Hindi and English songs but there is also considerable demand for regional music. Every time a new Bollywood flick releases, the demand for its songs as Hello tunes goes up,' the source says.

But Chugh notes that telecom service providers 'often thrust these tunes down the user's throat' but added that people could turn to these tunes in an 'effort to keep up with the vogue.'

Touch tracking bypasses mind control

Tue, 21 Nov 2006 10:32:13 PST

( from http://www.rxpgnews.com ) For people unable to simultaneously rub their stomach while patting their head, a new twist may be at hand. Touch, rather than concentration, could let people multi-task with their hands, and this may also potentially help improve the performance of people with coordination problems, according to psychologists.

"Most normal people cannot simultaneously draw a circle with one hand and a square with the other," says David Rosenbaum, distinguished professor of psychology and director of Penn State's Laboratory For Cognition and Action. "It is a fundamental limitation that the nervous system seems to impose on the hands for reasons that are not fully understood."

Rosenbaum thinks the key to the problem lies in the higher neural centers responsible for concentration on multiple tasks. "When you perform one task, you conceptualize it as one," he explains, "but when you have two tasks to do at the same time that you can't think of as one, it gets complicated because the mind has to shift attention back and forth from one task to the other."

To test this idea, Rosenbaum and his Penn State colleagues, Amanda Dawson, a recent Ph.D. recipient, and John Challis, associate professor of kinesiology, set up an experiment in which participants could track moving objects with light touch and without having to concentrate on the tracking.

Volunteer participants who kept their eyes closed during the experiment tried to keep their hands in contact with two moving disks. The participants could independently trace the paths of the disks, even when the disks moved in ways that are normally very hard for people to produce on their own. For example, they could trace a square and a circle at the same time, which is normally impossible.

The disks were driven by moving magnets on the other size of an opaque pane of glass. "If the person exerted little more than a feather touch on the disks, the magnets decoupled and the experiment came to a stop. So the participants' hands were not simply being dragged along by the magnetic force on the disks," explains Rosenbaum, whose findings appear in the November/December issue of the Journal of Experimental Psychology.

Researchers say the test provides the strongest evidence yet that the reason most persons are unable to voluntarily multi-task with their two hands is that their mind gets in the way.

"We created a situation where each hand simply reacts to the motion of the object being felt, so in effect we bypassed the high-level cognitive system. The excellent performance displayed by our participants took no training whatsoever," added Rosenbaum. "Using haptics, we managed to get into the motor system through the backdoor."

Researchers say the findings could benefit people with coordination problems, and that haptic tracking might help such persons learn to better control their irregular hand movements.

Making the connection between a sound and a reward changes behavioral response

Fri, 20 Oct 2006 23:34:00 PST

( from http://www.rxpgnews.com ) If youve ever wondered how you recognize your mothers voice without seeing her face or how you discern your cell phones ring in a crowded room, researchers may have another piece of the answer.

Their work indicates that once you figure out your mothers voice is a good thing most days - fairly significant changes occur in the sensory cortex, the part of the brain that responds to sound.

When something starts to predict a good outcome is going to happen, the sensory part of the brain that responds to those events starts to respond more strongly, making it easier for the brain to cause a behavioral response, says Dr. David T. Blake, neuroscientist at the Medical College of Georgia and lead author on a study in the Oct. 19 issue of Neuron.

By monitoring the action potentials of about a dozen key neurons in monkey test subjects, researchers found neuronal responsiveness increases dramatically after just a few training sessions.

These neuronal fireworks were short-lived, replaced by a rewiring of the brain that shows the animal has learned, Dr. Blake says.

In the few monkeys that initially didnt make the connection that a change in pitch in a series of sounds meant they were getting a juice reward, no brain changes occurred.

The same processes happen to people as we learn, especially in the area of sensory discrimination, Dr. Blake says. We learn how to tell peoples faces apart, we learn how to distinguish different words whether they are delivered orally or written. We can identify different speakers by the tenor and tone of their voice. All of these abilities are part of sensory discrimination, so we are studying how the brain changes as part of sensory discrimination learning.

The findings have wide implications for learning, including improving treatment for children with language learning impairments, such as dyslexia, and increasing literacy, Dr. Blake says. California-based Scientific Learning, a neuroscience company that grew out of the University of California, San Francisco, already is using advances in understanding behavioral learning to develop computer programs that dramatically improve the reading skills of dyslexic children. Another San Francisco-based neuroscience company, Posit Science, is exploring its potential in age-related cognitive decline, he says.

People have studied since the time of Pavlov how associating sensory stimuli with reward causes behavioral change, Dr. Blake says. What we have done is identify how that change occurs and over what time course it occurs in one part of these multiple brain systems that are linked together so that Pavlovs dog can start salivating after the bell rings.

More than 100 years ago, while studying the gastric system of dogs, the Russian physiologist found what he called a conditioned reflex: that after a period of ringing a metronome during feeding that the dogs began salivating just hearing the metronomes beat.

Dr. Blake is studying the neuronal responses of more humanlike monkeys with the idea of better understanding why.

Researchers were able to monitor neuronal response using technology Dr. Blake helped develop that is similar to deep brain stimulation used in patients but with much smaller electrodes.

In work published in 2002 in the Proceedings of the National Academy of Sciences, Dr. Blake first taught monkeys that when they leaned forward to break an infrared beam, a series of sounds would start. If they leaned back after a change in the sound series, they got an appetitive reward, he says. When they do this, the response of their neurons to those sounds doubles and triples in the first two days after they learn that very simple behavior. They learn that moving their head at that time will lead to reward.

The new study indicates that the monkeys just have to make the connection between the sound change and juice reward for brain changes to occur and that at least some of them dont have to move a muscle to make that happen.

This work suggests the learning does not have to be active for some animals, that they dont all have to cause the reward to make the brain changes, says Dr. Blake. They just have to learn that the stimulus predicts the reward.

Its an important computational point because there is a lot of interest right now in the brains ability to backtrack in time from rewards to find out the earliest thing that predicts that reward. When the monkey identifies the sound change as the cue its supposed to respond to get rewarded, learning and brain changes happen.

Irrational decisions driven by emotions

Fri, 04 Aug 2006 20:16:00 PST

( from http://www.rxpgnews.com ) Irrational behaviour arises as a consequence of emotional reactions evoked when faced with difficult decisions, according to new research at UCL (University College London), funded by the Wellcome Trust. The UCL study suggests that rational behaviour may stem from an ability to override automatic emotional responses, rather than an absence of emotion per se.

It has long been assumed in classical theories of economics that people act entirely rationally when taking decisions. However, it has increasingly become recognized that humans often act irrationally, as a consequence of biasing influences. For example, people are strongly and consistently affected by the way in which a question is presented. An operation that has 40 per cent probability of success seems more appealing than one that has a 60 per cent chance of failure.

In the study, published in the journal Science, UCL researchers used a gambling experiment to establish the cognitive basis for rational decision-making. The goal of the task was to accumulate as much money as possible, with the incentive of being paid in real money in proportion to the money won during the experiment. Participants were given a starting amount of money (£50) at the beginning of each trial. They were then asked to choose between either a sure option or a gamble option (where they would have a certain chance of winning the entire amount, but also of losing it all). Subjects were presented with these choices under two different frames (i.e. scenarios), in which the sure option was worded either as the amount to be kept from the starting amount ("keep £20"), or the amount to be deducted ("lose £30"). The two options, although worded differently, would result in exactly the same outcome, i.e. that the participant would be left with £20.

The UCL study found that participants were more likely to gamble at the threat of losing £30 than the offer of keeping £20. On average, when presented with the "keep" option, participants chose to gamble 43 per cent of the time compared with 62 per cent for the "lose" option. Furthermore, there was a marked difference in behaviour between participants. Some people adopted a more rational approach and gambled more equally and consistently under both frames, while others showed a real aversion to risk in the "keep" frame while at the same time displaying high risk-seeking behaviour in the "lose" frame.

Brain imaging revealed that the amygdala, a region thought to control our emotions and mediate the 'fight or flight' reaction, underpinned this bias in the decision process. Moreover, the UCL study revealed that people with more rational behaviour had greater brain activity in the prefrontal cortex, a region known to be involved in higher-order executive processes, suggesting that their brains are better able to incorporate their emotions into a more balanced reasoning process.

Mr Benedetto de Martino, of the UCL Institute of Neurology, says: "It is well known that human choices are affected by the way in which a question is phrased. For example, saying an operation carries an 80 per cent survival rate may trigger a different response compared to saying that an operation has a 20 per cent chance of dying from it, even though they offer exactly the same degree of risk.

"Our study provides neurobiological evidence that an amygdala-based emotional system underpins this biasing of human decisions. Moreover, we found that people are rational, or irrational, to widely differing amounts. Interestingly, the amygdala was active across all participants, regardless of whether they behaved rationally or irrationally, suggesting that everyone experiences an emotional reaction when faced with such choices. However, we found that more rational individuals had greater activation in their orbitofrontal cortex (a region of prefrontal cortex) suggesting that rational individuals are able to better manage or perhaps override their emotional responses."

Mice learn set shifting tasks to help treat human psychiatric disorders

Wed, 02 Aug 2006 11:48:00 PST

( from http://www.rxpgnews.com ) Mice that couldn't be dissuaded from the object of their attention by a piece of sweet, crunchy cereal may help researchers find new treatments and cures for human disorders like autism and Parkinson's disease.

For the first time, a psychiatric test for monitoring many human mental abnormalities has been adapted for use in mice, according to researchers at Purdue University, University of California-Davis and Justus-Liebig University in Giessen, Germany. The test involves the ability to switch attention from one task to another, a skill often impaired in people with autism and similar illnesses.

"Without a measure of cognitive deficit in mice that is relevant to such disorders in humans, research into new diagnostic methods, treatments and cures is severely hindered," said Joseph Garner, a Purdue assistant professor of animal sciences and the study's lead author. "The level of complexity at which we assess mouse behavior is often very rudimentary, and it just does not match up with subtleties of the cognitive deficits in human mental dysfunction or with the tools we use to study the mechanisms that underlie disorders in people."

Garner and his colleagues designed a task to measure a process called set shifting in which a focus on one object must be abandoned in favor of another object or task. This test long has been used to monitor brain processes involved in human psychiatric disorders and also has been tailored to a few other animals. However, researchers previously had not adapted it to the most-used of research mammals, the common laboratory mouse.

"Set shifting underlies our ability to use categories in day-to-day life and our ability to do many things including execute complex plans," Garner said.

Garner's team reports its findings in the journal Behavioural Brain Research, which is currently online.

Set shifting as an important neuropsychological skill applies to more human mental disorders than any other measure, Garner said. Mechanisms in the brain that enable people to shift their focus from one task to another also seem to be present in most other mammals and probably also in birds.

"Set shifting occurs when youve learned to pay attention to one thing and then need to concentrate on something different," he said. "For instance, I could ask you to name the suit on playing cards as I turn them over, and then I'd ask you to tell me the numbers on the next cards I turn over.

"But you might fail to tell me the numbers because you are continuing to pay attention to the previous set the card suits. Youve both learned to pay attention to the suits and that the numbers are irrelevant so you should ignore them."

Mice compose the majority of medical research animals, but since no test existed to monitor them for such skills as set shifting, their usefulness in studying autism, other similar diseases and traumatic brain injuries was limited, Garner said.

The Garner team's mice were tested in a maze with rewards of one-quarter of a piece of sweetened cereal hidden in two-inch diameter metal bowls. The scientists varied the material inside the bowls where the cereal piece was hidden and also varied the outer texture and smell of the bowls.

The rodents learned to find the cereal by using a cue such as the bowl's outer texture. After experience solving a number of tasks with this cue, the animals were given a new cue for finding the cereal, such as the bowl's smell.

"Like people performing a series of similar tasks over and over and then having to change their focus to a new problem, the mice continued to look for the bowl with the same outer texture to find the cereal," Garner said. "The more times they had used the bowl texture as a cue, the more difficult it was for the animals to change to the new food-finding cue."

Almost all people have a little difficulty set-shifting in a task like this, he said. However certain patient groups find it very difficult. Therefore, similar tests are used to measure brain function in people.

"The data collected in this study begin to solve the problem of not having a way of measuring these neurological mechanisms in mice," Garner said. "Previously we were not able to measure this fundamental disease process in autism, trichotillomania (hair pulling), obsessive-compulsive disorder, Parkinson's disease, schizophrenia, Tourette's syndrome, traumatic frontal brain lobe injury and a host of other human mental disorders for which set shifting is an important monitoring tool."

According to the Centers for Disease Control and Prevention (CDC), 3.4 per 1,000 children have autism or another autism spectrum disorder, making these disorders about as common as Type I juvenile diabetes. This rate is higher than for other childhood disabilities, including Down's syndrome, cancer, cerebral palsy, hearing loss and vision impairment.

Although the number of children diagnosed with autism has increased dramatically over the past 12 years, the upward spiral may be due to better, more widespread understanding and diagnosis of the mental impairment, CDC experts said. Trichotillomania, which affects 3.4 percent of women, and some other disorders are even more prevalent.

How behaviors can be changed or created

Sun, 30 Jul 2006 03:06:00 PST

( from http://www.rxpgnews.com ) UC Riverside researchers have made a major leap forward in understanding how the brain programs innate behavior. The discovery could have future applications in engineering new behaviors in animals and intelligent robots.

Innate or "instinctive" behaviors are inborn and do not require learning or prior experience to be performed. Examples include courtship and sexual behaviors, escape and defensive maneuvers, and aggression.

Using the common fruit fly as a model organism, the researchers found through laboratory experiments that the innate behavior is initiated by a "command" hormone that orchestrates activities in discrete groups of peptide neurons in the brain. Peptide neurons are brain cells that release small proteins to communicate with other brain cells and the body.

The researchers report that the command hormone, called ecdysis-triggering hormone or ETH, activates discrete groups of brain peptide neurons in a stepwise manner, making the fruit fly perform a well-defined sequence of behaviors. The researchers propose that similar mechanisms could account for innate behaviors in other animals and even humans.

Study results appear as the cover article in this week's issue of Current Biology.

"To our knowledge, we are the first to describe how a circulating hormone turns on sequential steps of an innate behavior by inducing programmed release of brain chemicals," said Young-Joon Kim, a postgraduate researcher in UCR's Department of Entomology working with Michael Adams, professor of cell biology and neuroscience and professor of entomology, and the first author of the paper. "It is well known that such behaviors for example, sexual behavior or those related to aggression, escape or defense are programmed in the brain, and all are laid down in the genome. We found that not only do steps involved in innate behavior match exactly with discrete activities of the neurons in the brain but also that specific groups of peptide neurons are activated at very precise times, leading to each successive step of the behavioral sequence."

In their experiments, which involved state of the art imaging techniques that helped the researchers see activated neurons light up in the fruit fly brain, the researchers specifically focused on arthropods, such as insects. Insects pass through multiple developmental stages during their life history. Each transition requires molting, a process in which a new exoskeleton (or cuticle) is produced and the old is shed. Insects shed the old cuticle by performing an innate behavior consisting of three distinct steps lasting about 100 minutes in total.

First, the researchers described the ecdysis sequence, an innate behavior that insects perform to escape their old cuticle, and showed that the insect initiates behavior shortly after appearance of ETH in the blood. The researchers then demonstrated that injection of the hormone into an animal generates the same behavior. To investigate mechanisms underlying this hormone-induced behavior, they used real-time imaging techniques to reveal activities in discrete sets of peptide neurons at very precise times, which corresponded to each successive step of the behavioral sequence. The researchers confirmed the results by showing that behavioral steps disappear or are altered upon killing certain groups of brain neurons with genetic tools.

"Our results apply not only to insects; they also may provide insights into how, in general, the mammalian brain programs behavior, and how it and the body schedule events," said Adams, who led the research team. "By understanding how innate behavior is wired in the brain, it becomes possible to manipulate behavior change its order, delay it or even eliminate it altogether all of which opens up ethical questions as to whether scientists should, or would want to, engineer behavior in this way in the future."

The fruit fly is a powerful tool and a classic laboratory model for understanding human diseases and genetics because it shares many genes and biochemical pathways with humans.

People more likely to help others they think are 'like them'

Mon, 10 Jul 2006 07:48:00 PST

( from http://www.rxpgnews.com ) Feelings of empathy lead to actions of helping but only between members of the same group according to a recent study. The research, led by Stefan Stürmer of the University of Kiel, is presented in the article "Empathy-Motivated Helping: The Moderating Role of Group Membership." The article discusses two different studies, one using a real-world, intercultural scenario and the other using a mixture of people with no obvious differences besides gender. Researchers concluded that, while all the people felt empathy for someone in distress, they only tended to assist if the needy person was viewed as a member of their own "in-group."

The first study, using a real-world intercultural scenario, split German and Muslim male participants into culturally-defined groups. When everyone learned that another participant was having difficulty finding housing, they all felt empathy for the other regardless of what group they were in. However, when asked about their intentions to help the participant, empathy had a stronger impact when the other was categorized as a member of their in-group.

To further substantiate the findings from the first study, the second study created "minimal" in-groups and out-groups using a mixture of male and female participants without obvious cultural differences. As in the first study, when participants learned that another participant needed financial help due to the loss of money and a credit card, they all felt empathy, but actual assistance was provided only when the distressed person was a member of their in-group.

Avoiding Punishment Is Its Own Reward

Wed, 05 Jul 2006 14:50:00 PST

( from http://www.rxpgnews.com ) For my now-departed, wonderful old cat named Bear, life didn't get any better than raw shrimp. Seeing the little white package emerge from the fridge always caught his attention, but what set him into high-shriek mode was the sound of shrimp being peeled under running waterhe knew culinary bliss was at hand. Bear's behavior was perfectly in keeping with the theory of reinforcement learning: through instrumental conditioning, animals learn to choose responses associated with producing favorable outcomes and avoiding unpleasant onestypically by learning to associate two normally unrelated stimuli. The shrimp reward reinforced associations between stimulus (the sound of peeling and washing, rather than the sight of shrimp) and response (expectant wailing).

The flipside of reward learning, avoidance learning, doesn't fit so neatly into the framework of reinforcement theories. Reinforcement theory predicts that behavior should rapidly disappear in the absence of explicit reinforcement. But studies show that once an animal manages to avoid punishmentfor example, when a monkey learns to avoid a bitter drink by pressing a particular buttonit may continue to perform the avoidance response even when it never experiences negative feedback again.

This apparent disconnect between avoidance learning and reinforcement theory could be resolved if avoiding punishment is itself a reward, a hypothesis that intrigued Hackjin Kim, Shinsuke Shimojo, and John O'Doherty. This possibility has been proposed before, but never tested. In a new study, Kim et al. investigated this question by scanning the brains of humans performing a simple instrumental conditioning task. A brain area called the medial orbitofrontal cortex (OFC) has been linked to reward-related stimuli, particularly when the reward involves money. The researchers reasoned that if avoidance learning and reward were equivalent, then the OFC should be activated in both contexts. If they are distinct cognitive processes, then each process should activate different regions.

Sixteen people participated in the study, during which they could either lose or win one dollar in an instrumental choice task. During the experimental trials, participants selected one of two fractal images presented on a screen. After a fractal was chosen, it became brighter, and four seconds later the participant got one of four types of feedback: reward (a picture of a dollar bill and the message, You win $1!), negative outcome (same image, with the text, You lost $1!), neutral (a scrambled bill with the text, No change), or nothing (a blank screen). During reward trials, the choice led to a high or low probability of reward (earning a dollar); during avoidance trials, the choice led to a high or low probability of avoiding a negative outcome (losing a dollar).

Over time, participants learned to choose fractals associated with a greater probability of reward and a lower probability of a negative outcome. And, as predicted, the medial OFC showed a higher response when participants chose an option that resulted in not losing the dollar or in winning it. Conversely, when participants' choices resulted in negative outcomesand when there was no reward offeredOFC activity declined. Compared to neutral trials, reward and avoidance events produced significantly greater brain activity, while negative outcomes and neutral events linked to no chance of reward resulted in significantly decreased activity. Kim et al. argue that these functional magnetic resonance imaging (fMRI) results provide direct evidence that avoiding bad outcomes and receiving a reward provoke a similar response in the medial OFC.

The expectation of reward also produced heightened activity in the medial and lateral OFC. To analyze the learning response during reward and avoidance trials, the researchers input the results of the behavioral experiments into a computational reinforcement model. As participants received rewards over the course of learning, those choices resulting in reward increased in value; by contrast, the value of choices resulting in bad outcomes decreased. As links between actions and their outcomes become clearer, the wisdom or folly of a choice also becomes clearer.

Avoiding negative outcomes and receiving rewards amount to the same thing for the brain: achieving a goal. Reward serves as an external signal that reinforces behavior associated with a positive outcome, Kim et al. explain, and punishment amounts to an intrinsic reward signal that reinforces actions linked to avoiding bad outcomes. With fMRI evidence connecting avoidance and reward circuits, researchers can now determine which neuron populations within the OFC contribute to the avoidancereward responseand perhaps shed light on the neurobiological roots of pathological risk-seeking behavior.

Does psychological treatment for adult sex offenders work?

Sat, 01 Jul 2006 17:43:00 PST

( from http://www.rxpgnews.com ) Psychological treatment for adult sex offenders can reduce reoffending rates but does not provide a cure, say experts in an editorial in this week's BMJ.

Sexual offending is a public health issue and a social problem. Psychological treatment is widely used and is often mandated in the sentencing decision for sexual offenders. But just how effective are psychological treatment programmes? Are they too readily accepted uncritically?

Specialists in psychology and criminology review the evidence from published studies.

In an analysis of randomised controlled trials on behavioural treatments, they found that most studies were too small to be informative, although statistically significant improvements were recorded across some groups of offenders.

The largest, longest trial compared group therapy with no group therapy for 231 men guilty of child abuse, exhibitionism, or sexual assault. During the subsequent 10 years, a greater proportion of those allocated to group therapy were re-arrested, but this did not reach statistical significance.

However, evidence from these types of trials provides only a fraction of the knowledge needed, particularly on recidivism (used here to mean a repeat sexual offence), say the authors.

Treatment failure is associated with higher rates of recidivism, and offenders who successfully complete a treatment programme reoffend less often and less seriously (that is non-sexual reoffending) than those who do not show that they have understood and worked through the relevant psychological issues.

Paedophilia cannot always be successfully treated, they write. Better understanding of the outcomes of treatments either controlling and moderating or harming and worsening behaviour could at least focus on the most beneficial and cost effective interventions.

There is enormous political and institutional pressure to prove that treatment works. Assessment of all outcomes must take the expectations of researchers into account, and also offenders' and therapists' perceptions of treatment.

It should be possible to combine the strength of randomised controlled trials with the collection of good qualitative data and to ensure that psychological interventions for sexual offenders are assessed effectively, they conclude.

How people behave differently when they are being watched

Thu, 29 Jun 2006 04:39:00 PST

( from http://www.rxpgnews.com ) Scientists have found a way of making people behave more honestly in an experiment that could aid strategies for tackling anti-social behaviour.

A team from Newcastle University found people put nearly three times as much money into an 'honesty box' when they were being watched by a pair of eyes on a poster, compared with a poster that featured an image of flowers.

The researchers say the eye pictures were probably influential because the brain naturally reacts to images of faces and eyes. It seems people were subconsciously cooperating with the honesty box when it featured pictures of eyes rather than flowers.

They also say the findings show how people behave differently when they believe they are being watched because they are worried what others will think of them. Being seen to co-operate is a good long-term strategy for individuals because it is likely to mean others will return the gesture when needed.

Details of the experiment, believed to be the first to test how cues of being watched affect people's tendency for social co-operation in a real-life setting, are published today, Wednesday June 28, in the Royal Society journal Biology Letters.

An honesty box is a system of payment which relies on people's honesty to pay a specified price for goods or services - there is no cashier to check whether they are doing so.

For this experiment, lead researcher Dr Melissa Bateson and her colleagues Drs Daniel Nettle and Gilbert Roberts, of the Evolution and Behaviour Research Group in the School of Biology and Psychology at Newcastle University, made use of a long-running 'honesty box' arrangement.

This had been operating as a way of paying for hot drinks in a common room used by around 48 staff for many years, so users had no reason to suspect an experiment was taking place.

An A5 poster was placed above the honesty box, listing prices of tea, coffee and milk. The poster also featured an image banner across the top, and this alternated each week between different pictures of flowers and images of eyes.

The eye pictures varied in the sex and head orientation but were all chosen so that the eyes were looking directly at the observer.

Each week the research team recorded the total amount of money collected and the volume of milk consumed as this was considered to be the best index available of total drink consumption.

The team then calculated the ratio of money collected to the volume of milk consumed in each week. On average, people paid 2.76 as much for their drinks on the weeks when the poster featured pictures of eyes.

Lead author of the study, Melissa Bateson, a Royal Society research fellow based at Newcastle University, said: "Our brains are programmed to respond to eyes and faces whether we are consciously aware of it or not.

"I was really surprised by how big the effect was as we were expecting it to be quite subtle but the statistics show that the eyes had a strong effect on our tea and coffee drinkers."

The findings could have applications in initiatives to curb anti-social behaviour or in law enforcement - perhaps in areas such as payment for public transport, road safety or the general issue of behaviour in public places.

The group now hopes to expand the study to involve a larger sample population.

Dr Bateson said: "Our findings suggest that people are less likely to be selfish if they feel they are being watched, which has huge implications for real life.

"For example, this could be applied to warnings about speed cameras. A sign bearing an image of a camera would have to be actively processed by our brains, as it is an artificial stimulus. Our research and previous studies suggest drivers would react much more quickly and positively to natural stimuli such as eyes and faces."

Broca's area also organizes behavioral hierarchies

Thu, 15 Jun 2006 12:03:00 PST

( from http://www.rxpgnews.com ) Researchers have discovered that Broca's area in the brain--best known as the region that evolved to manage speech production--is a major "executive" center in the brain for organizing hierarchies of behaviors. Such planning ability, from cooking a meal to organizing a space mission, is considered one of the hallmarks of human intelligence.

The researchers found that Broca's area--which lies on the left side of the brain about in the temple region--and its counterpart on the right side activate when people are asked to organize plans of action. They said their finding of the general executive function of Broca's area could explain its key role in language production.

Importantly, the researchers found that this executive function of these cortical regions was distinct from the organization of temporal sequences of actions.

The researchers, Etienne Koechlin and Thomas Jubault of Université Pierre et Marie Curie and Ecole Normale Supérieure, described their experiments in the June 15, 2006, issue of Neuron.

In their experiments, the researchers asked volunteers to execute a sequence of button presses when they saw colored squares or letters on a screen. Koechlin and Jubault designed their experiment so that they could precisely distinguish hierarchical planning of tasks from the temporal organization of tasks. The subjects were asked to perform both simple sequences of button presses in response to a stimulus, "simple action chunks," and "superordinate action chunks." Simple action chucks were single motor acts that required sequential action. Superordinate action chunks included "a sequence of categorization tasks, like sorting a deck of playing cards first by color, then by suit, then by rank."

While they performed the tasks, the subjects were scanned using functional magnetic resonance imaging. This scanning technique involves using harmless magnetic fields and radio waves to measure blood flow in brain regions, which reflects brain activity.

Koechlin and Jubault found that Broca's area and its right-brain counterpart were clearly responsible for hierarchical processing.

"Our results provide evidence that Broca's area and its right homolog implement a specialized executive system controlling the selection and nesting of action segments comprising the hierarchical structure of behavioral plans, regardless of their temporal structure," wrote the researchers. "This finding suggests a basic segregation between prefrontal executive systems involved in the hierarchical and temporal organization of goal-directed behaviors, highlighting the specific contribution of Broca's area and its right homolog to executive control.

"Interestingly, Broca's area is mostly known to be critically involved in human language, especially in processing hierarchical structures of human language and in organizing linguistic segments that compose speech," they wrote. They concluded that "our results support the view that Broca's area implements an executive function specialized for processing hierarchical structures in multiple domains of human cognition. We speculate that the modular executive system of hierarchical control we describe possibly captures key functional components that may explain the critical contribution of Broca's area to human language."

Erotic images elicit strong response from brain

Thu, 15 Jun 2006 11:36:00 PST

( from http://www.rxpgnews.com ) Researchers at Washington University School of Medicine in St. Louis measured brainwave activity of 264 women as they viewed a series of 55 color slides that contained various scenes from water skiers to snarling dogs to partially-clad couples in sensual poses.

What they found may seem like a "no brainer." When study volunteers viewed erotic pictures, their brains produced electrical responses that were stronger than those elicited by other material that was viewed, no matter how pleasant or disturbing the other material may have been. This difference in brainwave response emerged very quickly, suggesting that different neural circuits may be involved in the processing of erotic images.

"That surprised us," says first author Andrey P. Anokhin, Ph.D., research assistant professor of psychiatry. "We believed both pleasant and disturbing images would evoke a rapid response, but erotic scenes always elicited the strongest response."

As subjects looked at the slides, electrodes on their scalps measured changes in the brain's electrical activity called event-related potentials (ERPs). The researchers learned that regardless of a picture's content, the brain acts very quickly to classify the visual image. The ERPs begin firing in the brain's cortex long before a person is conscious of whether they are seeing a picture that is pleasant, unpleasant or neutral.

But when the picture is erotic, ERPs begin firing within 160 milliseconds, about 20 percent faster than occurred with any of the other pictures. Soon after, the ERPs begin to diverge, with processing taking place in different brain structures for erotic pictures than those that process the other images.

"When we present a stimulus to a subject for example, when a picture appears on a screen it changes ongoing brain activity in certain ways, and we can detect those changes," Anokhin says.

Pictures appeared on a screen at 12 to 18 second intervals, and each picture remained on the screen for about 6 seconds. The subjects were instructed to do nothing other than look at the pictures.

A great deal of past research has suggested that men are more visual creatures than women and get more aroused by erotic images than women. Anokhin says the fact that the women's brains in this study exhibited such a quick response to erotic pictures suggests that, perhaps for evolutionary reasons, our brains are programmed to preferentially respond to erotic material.

"Usually men subjectively rate erotic material much higher than women," he says. "So based on those data we would expect lower responses in women, but that was not the case. Women have responses as strong as those seen in men."

Because the electroencephalogram (EEG) technology cannot pinpoint specific brain structures involved in this visual processing, Anokhin says it's not clear exactly which circuits are reacting to these visual scenes. Recent studies in primates recorded the electrical activity of single neural cells within the brain and have shown that the frontal cortex contains neurons that can discriminate between different categories of visual objects such as dogs versus cats. Whether or not the human prefrontal cortex contains special neurons that are "tuned" for sex remains a subject for future studies.

"The newer and more advanced technologies such as MRI and PET provide much better spatial resolution," he says. "Those methods can better localize areas of brain activity, but ERPs have a much better temporal resolution. The EEG can record neuronal activity in real time. When measuring activity in milliseconds, any delay is undesirable."

Most of Anokhin's research is centered on the genetic and neurobiological bases of behavioral traits that might be associated with increased vulnerability to alcoholism and addictive disorders. He believes this study could contribute to that work by detecting differences between responses to images with different emotional significance. Because many psychiatric disorders also are associated with poor processing of signals associated with reward and pleasure, as well as sexual disturbances, he believes the way the brain processes emotional pictures, including erotic materials, might help scientists better understand some forms of mental illness.

Men infer sexual interest before women do

Fri, 09 Jun 2006 13:53:00 PST

( from http://www.rxpgnews.com ) In the latest issue of Psychology of Women Quarterly, researchers find that men rate themselves and the women they just interacted with higher on sexual traits, such as flirtatiousness, than women rate men. The authors find that after a five-minute conversation with a stranger of the opposite gender, men were more likely to interpret ambiguous or friendly behavior as indicating sexual interest. "The findings suggest that men generally think in more sexual terms than women," the authors explain.

Within their brief conversation, partners introduced themselves and talked about college experiences. There was no significant difference in how men, compared to women, rated their conversation partners on agreeableness or extroversion. Nor was their evidence of sexual chemistry, as partners did not share a tendency to find each other attractive or desire a future interaction.

If women found their male partner as more partner physically attractive and saw him as more agreeable, they rated the partner higher on sexual traits. Men's ratings of women were also associated with physical attractiveness but unrelated to whether he saw her as agreeable or felt the conversation was enjoyable.

What do football and alcohol have to do with being a man?

Mon, 05 Jun 2006 17:01:00 PST

( from http://www.rxpgnews.com ) Men across the world will be getting the pints in and staring at the big screen this month as the World Cup kicks off in Germany. But what do football and alcohol have to do with being a man? A recent psychological study by the University of Sussex reveals that the roaring crowds may be drinking their way through the game in an effort to compensate for not being man enough to play in it.

The study, made up of in-depth interviews with thirty-one 18-21 year olds in inner London, investigates what young men consider to be masculine behaviour and how this affects their health. Dr Richard de Visser, lead researcher on the study Economic and Social Research Council (ESRC) sponsored study 'Young Men, Masculinity and Health' explains: "What is really interesting about the study, is the idea of using one type of typically masculine behaviour to compensate for another. For example, men who are not confident in their sporting abilities may try and make up for this by drinking excessively."

Because some men engage in unhealthy masculine behaviour, whilst others build their masculine identities through positive behaviour such as sport, the policy implications are huge. The project calls for greater understanding of attitudes to masculinity in health promotion.

"It seems that many young men aspire to an idea of masculinity that includes emotional and physical toughness, being the bread-winner, confidence in risk-taking and sexual confidence. A variety of behaviours, some that have a positive impact on health, some that have a negative, are employed to develop and demonstrate such masculine identities" says Dr de Visser.

Young men's health is currently an area of serious concern, with adolescent and young adult men being more likely to drink excessively and use illegal drugs, to engage in risky casual sex and to be to be killed or injured in road traffic accidents. This research shows that understanding the desire to appear masculine may hold the potential to reduce such unhealthy behaviour

"If these findings are used effectively," says Dr de Visser, "they may be able to have an impact on the growing levels of anti-social behaviour such as binge-drinking, violence and illicit drug-use. Young men could be encouraged to develop a competence in a healthy typically male area such as football to resist social pressures to engage in unhealthy masculine behaviours."

Prosopagnosia may affect 2 percent of population

Thu, 01 Jun 2006 12:47:00 PST

( from http://www.rxpgnews.com ) Researchers at Harvard University and University College London have developed diagnostic tests for prosopagnosia, a socially disabling inability to recognize or distinguish faces. They've already used the new test and a related web site (www.faceblind.org) to identify hundreds of "face-blind" individuals, far more than scientists had identified previously.

The researchers, led by Ken Nakayama and Richard Russell at Harvard and Bradley Duchaine at University College London, have found evidence that prosopagnosia, once thought to be exceedingly rare, may affect up to 2 percent of the population -- suggesting that millions of people may be face-blind.

"Until a few years ago, only 100 cases of prosopagnosia had been documented worldwide, but it now appears the condition is much less rare than had previously been assumed," says Nakayama, the Edgar Pierce Professor of Psychology in Harvard's Faculty of Arts and Sciences. "Testing of 1,600 individuals found that 2 percent of the general public may have face-blindness and a German group has recently made a similar estimate. It's conceivable that millions of people may have symptoms consistent with prosopagnosia, without even realizing it."

Tests developed by Nakayama and colleagues display dozens of images of cars, tools, guns, houses, and landscapes, along with close-cropped black-and-white pictures of faces. Some of the images recur during the cycle; subjects are asked to indicate, as quickly as possible, whether each image they see is new or repeated. Prosopagnosics who take these tests fail to recognize repetition among the faces in the series, even as they readily identify repeated pictures of other objects.

Reports of prosopagnosia date back to antiquity, although it wasn't until 1947 that researchers made the first modern, extensive description of symptoms. The neurological basis of the disorder remains poorly understood, although research has confirmed that the brain processes faces differently than other kinds of objects.

The condition can be embarrassing and lead to social isolation: Severe prosopagnosics may mistake complete strangers for acquaintances even as they fail to recognize family members, close friends, spouses, and even themselves. Many report difficulty watching television shows and movies, since they cannot keep track of characters. Face-blind individuals often compensate for their prosopagnosia using non-facial traits, such as hair, gait, clothing, voice, and context.

There are two broad categories of prosopagnosia. Most documented cases have been of acquired prosopagnosia, due to brain damage suffered after maturity from head trauma, stroke, and degenerative diseases. The other type is called developmental prosopagnosia. These individuals can have similar symptoms but with no evidence of brain damage. It is this group that may be the most common.

"Individuals who've been face-blind since childhood often do not realize that they are unable to recognize faces as well as others; they have never recognized faces normally so their impairment is not apparent to them," says Russell, a postdoctoral researcher in Harvard's Department of Psychology. "As a result, many individuals do not recognize their prosopagnosia until adolescence or adulthood."

Nerve cells in brain decide between apples and oranges

Thu, 11 May 2006 13:37:00 PST

( from http://www.rxpgnews.com ) When you are in the supermarket pondering over whether to buy apples or oranges a special group of nerve cells in the brain is at work categorising the fruit according to their value, a study conducted at the Harvard Medical School in Boston showed.

A team led by the medical school's Camillo Padoa-Schioppa identified the nerve cells after conducting experiments with monkeys. They were given two fruit juices of different quantities, Nature magazine reported.

The monkeys were initially given the choice of choosing between one drop of grape juice and one drop of apple juice - an easy decision because monkeys prefer grape.

In the second experiment, two drops of apple juice and one drop of grape juice were available with the monkeys again choosing their favourite.

The monkeys began to waver only when they were given the choice between three drops of apple juice and one drop of grape juice.

With the choice of between four drops of apple juice and one drop of grape juice the monkey always chose the less favourable bigger portion.

The researchers therefore found that the monkeys gave three drops of apple juice the same value as one drop of grape juice.

According to the researchers, certain nerve cells situated in the orbitofrontal cortex showed a higher reaction activity when the monkey was confronted with an object of high value such as three drops of grape juice.

Other research has found that damage to the orbitofrontal cortex, part of the limbic system and situated behind the eye orbits, was related to eating disorders and addictions such as gambling and drug abuse.

How Visual Stimulation Turns Up Bdnf Genes to Shape the Brain

Sun, 07 May 2006 15:37:00 PST

( from http://www.rxpgnews.com ) Scientists have long known that brains need neural activity to mature and that sensory input is most important during a specific window of time called the "critical period" when the brain is primed for aggressive learning. Vision, hearing and touch all develop during such critical periods, while other senses, such as the olfactory system, maintain lifelong plasticity.

The visual system provides an exemplary model for studying developmental plasticity, however, because of the pioneering work of Nobel prize-winning HMS researchers David Hubel and Torsten Wiesel describing the visual system's structure, prerequisite knowledge for investigating its flexibility. Although visual plasticity has been studied for over 40 years, exactly how sensory experience interacts with the built-in machinery that permits the brain to change its circuits is only beginning to be understood.

A new study focusing on the molecular roots of plasticity has found that visual stimulus turns up the expression of some genes and turns down the expression of others, somewhat like a conductor cueing the members of an orchestra. The study also found that during different stages of life in rodents, distinct sets of genes spring into action in response to visual input. These gene sets may work in concert to allow synapses and neural circuits to respond to visual activity and shape the brain, reports the May issue of Nature Neuroscience.

The investigators' identification of many distinct sets of activity-dependent genes follows a shift in neuroscience research toward a more holistic view of the role of genes in neural development and plasticity.

"What we found opens science up to a more global look at genes, from studying one gene at a time to looking at families of genes acting together," said first author Marta Majdan, Harvard Medical School research fellow in neurobiology. These findings suggest that genetic therapies for neurodegenerative diseases, some of which are largely limited to treatment focused on a single gene, will require more extensive knowledge of molecular pathways and gene interactions to be successful.

Majdan and co-author Carla Shatz, department chair and HMS Nathan Marsh Pusey Professor of Neurobiology, studied rodents during the critical period in which visual input stimulates aggressive plasticity, shaping the mesh of neural connections in the cortex and tuning the strengths of messages relayed by synapses. In mice, this period begins shortly after they open their eyes and begin to see. Previous research had determined that visual activity changes the level of expression of, or regulates, individual genes such as Brain-derived neurotrophic factor (Bdnf).

To determine whether vision regulates other genes in these rodents, Majdan and Shatz imposed abnormal visual experiences on the rodents at a variety of ages including the critical period by removing one eye and leaving the other intact. They then compared gene expression profiles of the cortex supporting the open eye to that of the missing eye. They found that Bdnf is not alone-visual input changes the levels of expression of ten additional genes, dubbed the "common set," at all ages investigated. By chemically inhibiting a MAP kinase already known to be linked to several common set genes, they found that this kinase acts as a relay, regulating these genes in response to visual activity.

The researchers found other sets of genes superimposed on this core pathway, but these sets are turned on and off by vision at specific ages before, during and after the critical period and into adulthood.

"This suggests that sensory experience regulates different genes in your brain depending on your age and past experience," said Shatz. "Thus, nurture, our experience of the world via our senses, acts through nature, sets of genes, to alter brain circuits."

These discoveries may lead to new ways of thinking about genetic therapies to correct early vision disorders. Because the brain is so altered by abnormal vision, restoring vision to a child afflicted with cataracts or strabismus, an eye misalignment which can impair vision, may not be enough to correct the damage. Nor will treatment involving single gene replacement.

"We need to try to find the major switches that turn on genes in the downstream network as opposed to looking at each element of the network and designing therapy based on each gene," said Shatz.

This study helps explain why it is that children learn so quickly and easily, and it lends credence to the idea that, in adults, mental activity leads to mental agility.

"It is amazing that, even in our oldest mice we saw genes regulated by vision. Genes in the brain change with experience at every age, forming a basis for our ability to learn and remember even in adulthood," said Shatz.

Humans perceive more than they think they do

Sat, 15 Apr 2006 18:22:00 PST

( from http://www.rxpgnews.com ) Faces tell the stories in UC Riverside Professor Larry Rosenblum's ecological listening lab, as volunteer test subjects show that they can "read" unheard speech -- not just from lips, but from the simple movements of dots placed on lips, teeth and tongue.

They can also recognize people's voices just from seeing their faces, and vice versa, and seem to be able to distinguish among a variety of rooms on campus just from their echoes.

"We get people ready for a test and tell them what we want them to do, and a lot of them think there's absolutely no way they'll be able to do that," said Rosenblum, whose field is perceptual psychology. "Some are very surprised when it turns out that they can."

Rosenblum has given test subjects quite a few such surprises. For example, participants in his work have shown that they can determine the locations of objects by listening to echoes as noise bounces off them. Other test subjects have used room echoes to figure out where they are on campus -- blindfolded.

Rosenblum's research explores speech, faces and hearing from an ecological perspective. Ecological psychologists study the ways humans perceive and act in natural environments. The emphasis is on identifying the information available to people's senses, rather than the mental processes by which they interpret it, he said.

"One thing these projects all have in common is the 'wow factor,'" Rosenblum said of his work in audio speech, visual speech and face recognition. Test subjects routinely glean more information than they expect from faces. "We all read lips to some degree, even when we don't know we're doing it," Rosenblum said. "We also read faces. The ways people's faces move as they speak adds to what we comprehend."

The ambient sound in any room also offers more information than people might expect, Rosenblum said. One experiment asked subjects to listen to recorded sounds and try to recognize where on campus the recordings were made.

"We picked different places -- a men's bathroom, the old gym, a walk-in closet -- and it turns out that people are terrific at it," Rosenblum said. In another experiment, Rosenblum and his team showed 18 UC Riverside undergraduates three shapes they would be attempting to identify -- a triangle, a disc and a square cut from sound-insulating foam board covered with black tape.

The undergrads also saw an array of eight horn-style loudspeakers that the shapes would block, and were told that the speakers would make a white-noise sound. Blindfolded, they were asked to identify which shape was positioned in front of the loudspeakers.

"Our results show that listeners can identify the shape of sound-occluding objects at better than chance levels, with some listeners displaying near-perfect performance," Rosenblum said.

That research, he said, seeks a better understanding of how human hearing is affected by silent objects. His projects are all motivated by theoretical questions rather than a quest for a particular application, Rosenblum said, but real-world considerations are important.

"We discuss practical applications in papers so engineers can use them in the work they do, whether it's designing computer software or rehabilitation programs for the blind or the deaf."

Specific Mechanisms May Not Exist For Facial Recognition

Fri, 07 Apr 2006 03:59:00 PST

( from http://www.rxpgnews.com ) Although the human brain is skilled at facial recognition and discrimination, new research from Georgetown University Medical Center suggests that the brain may not have developed a specific ability for understanding faces but instead uses the same kind of pattern recognition techniques to distinguish between people as it uses to search for differences between other groups of objects, such as plants, animals and cars.

The study, published in the April 6 edition of the journal Neuron, adds new evidence to the debate over how the brain understands and interprets faces, an area of neuroscience that has been somewhat controversial. Because the process of facial perception is complicated and involves different and widespread areas of the brain, there is much that remains unknown about how humans perform this task.

We found that faces arent special in the way many scientists once thought, says Maximilian Riesenhuber, PhD, assistant professor of neuroscience and senior author of the study. Rather, they are particular group of objects which the brain has learned to distinguish very well, much as it would for any other similar objects that are critical to human survival and communication.

Riesenhuber hopes that integrative research of this kind will help scientists better understand the neural bases of object recognition deficits in mental disorders, such as autism, dyslexia or schizophrenia. People with autism, for example, experience difficulty with recognizing faces, which might be caused by a defect on the neural level. Breakthroughs in this kind of research could someday lead to targeted therapies for the millions of people who suffer from these disorders.

The findings are exciting because we are now going to apply this technique to probe the neural bases of face perception deficits in autism, Riesenhuber said.

Because humans are so talented in recognizing faces, many in the scientific community have argued that the brain has developed unique mechanisms for understanding and distinguishing them. However, Riesenhuber and his team thought that a different model could help explain some of the existing knowledge about facial recognition, including a behavioral phenomenon known as the inversion effect, which has shown that turning a picture upside down has a strong effect on peoples ability to recognize faces whereas the ability to recognize other objects, such as houses, is affected only slightly.

We think that this is because we are face experts, having learned over many years to spot fine differences in upright faces, but not in inverted faces. That experience makes faces unique, but theres nothing scientifically special about faces, Riesenhuber says.

The Georgetown scientists hypothesized that facial recognition does not rely on face-specific mechanisms but instead uses the same neural mechanisms for faces that are used to discriminate other objects. Over the years, because of the importance of facial identity and expression for social communication, humans have simply developed a strong talent for recognizing and distinguishing faces. This experience with faces then leads to the learning of a population of neurons finely tuned to different faces, Riesenhuber says.

The researchers tested their theories using a computational model previously developed by Riesenhuber and his team to predict how different neurons would react during the recognition of non-face objects. They then showed that this simple model, even though not developed for face recognition, could quantitatively account for the inversion effect and make predictions about how selective the group of face neurons should be to explain human performance, which provided further evidence that it was unnecessary to postulate any kind of special processing in the brain for faces.

The researchers then tested these predictions against experimental data measured in a functional Magnetic Resonance Imaging (fMRI) machine, a high-powered imaging technology that can measure the brain activity of test subjects, and by other behavioral techniques. Subjects were shown pairs of images of similar human faces that had been morphed using computer graphics software, while the researchers observed how brain activation changed for more or less similar pairs of faces.

They found that a small group of neurons in the fusiform face area, an area of the brain generally thought to be responsible for face recognition, was highly selective for different faces, just as the model predicted they would behave.

We knew that the fusiform face area is highly involved and necessary for us to understand faces, but we did not know what kind of processing was going on inside that black box, he said. By using a computational model to quantitatively link neuronal processing, brain imaging and behavior, we now have a mechanistic model describing which neurons are involved and how they are behaving when we look at faces.

Scent of fear impacts cognitive performance

Mon, 03 Apr 2006 06:50:00 PST

( from http://www.rxpgnews.com ) The chemical warning signals produced by fear improve cognitive performance, according to a study at Rice University in Houston.

Women who were exposed to chemicals from fear-induced sweat performed more accurately on word-association tasks than did women exposed to chemicals from other types of sweat or no sweat at all. The study was published this month in the journal Chemical Senses.

"It is well-documented in the research literature that animals experiencing stress and fear produce chemical warning signals that can lead to behavioral, endocrinological and immunological changes in their fellow animals of the same species, but we wanted to see if this applies to humans as well," said principal investigator Denise Chen, assistant professor of psychology at Rice.

For the study, Chen collected samples of sweat from research volunteers who kept gauze pads in their armpits while they watched videos of horror movies and nonthreatening documentaries. The sweat samples were then stored in a freezer until needed for the study.

Next, Chen had 75 female students between the ages of 18 and 22 respond to 320 pairs of words that flashed for three seconds each on a computer screen. For each pair, the participants had to press a key to indicate whether the words were associated with each other (for example, arms and legs) or not (arms and wind). Some of the words were associated with threatening or fear-related topics, like weapons.

Each participant had a piece of gauze attached above their lips so that they were exposed to either chemicals from sweat or none at all during the tests. Chen compared how the chemicals from sweat impacted the speed and accuracy of participants' results on the word-association tests.

When processing meaningfully related word pairs, the participants exposed to the fear chemicals were 85 percent accurate, and those in either the neutral sweat or the control (no-sweat) condition were 80 percent accurate. "The subjects in the fear condition were six percent more accurate, which is a statistically significant difference," Chen said.

When processing word pairs that were ambiguous in threat content, such as one neutral word paired with a threatening word or a pair of neutral words, subjects in the fear condition were 15 to 16 percent slower in responding than those in the neutral sweat condition, and this difference was statistically significant. Chen's theory is that the chemicals from fear-induced sweat prompted subjects to be more cautious.

The research participants were not aware of the nature of the smells, and the smells did not differ on the intensity or pleasantness ratings.

"We demonstrated that in humans, chemical signals from fear facilitated overall accuracy in identifying word relatedness independent of the perceived qualities of the smells," Chen said. "The effect may arise from a learned association, including greater cautiousness and changes in cognitive strategies."

"Human olfaction is a young, vibrant field," Chen said, noting that the behavioral study of this subject is still in the early stage. "Olfactory receptors were discovered in the early 1990s. We now know that olfaction involves hundreds of receptors."

Results like these from Chen's behavioral research and studies from other labs form an integral part of a multipronged approach to the understanding of human olfaction.

Older people with stronger cognitive skills walk at a safer pace

Mon, 27 Mar 2006 16:39:00 PST

( from http://www.rxpgnews.com ) Psychologists wanting to help old people safely cross the street and otherwise ambulate around this busy world have found that from age 70 and up, safe walking may require solid "executive control" (which includes attention) and memory skills. For the old, slow gait is a significant risk factor for falls, many of which result in disabling fractures, loss of independence or even death. The finding may help explain why cognitive problems in old age, including dementia, are associated with falls. Cognitive tests could help doctors assess risk for falls; conversely, slow gait could alert them to check for cognitive impairment.

Roee Holtzer, PhD, and his colleagues conducted a cross-sectional study of 186 cognitively normal, community-dwelling adults aged 70 and older at New York City's Albert Einstein College of Medicine. Gait speed was tested with and without interference. In the interference conditions, participants had to walk while reciting alternate letters of the alphabet.

Performance on cognitive tests of executive control and memory, and to a lesser extent of verbal ability, predicted "gait velocity" (walking speed) tested without interference. For gait velocity tested with interference, only executive control and memory were predictive. Adding interference to the tests of gait allowed the researchers to better simulate the real world, in which walkers continually deal with distractions. The authors conclude that executive control and memory function are important when the individual has to walk in a busy environment.

The findings suggest that in old age, walking involves higher-order executive-control processes. That is, the intersecting cognitive and motor processes involved in walking may both rely on a common brain substrate, or set of structures. As a result, changes in that substrate would affect both cognition and gait.

Falls are a serious public-health issue for an aging population. Many older people are aging in the suburbs, where traffic conditions are often not designed for pedestrians of any age. And in cities, traffic lights at busy intersections are not usually timed to give people with slower perceptions and reflexes more time to safely cross the street.

Holtzer says that risk assessment and prevention programs for falls, which have typically focused on balance, strength and gait but not cognitive function, have had limited success. Given the new research, he posits that cognitive and neuropsychological performance, plus gait, could both factor into risk assessment and intervention design. What's more, cognitive rehabilitation and/or medication targeting cognitive functions such as executive control and memory might, among other benefits, reduce the risk of falling in people at risk.

Future study is needed to follow people through the life span to see how age affects the relationship between cognitive functions and gait. Holtzer cites evidence that gait is more automatic and less effortful in young than old people and points out that even within the narrow age range of his study's participant sample, each additional year tightened the relationship between cognitive function and gait velocity.

Switch for brain's pleasure pathway found

Thu, 23 Mar 2006 18:04:00 PST

( from http://www.rxpgnews.com ) Amid reports that a drug used to treat Parkinson's disease has caused some patients to become addicted to gambling and sex, University of Pittsburgh researchers have published a study that sheds light on what may have gone wrong.

In the current issue of Proceedings of the National Academy of Sciences, Pitt professor of neuroscience, psychiatry, and psychology Anthony Grace and Pitt neuroscience research associate Daniel Lodge suggest a new mechanism for how the brain's reward system works.

The main actor in the reward system is a chemical called dopamine. When you smell, touch, hear, see, or taste a pleasurable stimulus, the dopamine neurons in your brain start firing in bursts. So-called "burst firing" is how the brain signals reward and modulates goal-directed behavior. But just how the stimulus you perceive causes neurons to switch into or out of this mode has been a mystery.

Using anesthetized rats, Lodge and Grace found that one area in the brain stem, known as the laterodorsal tegmental nucleus, is critical to normal dopamine function.

"We've found, for the first time, the brain area that acts as the gate, telling neurons either to go into this communication mode or to stop communicating," says Grace. "All the other parts of the brain that talk to the dopamine neurons can only do it when this area puts them into the communication mode."

As a result, disruption in that area may play a major role in dopamine-related brain function, both in normal behaviors and psychiatric disorders.

The brain area identified by the Pitt researchers is regulated by the "planning" part of the brain, the prefrontal cortex (PFC), thereby providing a powerful indirect means for the PFC to affect the activity of dopamine neurons. Such a link could explain how changes in the PFC, seen in disorders like schizophrenia and drug addiction, disrupt the signaling of dopamine neurons.

'Executive' monkeys influenced by other executives, not subordinates

Thu, 23 Mar 2006 17:47:00 PST

( from http://www.rxpgnews.com ) When high-ranking monkeys are shown images of other monkeys glancing one way or the other, they more readily follow the gaze of other high-ranking monkeys, Duke University Medical Center neurobiologists have discovered. By contrast, they tend to ignore glance cues from low-status monkeys; while low-status monkeys assiduously follow the gaze of all other monkeys.

The discovery represents more than a confirmation of what most people believe about their bosses, said the researchers. The findings reveal that gaze-following is more than a reflex action; that it also involves lightning-fast social perception.

Such a discovery in monkeys gives the researchers an invaluable animal model that enables them to tease apart the reflexive-versus-social mechanisms that govern behavior, they said.

In particular, they can begin to understand the physiology and neural machinery of status, they said. Further animal studies will enable them to use drugs and genetic analysis to figure out what hormonal and/or genetic influences determine who becomes the monkey or human equivalent of Donald Trump, and who becomes a Woody Allen.

The researchers -- graduate student Stephen Shepherd, postdoctoral fellow Robert Deaner and Assistant Professor of Neurobiology Michael Platt -- published their findings in the Feb. 21, 2006, issue of Current Biology. The research was supported by the Cure Autism Now Foundation and the National Institute of Mental Health.

"By and large, most studies of gaze-following in humans supported the idea that it was a reflexive attention mechanism," said Platt. "People in those studies would tend to shift their attention where they saw another person looking, even if it wasn't predictive of some event happening around them. And people didn't seem able to inhibit or control their reaction." However, he said, there were hints that gaze-following didn't have all the features of a purely reflexive action, but these were only hints.

Such hints -- as well as previous studies in the Platt laboratory -- led Shepherd and Platt to explore whether social stimuli might also play a role in such decisions. Those previous studies showed both that monkeys will follow the gaze of other monkeys and that they will forego a juice reward to look at high-status monkeys.

Said Shepherd, "It seemed reasonable to me that in the natural environment monkeys would preferentially follow some individuals' gaze and not others. High-status monkeys, for example, do more to determine where the group is going to go. So there's more information to be gleaned by finding out where high-status individuals are looking. Also, it's fairly important, if you're a low-ranking macaque, not to compete with a high-ranking individual, so you want to know where they're paying attention."

In the experiments, Shepherd showed macaque monkeys images of monkeys known to be of higher or lower status than themselves. The images depicted the monkeys looking left or right. Immediately after each image, a target was flashed onto the screen, randomly in the direction the monkey image was looking or in the opposite direction. The monkeys were given juice rewards for their participation in each trial.

After a large number of trials, the researchers statistically analyzed whether status played a role in the monkeys' tendency to follow the gaze on the screen. They found that the high-status monkeys were significantly more likely to follow the gaze of other high-status monkeys than low-status monkeys; while the low-status monkeys tended to follow the gaze of all the other monkeys.

However, noted, Shepherd and Platt, it was entirely possible that low-ranking monkeys might be too anxious at seeing images of high-ranking images, and would avoid eye contract altogether.

"But our results were pretty striking," said Shepherd. "Low-ranking macaques are extremely fast to follow gaze, while the high-ranking monkeys were pretty blasé about it, being slower to respond."

Said Platt, "So, now we have an excellent model of how temperament or status can modulate the strength of these two seemingly independent attention systems -- cognitive and reflexive -- in the brain. We can begin to trace the neural pathways by which social information feeds into the structures that control the eyes. And, we can explore whether such influences as hormonal levels, particularly testosterone, influence ranking. For example, we can manipulate testosterone levels, or give anxiety-reducing drugs, to determine an effect on social status, using gaze-following as a measure."

The neurobiologists' basic studies could also have application to understanding the origins of autism, said Platt. One theory, for example, holds that high levels of testosterone in utero cause "hypermasculinization" of the brain, which suppresses the reflexive ability to orient socially -- a characteristic of autism, he noted. Also, he said, such studies could aid understanding a wide range of disorders such as social anxiety.

More broadly, said Shepherd, such studies in monkeys will enable greater insight into the basic machinery of social interaction.

"Thanks to a combination of molecular and behavioral studies, we're starting to be able to investigate the neural machinery that allows humans to empathize, to form strong social bonds, to do things like share food and to cooperate," he said. "Besides suggesting ways of diagnosing or assisting people with autism and other disorders, such studies are also a means of understanding what enables us to be social."

Manipulating Cell Receptor Alters Animal Behavior

Wed, 22 Mar 2006 08:16:00 PST

( from http://www.rxpgnews.com ) Researchers at the University at Buffalo and the University of Pennsylvania were the first to demonstrate that two intracellular events, both stimulated by the same cell receptor, can provoke different behaviors in mammals.

The broad implication of the findings may alter the way behavioral neuroscientists think about sub-cellular underpinnings of mammalian behavior, according to the researchers.

Daniels says, "The research highlights the importance of intracellular events in the regulation of behavioral states and provides new information about the means through which a single hormone can influence multiple mammalian behaviors like learning and memory, eating, drinking, reproduction and social interaction."

The study examines intracellular signaling pathways stimulated by AT1, a receptor for angiotensin, a polypeptide hormone that regulates internal equilibrium among body fluids.

By using drugs to effect these neural signaling pathways in animal subjects, the team was able manipulate this equilibrium, a finding that Daniels says provides a better understanding of the regulation of blood pressure, and body fluid composition, and could lead to new strategies for treating cardiovascular diseases.

The study of intracellular events in the field of behavioral neuroscience has blossomed over the past 20 years as a result of increased NIH funding for neuroscience research and general strides in

molecular biology and technology that permit scientists to examine exactly how cells function at the molecular level.

Daniels explains that the kidneys and lungs produce enzymes that eventually provoke production of angiotensin. It previously was known that angiotensin has robust behavioral effects on animals, causing them to drink water and consume salt. It was also known that angiotensin acts on the surface of cells by binding to receptor molecules, which, in turn, activate proteins and small molecules inside the cells that form "signaling pathways" to cause further cellular changes.

"In our study," he says, "we wanted to examine the connection between these intracellular changes and behavior by looking at the function of two particular signaling pathways that are activated by the receptor for angiotensin."

"We gave the animals a drug that bound the AT1 receptor and activated one signaling pathway, which activates a protein inside the cell called MAP kinase, but didn't activate another pathway, which increases levels of something called IP3 inside the cell," Daniels says. "Surprisingly, the animals given this drug increased their salt intake without increasing their water intake.

"This supports our hypothesis that intracellular signaling pathways stimulated by the activation of angiotensin receptors can be separated based on behavioral relevance," he says, "something that had not been shown before."

"Understanding how signaling pathways work to regulate the ingestion of water and salt may shed light on how similar events affect other behaviors, including learning and memory, feeding, reproduction and social interactions.

Daniels says the regulation of behavioral states by angiotensin "is a well-studied problem that has provided a wealth of information about the interface between peripheral hormones and central control of behavior.

"A good deal of attention had been paid to the intracellular signaling pathways under the control of the receptors for angiotensin," he says, "but our research makes strides toward understanding how these processes mechanistically affect behavior."

Daniels's research in behavioral neuroscience focuses on the genomic and neural substrates of ingestive behaviors critical for the maintenance of body-fluid, cardiovascular and energy homeostasis. Specific areas of interest include the neural circuits that contribute to these behaviors and the intracellular events that occur at various nodes within the circuits pathways.

Morphine addiction and the tendency to explore linked

Wed, 22 Feb 2006 01:13:00 PST

( from http://www.rxpgnews.com ) A team of researchers from the UAB has found experimental evidence in rats showing a link between addiction to morphine and the tendency to explore perseveringly. This is the first time a direct relationship has been found without other psychological characteristics, such as anxiousness, that might affect results. Published in Behavioural Brain Research, the results of this study are useful for planning preventative strategies in the risk population.

The tendency to use drugs depends on each individual person. Not all those who have access to drugs become addicts, therefore there may be personality characteristics that influence their use. One such characteristic is the pursuit of new sensations found in people that like looking for risk at all times. Although some studies have already suggested a link between these people and a higher probability of becoming drug addicts, shopaholics or gambling addicts, until now no study has objectively found a direct relationship without the influence of other psychological factors, such as anxiousness.

A team of researchers from the Institute of Neuroscience, the Department of Psychobiology and Health Sciences Methodology and the Department of Cellular Biology, Physiology and Immunology, directed by Roser Nadal and Antonio Armario, has shown scientifically through experiments with rats that addiction to morphine is related to a tendency to explore perseveringly and to search for new sensations. Using mazes and cages, the scientists observed in their experiments that the animals with a greater tendency to explore are more inclined towards an addiction to morphine.

The researchers had classified the rodents according to whether they had a tendency to explore repeatedly a new situation (persevering explorers) or they became disinterested in the new situation within a short amount of time. This was done by placing them in a circular corridor they had never seen before and observing their behaviour. Only the persevering animals that persistently explored their new environment had a preference for being administered morphine. It was also observed that other personality characteristics in the rats, such as anxiousness or fear, are unrelated to morphine addiction. This is the first time a relationship has been observed between addiction and a tendency to explore without other characteristics appearing that could also increase the likelihood of an addiction.

Experimental research into addictions often uses rodents, rats and mice. According to Roser Nadal, "the animal model used is extremely reliable, giving us thorough, methodical results that can to a certain extent be applied to humans without the need to experiment directly upon them".

This research, published in Behavioural Brain Research, may help to focus preventative strategies against addiction towards those most at risk, according to their personality. "The results could be particularly useful in prevention campaigns for children, who are going through the period with the highest risk," explains Doctor Nadal.

To determine a rat's level of addiction to morphine, the researchers used the place-conditioning technique. In these tests, a special cage is used that has two very different compartments, with a distinct colour, feel and smell. The animal is placed in a compartment after being injected with the drug and is left to experiment the effects of the drug and associates them with the specific characteristics of the the compartment of the cage. On a different day, the animal is injected only with a placebo (the liquid that was used to dissolve the drug, eg, water and salt) and is placed in the other compartment of the cage. When this has been done several times over the period of a few days, the rat is left free and we observe which of the two compartments it prefers. The more the animal likes morphine, the more time it will spend in the compartment that it associated with the effects of this drug, and this gives us an indication of the rat's addiction to the drug.

New study shows how self-prophecies may help

Sun, 12 Feb 2006 18:51:00 PST

( from http://www.rxpgnews.com ) By now, most of us have probably forgotten about our New Year's resolutions. But there's still hope: New research from the March 2006 issue of the Journal of Consumer Research shows that when people predict that they will do a socially good deed (such as recycling), the chances of them actually doing the good deed increases.

"A clear benefit of the self-prophecy technique is its simplicity: a question followed by a simple "yes" or "no" elicits behavioral change," explain Eric R. Spangenberg and David E. Sprott (Washington State University). For some of us, their results may also provide insight as to why we seem to have more trouble than others sticking to resolutions.

According to Spangenberg and Sprott, the "self-prophecy effect" affects some people more than others. The researchers categorized people according to level of self-monitoring, or how much they notice their own behavior being affected by the situations they are in. Low self-monitors pay more attention to their own dispositional qualities (such as being a responsible person) than to the circumstances of situation, and have been consistently shown to respond to appeals to values. High self-monitors are more aware of the situational factors and are more influenced by appeals to status.

After grouping subjects as low or high self-monitors, the researchers examined the effects of self-prediction on the subjects' willingness to either commit to a health-and-fitness assessment or donate time to the American Cancer Society. Confirming the authors' predictions, the results from two experiments showed, "â¦stronger self-prophecy effects for low (compared to high) self-monitors."

The authors believe that the threat to one's own self-conception is crucial to the self-prophecy effect: "A self-prediction needs to confront the self-concept of the person making the prediction, as it does with low self-monitors," explain Spangenberg and Sprott.

Guilt and fear motivate better than hope

Sun, 12 Feb 2006 18:46:00 PST

( from http://www.rxpgnews.com ) "Smoking pot may not kill you, but it will kill your mother," says an ad from the Partnership for a Drug-Free America. In the first empirical work to examine both stated intentions and actual behavior, researchers argue that this sort of negative message â evoking both fear and guilt â is a far more effective deterrent to potentially harmful behavior than positive hopeful or feel-good messages.

"Making people feel good is less important than making people feel accountable when it comes to making wise decisions about self-protection," explain Kirsten A. Passyn (Salisbury University) and Mita Sujan (Tulane University) in the March 2006 issue of the Journal of Consumer Research. "Our work separates intentions from implementation and clarifies the role of emotions in this process."

Whether it involves persuading people to use sunscreen or eat high fiber foods, good intentions can be elicited by a variety of appeals. However, getting people to actually follow through on these intentions and change their behavior requires appeals combining fear and an emotion high in self-accountability, such as regret, guilt or challenge.

"This research suggests a new emotion-based approach to encouraging a wide range of health protection behaviors," say Passyn and Sujan. "We illustrate the critical role of emotions in persuasion, especially for translating tendencies into action."

How the brain makes a whole out of parts

Thu, 19 Jan 2006 17:57:00 PST

( from http://www.rxpgnews.com ) When a human looks at a number, letter or other shape, neurons in various areas of the brain's visual center respond to different components of that shape, almost instantaneously fitting them together like a puzzle to create an image that the individual then "sees" and understands, researchers at The Johns Hopkins University report.

A team from the university's Zanvyl Krieger Mind/Brain Institute describes the complex but speedy process in detail in a recent issue of the journal Neuron.

The question of how the brain sees, recognizes and understands objects is one of the most intriguing in neuroscience, associate professor and paper co-author Charles E. Connor said.

"This may not even seem like a scientific question to some people, because seeing is so automatic and we are so good at it far better than the best computer vision systems yet devised," Connor said. "That is because a large part of the human brain is devoted to interpreting objects in our world, so that we have the necessary information for interacting with our environment.

"Vision doesn't happen in the eye," Connor said. "It happens at multiple processing stages in the brain. We study how objects are signaled or encoded by large populations of neurons at higher-level stages in the object-processing part of the brain."

The report, based on recordings of nerve cells in the visual cortex of macaque monkeys, reveals that neurons in the higher-level visual cortex at first respond to a visual stimulus "somewhat indiscriminately," signaling all the individual features within a shape to which they are sensitive. For instance, a particular neuron may respond to objects with either a concave fragment at the top or a convex fragment at the bottom. At this point, the neural signals are ambiguous; the brain doesn't know whether the concavity, the convexity or both are present.

Milliseconds later, however, neurons begin to react exclusively to combinations of shape fragments, rather than to individual fragments. In other words, the brain begins to put the pieces together to form larger sections, in the same way that an artisan might fasten discrete shards of stained glass to create a design.

"Humans do a rough categorization of objects very quickly," Connor said. "For instance, in just a tenth of a second, we can recognize whether something we see is an animal or not. Our results show that this immediate, rough impression probably depends on recognizing just one or more individual parts of what we see. Fine discriminations such as recognizing individual faces take longer to happen, and our study suggests that this delay depends upon emerging signals for combinations of shape fragments. In a sense, the brain has to construct an internal representation of an object from disparate pieces."

In the long term, understanding exactly how the brain processes information may lead to neural prostheses artificial replacements for lost sensory, motor and perhaps even memory and cognitive functions. In the short term, such work is driven by curiosity about one of the fundamental mysteries: how the brain works.

"Our ability to see is one of the great evolutionary accomplishments of the human brain," Connor said. "We still don't know how the visual system accomplishes this marvel of information processing. Such experiments are beginning to reveal how large networks of neurons in the brain extract meaning from the eye image."

Link in brain between sight and sound perception

Thu, 19 Jan 2006 15:57:00 PST

( from http://www.rxpgnews.com ) Just imagine listening to someone talk and also hearing the buzz of the overhead lights, the hum of your computer and the muffled conversation down the hallway. To focus on the person speaking to you, your brain clearly can't give equal weight to all incoming sensory information. It has to attend to what is important and ignore the rest.

Two scientists at the Stanford University School of Medicine have taken a big step toward sorting out how the brain accomplishes this task. In the Jan. 19 issue of Nature, the researchers show that a mechanism for prioritizing information - previously reported only in primates - is also used by birds.

"What our experiment demonstrates is a fundamental principle of how the brain pays attention," said the paper's senior author, Eric Knudsen, PhD, the Edward C. and Amy H. Sewall Professor of Neurobiology. "The promise here is that because we are doing this in owls, we can get at the mechanisms of how this works."

The study determined that the circuits in the brain that process auditory information are influenced powerfully by the circuits that control where the animal is looking-the animal's direction of gaze.

"The ability to hear and the direction of gaze aren't necessarily linked," said the paper's first author, postdoctoral scholar Daniel Winkowski, PhD. Sounds originating from any direction don't require visualization to be heard. "It's exciting to find that the circuits in the brain that control gaze direction affect how the brain processes auditory information," he added.

With funds from the National Institutes of Health, Winkowski and Knudsen used electrodes to stimulate the area of the brain responsible for controlling the direction of gaze in barn owls, and then studied how that affected the neural responses in regions of the brain that process auditory information. When the gaze control circuit was activated, they found that the owls' auditory system responded more strongly and more selectively to sounds that came from the same spatial location as that encoded by the stimulated site. The same stimulation suppressed the auditory system's response to sounds coming from other locations.

Selecting certain kinds of information to be processed, while ignoring others, is the root of attention. What was previously known about the mechanism of attention was based on research done by other scientists - including assistant professor of neurobiology Tirin Moore, PhD - who have looked at how monkeys focus their attention on things they see. These researchers have found that when a monkey decides to turn its eyes, the regions of the brain that process visual information increase their responses to objects that the monkey is about to look at and decrease their responses to all other objects in the world.

Finding that auditory responses can be regulated by the circuits that control gaze in barn owls suggests that the brain uses a common strategy to focus attention that spans different types of animals and different parts of the brain.

"This paper opens the floodgates for studying a wide range of species," Knudsen said. "The fundamental mechanisms are probably going to be the same in all vertebrates, as even frogs and fish have gaze control." All animals have to be able to attend to certain stimuli and ignore others.

"Now that we have found that the principle applies in owls as well as monkeys, we can figure out the mechanisms of how the brain manages attention," said Winkowski. In owls, the circuits being examined are amenable to manipulations that will allow researchers to determine what mechanisms are involved and which neurotransmitters and neurotransmitter receptors are used in signaling attention.

"Relatively nothing is known about how the brain increases and decreases signaling," Winkowski said. "We want to discover the cellular mechanisms of how attention works."

"Once we learn the circuitry for attention, we plan to use that to drive learning in an efficient way," said Knudsen. He added that they eventually hope to show that they can make adjustments in the circuits of the owls' brains that will lead to improved performance in the owl.

Understanding the mechanisms of attention naturally leads to the possibility of applying their knowledge to human disorders of attention, learning and schizophrenia. "If you understand mechanistically how something works, then you will know how best to fix it," said Knudsen. "It's like with a car; if you know in detail how it is built, then you can fix anything that goes wrong with it."

The cognitive cost of being a twin

Mon, 21 Nov 2005 20:15:00 PST

( from http://www.rxpgnews.com ) Social and economic circumstances do not explain why twins have significantly lower IQ in childhood than single-born children, according to a study in this week's BMJ.

Researchers studied 9,832 single-born children and 236 twins born in Aberdeen, Scotland between 1950 and 1956, using a previous child development survey as a base. They also gathered further information on mother's age at delivery, birth weight, at what stage of the child's gestation they were born, their father's occupational social class, and information on other siblings.

They found that at age seven, the average IQ score for twins was 5.3 points lower than that for single-born children of the same family, and 6.0 points lower at age nine.

The study also showed that taking into account factors such as the child's sex, mother's age, and number of older siblings made little difference to the IQ gap.

Despite advances in recent years in obstetric practice and neonatal care, the authors argue that the likely explanation is because some twins have a shorter length of time in the womb than other children and are prone to impaired fetal growth.

Researchers Identified Fear Factor Protein

Sat, 19 Nov 2005 15:13:00 PST

( from http://www.rxpgnews.com ) Researchers have identified a fear factor - a protein the brain uses to generate one of the most powerful emotions in humans and animals. The molecule is essential for triggering both the innate fears that animals are born with - such as the shadow of an approaching predator - as well as fears that arise later in life due to individual experiences. Eliminating the gene that encodes this factor makes a fearful mouse courageous. The finding, the researchers say, suggests new approaches for drugs designed to treat conditions such as phobias, post-traumatic stress disorder, and anxiety.

Working in mice, the scientists, led by Howard Hughes Medical Institute investigator Eric R. Kandel at Columbia University, found that the protein stathmin is critical for both innate and learned fear. Mice without stathmin boldly explore environments where normal mice would be hesitant, and, unlike their normal counterparts, fail to develop a fear of cues that have been associated with electric shock. The scientists also found physiological changes in the brains of mice lacking stathmin that correlate to the behavioral changes they observed.

The work, published in the November 18, 2005 issue of the journal Cell, was carried out by lead author Gleb Shumyatsky, a postdoctoral fellow from Kandel's lab who is now at Rutgers University, and other scientists from Columbia, Rutgers, Harvard Medical School, and Albert Einstein College of Medicine.

Both humans and animals are born with an innate fear of certain threatening stimuli. As an example, Kandel said, If you see a train heading right at you, you get scared and run away. This is built into the genome - the capability to respond to natural threat. Furthermore, when researchers pair a naturally frightening stimulus, such as an electric shock, with a neutral signal, such as a tone, animals develop fear of the neutral tone. That is called learned fear - that's acquired, it's a form of learning, Kandel explained. In humans, stage fright, phobias, and post traumatic stress disorders are examples of learned fear.

In previous work, Kandel and his colleagues set out to determine the underlying mechanisms that encode fear in the brain. We knew from other people's work about the neural pathways involved, Kandel said, but there was little knowledge of the key genes or the detailed neural circuitry involved. So we thought we would tackle that problem.

The researchers began their studies by searching for genes that were particularly active in the amygdala, a region deep within the brain known to contribute to fear and other emotions. They zeroed in on the lateral nucleus, the portion of the amygdala that receives information from the rest of the body about fearful stimuli. They dissected out individual pyramidal cells, the principal cells in the lateral nucleus, and found two genes, known as gastrin-releasing peptide (GRP) and stathmin, that were much more active in the lateral nucleus than in a part of the brain not thought to be involved in fear, which the researchers analyzed for comparison.

Several years ago, Kandel, Shumyatsky, and their colleagues studied the first of these genes, GRP, in detail and found that it encodes a protein that inhibits the fear-learning circuitry in the brain. GRP does not, however, play a role in innate fear demonstrating that the two fear pathways are genetically distinct.

When the scientists moved on to study stathmin, they had few clues as to what role it might play in fear - if it was involved at all. When you go after a gene like this, you have no idea what behavior or biological process it may be involved in, Kandel said. I think it's the mystery of the thing that creates part of the excitement. Except for thinking that the amygdala was very likely to be involved, we had no way of knowing what the outcome would be.

An indication that stathmin might contribute to fear came when they mapped the parts of the brain where the gene was most active. They found that stathmin was highly expressed not only in the amygdala, but also in other parts of the brain's fear circuitry. It was localized not only in the pathway of the learning process, but also in the pathway of instinctive fear, Kandel noted.

To investigate stathmin's role in more detail, the researchers created mice lacking that gene, and examined the brain activity in the lateral nucleus of their amygdalas. Recent work from other labs had shown that during fear learning, the connections between the neurons in this part of the brain strengthen. In stathmin-deficient mice, however, the connections between these neurons remained virtually unchanged, despite repeated stimulation.

These results were good indications that stathmin might play a role in learned fear. To determine whether a lack of stathmin actually altered animals' behavior in situations likely to trigger fear, the scientists used several standard laboratory tests. Mice were trained to associate an electric shock with either an auditory tone or a particular location in a cage. After the training period, normal mice would freeze when they encountered the tone or location that they'd learned was likely to accompany a shock. Stathmin-deficient mice, on the other hand, seemed unnerved by those stimuli, carrying on their normal activities boldly, without fear.

From these experiments, it was clear to the scientists that stathmin was needed for fear learning. To find out whether it might also contributed to innate fear, the scientists took advantage of mice's natural fear of open spaces. Unlike normal mice, which cower on the edges of an open field and stay near the center of a plus-shaped maze, mice without stathmin were much more adventurous, readily exploring exposed areas.

The authors concluded from their experiments that stathmin is required for both innate and learned fear. Together with his lab's previous work on GRP, Kandel said, the work advances the understanding or learned fear versus instinctive fear in several ways. It shows genetically there's a fundamental difference between the two; it gives you some insight into the neural circuitry; it shows that there's an inhibitory constraint to fear; and it gives you the potential of thinking of therapeutic targets.

As drug targets, Kandel said, GRP and stathmin each present unique opportunities. One would be for learned anxiety, the other would be for instinctive. They both, I think, are reasonable - no one has worked on those as targets before. While drugs targeting stathmin would likely affect both types of fear, Kandel expects that with further work, researchers should also be able to identify genes that act exclusively on instinctive fear.

Loneliness might be Explained by Genes

Fri, 11 Nov 2005 19:29:00 PST

( from http://www.rxpgnews.com ) Heredity helps determine why some adults are persistently lonely, research co-authored by psychologists at the University of Chicago shows.

Working with colleagues in The Netherlands, the scholars found about 50 percent of identical twins and 25 percent of fraternal twins shared similar characteristics of loneliness. Research on twins is a powerful method to study the impact of heredity because twins raised together share many of the same environmental influences as well as similar genes, thus making it easier to determine the role of genetics in development.

"An interesting implication of this research is that feelings of loneliness may reflect an innate emotional response to stimulus conditions over which an individual may have little or no control," the research team writes in the article, "Genetic and Environmental Contributors to Loneliness in Adults: The Netherlands Twin Register Study" published in the current issue of the journal Behavior Genetics. Psychologists had previously thought loneliness was primarily caused by shyness, poor social skills, or inability to form strong attachments with other people.

Scholars are becoming increasingly interested in the role loneliness plays in health. Other work by John Cacioppo, the Tiffany & Margaret Blake Distinguished Service Professor in Psychology at the University of Chicago and a member of the research team, shows that loneliness is a risk factor for heart disease. Loneliness is also at the base of a number of emotional conditions, such as self-esteem, mood, anxiety, anger and sociability.

A caring environment can help lonely people overcome their feelings, but the research also shows that in some cases, the impact of heredity is stronger, said Cacioppo, who was joined in the study by Louise Hawkley, a Senior Research Scientist in Psychology at the University.

The lead author of the article was Dorret Boomsma, a Professor of Biolgoical Psychology at the Free University in Amsterdam. Boomsma is one of the world's most prominent researchers on twins and heredity. Other researchers with the project are Gonneke Willemsen of the Free University and Conor Dolan of the University of Amsterdam.

The study was based on data from 8,387 twins in The Netherlands, who have been surveyed regularly since 1991. Smaller, earlier studies done with children suggested that the tendency toward loneliness could be inherited. The Dutch-U.S. study is the first to be done on adults and shows that heredity persists in playing a role in loneliness as people age.

As part of the study, the twins were asked to rate to what extent certain descriptions applied to them, such as "Others don't like me," "I lose friends very quickly," "I feel lonely," and "Nobody loves me."

People noted a wide variety of responses to the descriptions, with 35 percent of the men and 50 percent of the women reporting moderate to extreme feelings of loneliness.

The researchers write that loneliness may have developed early in human evolution as a response by hunter-gathers facing conditions of undernourishment who may have decided not to share their food with their families. By surviving a famine, those early ancestors would be able to propagate during periods of plenty, the researchers theorized. In developing loneliness as an adaptation to survival, these early humans also developed dispositions toward anxiety, hostility, negativity and social avoidance, they said.

The research was funded by the Netherlands Organization for Scientific Research and the U.S. National Institute of Aging.

"The genetics of social behavior is an intriguing and expanding area of research," says Jeffrey W. Elias, cognitive aging specialist at the National Institute on Aging (NIA). "This study suggests there may be a genetic component to loneliness, such that people with a predisposition to loneliness may process social interaction and information differently. This is important to know as we investigate the effects of behavior and emotion on health and longevity."

We do not feel with our sensory cortices

Tue, 08 Nov 2005 21:43:00 PST

( from http://www.rxpgnews.com ) Perceiving a simple touch may depend as much on memory, attention, and expectation as on the stimulus itself, according to new research from Howard Hughes Medical Institute (HHMI) international research scholar Ranulfo Romo and his colleague Victor de Lafuente. The scientists found that monkeys' perceptions of touch match brain activity in the frontal lobe, an area that assimilates many types of neural information.

One of neuroscience's most difficult questions concerns how the brain converts simple sensory inputs to complete perceptual experiences. Many neuroscientists assume that perceptions arise in the sensory cortices, which are the first areas of the brain to process information coming in from sense organs, Romo said. Some recent research, however, has hinted that activity in other parts of the brain may also contribute to sensory perception.

When it comes to the sense of touch, a stimulus at the skin triggers an impulse that travels first to an area at the top of the brain called the primary somatosensory cortex (S1). The information then moves to other parts of the brain, where it can contribute to memory, decision-making, and motor outputs.

To explore what regions of the brain contribute to sensory perception, Romo and de Lafuente analyzed neural activity associated with the sense of touch in macaque monkeys. The researchers touched the monkeys' fingertips with a painless stimulus that sometimes vibrated and sometimes did not. The intensity of the vibration varied, so sometimes it was easy for the monkeys to tell that the vibration was on, while other times the vibrations were so weak that the monkeys couldn't always detect them. The monkeys were trained to indicate to the researchers whether the stimulus was vibrating or still, and they were rewarded with treats when they were correct.

The scientists found that activity in S1 neurons, where touch information first arrives, correlated directly with the strength of the stimulus; when the strength of the vibrations was more intense, the S1 neurons' fired more rapidly. However, these neurons' activity did not correlate with the monkeys' behavioral responses. Their firing rates were directly associated with the stimulus intensity, whether the monkeys consciously felt and responded to the stimulus or not.

Romo and de Lafuente also recorded neuronal activity in the medial premotor cortex (MPC), a region of the brain's frontal lobe that is known to be involved in making decisions about sensory information. Activity here did mirror the monkeys' subjective responses to the vibrating probe. MPC neurons responded in an all-or-none manner; they fired when the monkey thought the vibrations were thereeven if they weren'tand they didn't fire when the monkey thought the vibrations were absenteven if they were actually occurring.

These results indicate that the monkeys' perceptions arise not from brain activity in the sensory cortex itself, but from activity in the frontal lobe MPC, Romo said.

The MPC is very interesting, Romo said. Apparently, it's able to pull information from memory and from the sensory areas, and also link this activity to the motor apparatus so that the monkeys can physically indicate what they think is happening.

To clinch the MPC's association with the monkeys' perceptions, the researchers used an electrode to apply weak electrical stimulation to MPC neurons. They found that stimulating these neurons made the monkeys more likely to respond that they perceived a vibration, whether the vibrating stimulus was occurring or not.

Romo and de Lafuente also found that MPC neurons began to fire before the stimulus even touched the monkeys' fingertips. Romo believes this is because the monkey is expecting the stimulus and the neurons fire in anticipation.

I think that we do not feel with our sensory cortices, Romo said. Perceptions instead arise in higher-order brain areas from a combination of sensation, attention, and expectation. The sensory representation is [just] to confirm something that you have already thought.

Choice Blindness Experiment Sheds More Light On Decision Making Processes

Sun, 09 Oct 2005 00:17:00 PST

( from http://www.rxpgnews.com ) Researchers showed picture-pairs of female faces to the participants and asked them to choose which face in each pair they found most attractive. In addition, immediately after their choice, they were asked to verbally describe the reasons for choosing the way they did. Unknown to the participants, on certain trials, a card magic trick was used to secretly exchange one face for the other. Thus, on these trials, the outcome of the choice became the opposite of what they intended.

The researchers measured whether the participants noticed that something went wrong with their choice, both concurrently, during the experimental task, and retrospectively through a post-experimental interview. Less than 10% of all manipulations were detected immediately by the participants, and counting all forms of detection no more than a fifth of all manipulated trials were exposed. The researchers call this effect choice blindness.

Theories about decision-making generally assume that we recognize when our intentions and the outcome of our choices do not match up, but this study shows that this assumption is not necessarily correct. By shedding new light on the links between intentions and outcomes, these results challenges both current theories of decision making, and common sense notions of choice and self-knowledge.

The researchers also sought to understand if the verbal reports given by the participants differed between the faces that they actually chose, and the ones that they ended up with in a manipulated trial. "Based on common sense alone one might suspect that the reports given for normal trials and for the manipulated trials would differ in many ways", said Hall. "After all, revealing the reasons behind a choice is something we very often do in everyday life. But revealing the reasons behind a choice we did not make is a very strange thing indeed."

Choice Blindness Experiment. Photographer: Mark Hanlon

However, using a variety of measures, the researchers found that the two types of reports were remarkably similar. ''When asked to motivate their choices, the participants delivered their verbal reports with the same confidence, and with the same level of detail and emotionality for the faces that that were not chosen, as for the ones that were actually chosen'' Johansson said.

Despite the intimate familiarity we have with everyday decision making, it is very difficult to determine what we can know about this process from the 'inside', by reflection and introspection. A great barrier for scientific research in this domain is the nature of subjectivity. How can researchers ever verify the reports of the participants involved, when they have no means of challenging them? But by using choice blindness as an instrument, the researchers were able to 'get between' the decisions of the participants and the outcomes they were presented with. "Our experiment introduces an entirely novel methodology that can be used to investigate choice and introspection'' Hall said. ''This may lead to an improved understanding of the processes behind both truthful and confabulatory reports''

The maternal instinct for commitment

Thu, 06 Oct 2005 00:45:00 PST

( from http://www.rxpgnews.com ) The new study has revealed that when progesterone levels are raised during the second half of the menstrual cycle, women become more committed to their romantic partners.

Dr Ben Jones, Lecturer in the Psychology department at the University of Aberdeen, is first author of the new study published recently in the American journal Hormones and Behavior.

He said: Its well established that womens preferences for the faces, body odours, voices and behaviour of feminine men increase during the second half of the menstrual cycle when progesterone level is raised.

One interpretation of these effects is that women are particularly attracted to feminine caring and sharing men at times when raised progesterone level prepares the body for pregnancy.

This maternal self-protection instinct increases the amount of support women receive during pregnancy and helps women meet the physical and mental challenges of pregnancy more easily.

Increased commitment to their partner when the body prepares for pregnancy is important because women face many physical and mental challenges during pregnancy, such as stress and physical discomfort, and care and support probably makes coping with these challenges a little bit easier, said Dr Jones.

Professor Dave Perrett from the University of St Andrews, who lead this new study together with Dr Jones, said: Our new research shows direct links between changes in progesterone and attitudes to both relationships and male looks.

During the second week of the menstrual cycle, when the pregnancy hormone progesterone is low, women are drawn to masculinity and commitment to long-term partners falters, but for the last two weeks of the cycle when progesterone is high, women are drawn to the health and caring looks in a man and commitment to partners strengthens.

Dr Jones added: An interesting aspect of this new study is that changes in womens commitment to their romantic partners dont seem to threaten the stability of their long-term relationships.

We found that womens commitment to their romantic partners changes during the menstrual cycle but that this does not affect how happy women are with their current partner.

The group are continuing to explore the effects changes in hormone levels have on attraction and attitudes and are planning their most ambitious study yet.

Dr Jones said: We plan to recruit couples that are planning pregnancies and track their attitudes to relationships and face preferences from before conception, right through pregnancy and into the first few months of parenthood.

By using the internet to collect this data we hope to track these changes in men and women from all over the world.

Link between body and action perception revealed

Sat, 24 Sep 2005 15:35:00 PST

( from http://www.rxpgnews.com ) Psychology researchers have long understood and accepted the importance of an individual's brain activity in motor areas when interpreting the actions of others. However, much less was known about the role the body plays in helping individuals process and understand the same information. With the help of two patients suffering from an extremely rare degenerative neurological condition, a Rutgers-Newark Psychology Professor and his team of researchers have established that the body plays a significant role in helping humans to perceive and understand the actions of others.

In the article, "Understanding Another's Expectation from Action: The Role of Peripheral Sensation," that will appear in the October 2005 issue of Nature Neuroscience, Rutgers-Newark Psychology Professor Guenther Knoblich is among a group of researchers who contend that individuals use the human body's senses to understand others actions and expectations. The individuals participated in tasks that tested their ability to gauge the weight of boxes which were lifted by other individuals and their ability to infer weight expectations of the observed individuals. Their performance was compared against a control group comprised of healthy individuals.

"In order for an individual to perform a motor activity simulation, you need to know how it feels to perform the action," Knoblich notes. "The two deafferented individuals do not feel their bodies. They must see their bodies to perform the simplest actions, such as standing upright. The tasks involved individuals observing someone lifting a box and attempting to determine and report the object's weight. In some of the instances, the individuals doing the lifting were correctly informed of the boxes weight. In other instances, investigators misled the lifting person about the weight of the box. The patients and control group viewed videos and afterwards either estimated the weight of the box or reported whether or not they thought that the person lifting the box was deceived beforehand about its weight.

"We observed that there was no difference in the responses when the two groups were asked to estimate the object's weight," Knoblich explained. According to Knoblich, the patients were unable to accurately respond to the expectation task because they could not perform a motor simulation. Knoblich said these results go a long way toward establishing the view that the body's senses are critical to a human's ability to understand the actions and expectations of others.

While science questions the assumption that human cognition can be viewed as disembodied, computer-like information processing, many contemporary visual artists and performers seem to move away from abstraction to re-discover the human body as an object of art."

Women tend to model relationship behavior of their mothers

Tue, 20 Sep 2005 21:59:00 PST

( from http://www.rxpgnews.com ) Research showed that young adult women whose mothers reported cohabitation were 57 percent more likely than other women to report cohabitation themselves. In addition, daughters of cohabiting mothers tended to cohabit at earlier ages than others.

Women tend to model the behavior of their mothers when it comes to relationships, said Leanna Mellott, co-author of the study and a graduate student in sociology at Ohio State University . The likelihood that sons would cohabit was not affected by whether their mothers lived with a man outside marriage, but there were other effects: sons were more likely to cohabit if their mothers were divorced or had their first child at an early age.

While there has been a lot of research on how divorce affects children, this is one of few studies on the impact of cohabitation, said Zhenchao Qian, another co-author and associate professor of sociology at Ohio State .

As more people enter into cohabiting relationships and have children, we have to recognize that this could have long-term effects on these children as they enter adulthood, Qian said.

Mellott presented the team's findings Aug. 16 in Philadelphia at the annual meeting of the American Sociological Association. Mellott and Qian conducted the study with Daniel Lichter, a former Ohio State professor now at Cornell University .

Data for the study came from the National Longitudinal Survey of Youth, a nationally representative survey of people nationwide conducted by Ohio State 's Center for Human Resource Research. The NLSY also interviewed these participants' children.

This study included data on women in the NLSY who had children who were at least 18 years old by 2000. There were 2,426 of these young adults in this study.

Mellott said that the mothers in this study were not representative of all mothers, because they had children at a relatively young age. Other results of the study showed that young Black men were about 35 percent less likely than white men to report cohabitation, while Black women were 90 percent less likely to have cohabited than their white counterparts.

Education was another important factor, with higher levels of schooling consistently linked to lower levels of living together outside of marriage.

While religion itself was not linked to cohabitation, people who attended religious services weekly were much less likely to live together than those who attended rarely or never.

Young adults' relationships were also affected by the stability of their mothers' relationships, the study showed.

Each relationship transition for the mothers including divorce, widowhood or new cohabitation -- increased the likelihood of cohabitation by 32 percent for their sons, and 42 percent for their daughters.

We need to further study both the number and type of relationship transitions such as divorce or cohabiting for mothers and their children, she said.

Expectations have a surprisingly big effect on pain intensity

Tue, 06 Sep 2005 20:18:00 PST

( from http://www.rxpgnews.com ) The study involved 10 normal, healthy volunteers who had a heat stimulator applied to their legs while their brains were being scanned with functional magnetic resonance imaging (fMRI), a technology that shows which areas of the brain are being activated.

In a training session, researchers taught participants to expect three different levels of painful heat stimuli after a timed interval. A seven-second interval signaled a heat level that caused mild pain (115 degrees Fahrenheit), a 15-second interval signaled a heat level that produced moderate pain (118 degrees) and a 30-second interval signaled a heat level that produced severe pain (122 degrees). Since the heat stimuli were on for only 20 seconds, none of them were hot enough to cause burns or damage to the skin.

One or two days after training, participants underwent 30 different heat trials that were monitored with fMRI. About a third of the time, the researchers mixed the signals for the pain levels, so that participants were expecting one temperature, but actually received either a higher or lower temperature.

When participants expecting moderate pain were exposed to the severe heat level, their ratings of pain intensity were 28 percent lower than on the trials where they were expecting a high level of pain and actually received it. All 10 subjects had diminished pain intensity when they expected lower levels of pain.

Expectations of decreased pain powerfully reduced both the subjective experience of pain and activation of pain-related brain regions, said Robert Coghill, Ph.D., the senior author of the study and a neuroscientist at Wake Forest University School of Medicine, which is part of the Medical Center.

Brain regions activated during expectations of pain overlapped partially with those activated during pain, which suggests that there is are crucial brain regions that allow expectations to shape the processing of information from the body.

We dont experience pain in a vacuum, Coghill said. Pain is not solely the result of signals coming from an injured body region, but instead emerges from the interaction between these signals and cognitive information unique to every individual.

He said that the identification of brain regions that can allow cognitive factors such as expectations to shape incoming sensory information may lead to increased acceptance of cognitive and behavioral treatments for pain by patients, physicians and insurers.

We need to find ways to optimize these treatments, Coghill said. Pain needs to be treated with more than just pills. The brain can powerfully shape pain, and we need to exploit its power.

Factors influencing preschoolers perceptions about cigarettes and alcohol

Tue, 06 Sep 2005 06:30:00 PST

( from http://www.rxpgnews.com ) When pretending to shop for a social evening, children two to six years old were nearly four times as likely to choose cigarettes if their parents smoked and children who viewed PG-13- or R-rated movies were five times as likely to choose wine or beer, according to a study in the September issue of Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals.

Most tobacco and alcohol prevention studies target children during adolescence, the peak age for initiating alcohol and tobacco use, but early exposure to these behaviors through family members, community and social events and media may influence attitudes and expectations about alcohol and tobacco use long before children ever consider using these products themselves, according to background information in the article. Young children's attitudes have been difficult to assess because of their limited language skills.

Madeline A. Dalton, Ph.D., of Dartmouth College, Hanover, N. H., and colleagues used a role-playing scenario to assess preschoolers' attitudes, expectation and perceptions of tobacco and alcohol use and compared their observations with parent surveys on their own alcohol and tobacco use and their children's movie viewing. Children three to six years of age were given two dolls. They were asked to pretend to be one of the dolls and the researcher pretended to be the other, a friend who was invited over to watch a movie and have something to eat. When the "friend" commented that there was nothing to eat, the child was invited to "shop" at a doll grocery store. The child's purchase of alcohol and tobacco products at the "store" and subsequent inclusion of alcohol and tobacco products in the social setting were recorded. For children two years of age, the scenario was simplified to just asking the children to select a doll and take it shopping.

The children purchased an average of 17 of the 73 products in the store. Of the 120 children participating in the study, 34 (28.3 percent) bought cigarettes and 74 (61.7 percent) bought alcohol. Children were 3.9 times as likely to buy cigarettes if their parents smoked. Children were three times as likely to choose wine or beer if their parents drank alcohol at least once a month; children who viewed PG-13- or R-rated movies were five times as likely to choose wine or beer.

"Children's play behavior suggests that they are highly attentive to the use and enjoyment of alcohol and tobacco and have well-established expectations about how cigarettes and alcohol fit into social settings," the researchers report. "Several children were also highly aware of cigarette brands, as illustrated by the six-year-old boy who was able to identify the brand of cigarettes he was buying as Marlboros but could not identify the brand of his favorite cereal as Lucky Charms."

"The data suggest that observation of adult behavior, especially parental behavior, may influence preschool children to view smoking and drinking as appropriate or normative in social situations," the authors conclude. "Although it is not clear whether these expectations predict future use, the data provide compelling evidence that the process of 'initiation,' which typically involves shifts in attitudes and expectations about the behavior, begins as young as three years of age. The results from this study suggest that alcohol and tobacco prevention efforts may need to be targeted toward younger children and their parents."

Male and female voices affect brain differently

Sun, 04 Sep 2005 09:23:00 PST

( from http://www.rxpgnews.com ) Scientists at the University of Sheffield have explained the differences in the way the male brain interprets male and female voices, explaining why people who hallucinate and hear false voices almost always hear a man. It also sheds new light on the way the brain processes voices to produce an `auditory face´ that allows people to determine aspects of someone´s physical appearance based solely on the way they sound.

The paper, published online in NeuroImage, describes how scientists studied brain scans of 12 male subjects whilst they listened to male and female voices. It found startling differences in the way that the brain interprets the two sounds, with female voices causing activity in the auditory section of the brain and the male voice sparking activity in the `mind´s eye´ at the back of the brain.

Dr Michael Hunter, of Professor Peter Woodruff´s group in the Department of Psychiatry and Division of Genomic Medicine at the University of Sheffield, and co-author of the study explains, "Voices allow the brain to determine various factors about a person´s appearance, including their sex, size and age. It is much more complex than most people think and is an extremely important tool for determining someone´s identity without having to see them.

"The female voice is actually more complex than the male voice, due to differences in the size and shape of the vocal cords and larynx between women and men, and also due to women having greater natural `melody´ in their voices.. This causes a more complex range of sound frequencies than in a male voice.

"When a man hears a female voice the auditory section of his brain is activated, which analyses the different sounds in order to `read´ the voice and determine the auditory face.

"When men hear a male voice the part of the brain that processes the information is towards the back of the brain and is colloquially known as the `mind´s eye´. This is the part of the brain where people compare their experiences to themselves, so the man is comparing his own voice to the new voice to determine gender.

"People who hear hallucinatory voices usually hear male voices. Psychiatrists believe that these auditory hallucinations are caused when the brain spontaneously activates, creating a false perception of a voice. The reason these voices are usually male could be explained by the fact that the female voice is so much more complex that the brain would find it much harder to create a false female voice accurately than a false male voice.
"This research could also explain why female voices are considered to be clearer then male voices. This could be linked to the fact that female voices are interpreted in the auditory part of the brain, and are therefore more easily decoded."

Mixed results from abstinence-only intervention

Sun, 04 Sep 2005 08:28:00 PST

( from http://www.rxpgnews.com ) Abstinence-only education can influence teen sexual behavior and beliefs, according to a Case Western Reserve School of Medicine study published in the American Journal of Health Behavior.

The study examined the effectiveness of For Keeps, an abstinence-until-marriage sex education program that has been presented to more than 25,000 students at public and private schools in the Greater Cleveland area.

The goal of the curriculum, developed by Operation Keepsake is to increase abstinence beliefs and intention, increase efficacy in situational resistance, reduce early sexual experimentation and encourage renewed abstinence among teens already sexually active. The study involved 2,069 middle school students questioned about their sexual knowledge and practices before and five months after receiving the For Keeps curriculum. Students were enrolled in classrooms that were assigned to be intervention or controls (receiving the curriculum after the evaluation was completed.

Researchers led by Elaine A. Borawski, Ph.D., in the Department of Epidemiology and Biostatistics, found that after going through the program, teens reported significant increases in their HIV/STD knowledge, their personal beliefs about the importance of abstinence and their intentions to remain abstinent in the near future.

But the program did not affect students' confidence to avoid risky sexual situations, and sexually inexperienced and female students actually reported a decrease in their intent to use condoms in the future. However, no changes in condom use intentions were observed among sexually active or male students. The study also found that the program did not significantly reduce the likelihood that teens would engage in sexual intercourse or to use a condom consistently

A surprising finding revealed that while sexually active students exposed to the intervention were not more likely to abstain from sex, they did report fewer casual sex encounters and fewer sexual partners than their peers who did not receive the program.

"This community-based evaluation reveals that abstinence-only intervention can influence knowledge, beliefs and intentions, and among sexually experienced students, may reduce the prevalence of casual sex," Borawski said, adding that the intent of teens to reduce their condom use merits further study to determine long-term implications.

Psychological and behavioural reactions to the bombings in London on 7 July 2005

Tue, 30 Aug 2005 19:00:00 PST

( from http://www.rxpgnews.com ) Almost two weeks after the London terrorist attacks, the majority of Londoners reported that they were coping well with their emotional responses, finds a study published online by the BMJ.

Emotional reactions to terrorist incidents vary. High levels of stress were reported after the attacks in the United States on 11 September 2001, and after the 1995 bombing in Oklahoma City.

To assess the psychological effects of the attacks in London on 7 July 2005, researchers surveyed a representative sample of 1,010 Londoners. The interviews asked about current levels of stress and travel intentions, and took place from Monday 18 to Wednesday 20 July, before a second failed attack on Londons transport network on Thursday 21 July.

Thirty one percent of participants reported substantial stress, and 32% reported that they would now reduce the amount they used the tube, trains, buses, or go into central London.

Among other things, having difficulty contacting others by mobile phone, and believing you or a close friend or relative might have been injured or killed, were associated with higher levels of stress.

Muslims reported significantly more stress than people of other faiths, whereas being white and having previous experience of terrorism (e.g. experience of IRA terrorism in London) was associated with reduced stress.

Only 12 participants (1%) felt that they needed professional help to deal with their emotions, whereas 71% had spoken to friends or relatives about the attacks. This suggests that most people are able to turn to lay support networks after traumatic events, say the authors.

Despite some study limitations, these results are reassuring, write the authors. Although the psychological needs of those intimately caught up in the attacks will require further assessment, we found no evidence of a widespread desire for professional counselling.

Investigating the controversy about whether bisexual men exist

Thu, 25 Aug 2005 03:19:00 PST

( from http://www.rxpgnews.com ) A study published in the current issue of Psychological Science investigates the controversy about whether bisexual men exist. In terms of behavior and identity, they clearly exist as there are men who have sex with both men and women. Upon measuring genital, as well as, self-reported sexual arousal to male and female stimuli, researchers found that, in general, bisexual men did not have a strong genital arousal to both male and female sexual stimuli. Instead, they had strong genital arousal to one sex or the other, but not to both. Most of the time, bisexual men had a genital arousal pattern similar to that of gay men, with stronger genital arousal to male stimuli. However, a subset of bisexual men had genital arousal patterns similar to those of heterosexual men. In contrast to genital arousal patterns, self-reported sexual arousal of bisexual men was substantial to both sexes. The researchers interpreted their results as a lack of a bisexual arousal pattern. "Rather they [the bisexual men] seem to be interpreting or reporting their arousal patterns differently than other men do," researchers Gerulf Rieger, Meredith L. Chivers, and J. Michael Bailey state.

Self-identified heterosexual, homosexual, and bisexual male participants watched three videos--an introductory neutral (relaxing) clip and two sexually explicit films featuring two men having sex with each other and then two women with each other. The participants pressed on a lever to self-report their arousal while equipment measured their penile erection. The study reports no indication of a bisexual pattern of genital arousal, although the bisexual men did report a distinctly bisexual pattern of subjective arousal. "Male bisexuality is not simply the sum of, or the intermediate between, heterosexual and homosexual orientation," the study concludes. "Indeed, with respect to sexual arousal and attraction, it remains to be shown that male bisexuality exists."

Different event-related potentials (ERPs) to pictures and words that describe the same object

Thu, 18 Aug 2005 02:26:00 PST

( from http://www.rxpgnews.com ) A paper published in the recent issue of Psychophysiology describes differences in the brain's response (event-related potentials, or "ERPs") to pictures and words that describe the same object. In two studies, the authors evaluated how the brain reacts differently to a picture of an object or its name when people were looking for either the picture or the name in a visual display.

University students saw pictures of five simple objects and words corresponding to their names. Participants were instructed to keep a silent mental count of the appearance of a specific target. For instance, in the first study, they looked for the word "globe." Its appearance on screen created a noticeable brain response. "We found that the appearance of the word 'globe' elicited a large electrical response called the P300, a positive-going ERP that occurs about 300-500 ms after the presentation of a target, " author Todd Watson states. Although it was not a target, the picture of the globe elicited a similar (although less pronounced) electrical response. In a second study, the specified object was the picture of a globe. Again, the authors found that a picture of the globe elicited a large P300. However unlike the first experiment, the other version of the object -- the word "globe" -- failed to elicit a prominent electrical response. These intriguing results suggest that whereas a word may automatically activate a mental image of the same object (e.g., a globe), a picture does not necessarily activate its verbal name. In turn, these data suggest the possibility that processing images and words may involve distinct brain circuits that can, but do not always, "talk to" one another. These techniques could help us to understand how our brains respond differently to visual or verbal codes that describe the objects in the world around us, as well as how our brains evaluates similarity between different objects or concepts.

Financially richer people tend to be happier - Study

Mon, 15 Aug 2005 20:55:00 PST

( from http://www.rxpgnews.com ) Financially richer people tend to be happier than poorer people, according to sociological researcher Glenn Firebaugh, Pennsylvania State University, and graduate student Laura Tach, Harvard University. Their research is focused on whether the income effect on happiness results largely from the things money can buy (absolute income effect) or from comparing one's income to the income of others (relative income effect). They present their research in a session paper, titled "Relative Income and Happiness: Are Americans on a Hedonic Treadmill?," at the American Sociological Association Centennial Annual Meeting on August 14.

Firebaugh argues that, in evaluating their own incomes, individuals compare themselves to their peers of the same age. Therefore a person's reported level of happiness depends on how his or her income compares to others in the same age group. Using comparison groups on the basis of age, the researchers find evidence of both relative and absolute effects, but relative income is more important than absolute income in determining the happiness of individuals in the United States. This may result in a self-indulgent treadmill, because incomes in the United States rise over most of the adult lifespan.

"If income effects are entirely relative, then continued income growth in rich countries today is irrelevant to how happy people are on the whole," says Firebaugh. "Rather than promoting overall happiness, continued income growth could promote an ongoing consumption race where individuals consume more and more just to maintain a constant level of happiness."

Firebaugh tested what he refers to as the hedonic treadmill hypothesis, which uses a comparison of age-based cohorts. The hedonic treadmill requires a specific type of relative income effect--one where "keeping up with the Joneses" means continually increasing one's own income, because we can be sure that the Joneses are increasing theirs.

The researchers' measured the age, total family income, and general happiness of 20- to 64-year-olds using analysis from the 1972-2002 General Social Survey. They controlled for health, education, effects of getting older, race, and marital status. Happiness was measured using a self-report response of "very happy," "pretty happy," or "not too happy."

While income is important in determining happiness, Firebaugh's data found that physical health was the best single predictor of happiness, followed by income, education, and marital status. The researchers found a relative income effect--the richer you are relative to your age peers, the happier you will tend to be.

"We find with and without controls for age, physical health, education, and other correlates of happiness," said Firebaugh, "that the higher the income of others in one's age group, the lower one's happiness. Families whose income earners are in jobs with flat income trajectories are likely to become less happy over time. Thus the relative income effect observed here implies adverse effects for some individuals over the working years of their life cycles."

Prenatal alcohol exposure can lead to slower cognitive reaction times and poorer attention

Mon, 15 Aug 2005 20:39:00 PST

( from http://www.rxpgnews.com ) Decades of research have left little doubt that prenatal alcohol exposure has adverse effects on intellectual and neurobehavioral development. A recent study of the effects of moderate to heavy prenatal alcohol exposure on cognitive function confirms earlier findings of slower processing speed and efficiency, particularly when cognitive tasks involve working memory. Results are published in the August issue of Alcoholism: Clinical & Experimental Research.

"Prenatal alcohol exposure is often associated with slower reaction times and poorer attention in infancy, and some of these deficits may be at the core of poorer academic performance and behavior problems often seen later in childhood," said Matthew J. Burden, postdoctoral research fellow at Wayne State University School of Medicine and corresponding author for the study. "In cases of fetal alcohol syndrome (FAS) lower IQ scores are common, often reaching the level of mental retardation. This is because alcohol consumed by the mother has a direct impact on the brain of the fetus. However, full FAS is not required to see this impact; it is just less obvious to detect across the array of exposures found in fetal alcohol spectrum disorders (FASD), which include effects of prenatal alcohol at lower drinking levels."

Julie Croxford, graduate research assistant at Wayne State University, says there is a need for researchers to look at the damage caused by prenatal alcohol exposure at lower-than-heavy levels of drinking. "In the past, much focus was placed on studying the full-blown FAS," she said. "More recent research has considered those individuals damaged by lower levels of exposure. This is an important focus."

For this study, researchers assessed 337 African-American children (197 males, 140 females) at 7.5 years of age; selected from the Detroit Prenatal Alcohol Longitudinal Cohort, the children were known to have been prenatally exposed to moderate-to-heavy levels of alcohol. Their mothers were originally recruited between September 1986 and April 1989 during their first prenatal visit to a maternity hospital clinic. The children were assessed on processing speed and efficiency in four domains of cognitive function short-term memory scanning, mental rotation, number comparison, and arrow-discrimination processing using a Sternberg paradigm, which examines speed of completion as problems become increasingly more difficult.

"We chose these four domains because they allow us to study distinct aspects of cognition within the same cognitive framework," said Burden. "This helps to distinguish potentially specific deficits from those that are more global in nature; that way we get a better understanding of how prenatal alcohol exposure affects cognitive functioning many years later in childhood. We used the Sternberg paradigm because it indicates how fast an individual generates the correct response to a number of problems, providing an overall measure of speed; and it examines the rate at which response times increase as problem difficulty increases, providing a processing efficiency measure."

Although the alcohol-exposed children were able to perform as well as the other children when tasks were simple such as naming colors within a timed period when pressed to respond quickly while having to think about the response, their processing speed slowed down significantly.

"This suggests that processing speed deficits are more likely to occur within the context of some cognitive demand," said Burden. "We also found that prenatal alcohol exposure was associated with poorer efficiency on number processing, a finding consistent with past research showing more specific adverse effects in the arithmetic domain. Arithmetic performance may be relatively more compromised with prenatal alcohol exposure than other types of intellectual performance, such as verbal abilities. We also looked at how processing speed related to other aspects of cognition, working memory in particular. Prenatal alcohol exposure had some impact on both speed and working memory, but the effect on working memory was partly accounted for by the deficits in speed in other words, slower performance contributes in part to poorer working memory."

"The conclusion drawn here is that the reaction-time deficits associated with prenatal alcohol exposure are seen more in demanding/challenging cognitive tasks that involve the integration of working memory," said Croxford. "The real-world implications of this are that children exposed prenatally to alcohol may be able to perform simple tasks, but may struggle with tasks that are more challenging and require complex cognition and the use of working memory. This is likely to mean that these children may be more and more challenged the older they get by the demands placed on them within the school system and within their day-to-day social interactions."

Both Burden and Croxford noted that this study also examined the impact of "confounding" factors such as home environment, socioeconomic status, and current maternal drinking levels, which researchers believe may contribute to the poor outcomes seen in children exposed to prenatal alcohol.

"In this study, we accounted for more than 20 of these potentially confounding influences in the analyses," said Burden. "The effect of alcohol exposure in utero persisted above and beyond any other influences present."

What this means, said Croxford, is that alcohol itself causes specific, identifiable and permanent deficits in brain development and physiology. "This reinforces the current public health message that women should not drink alcohol during pregnancy," she said.

Burden said that he and his colleagues will continue to examine the long-term effects of prenatal alcohol exposure on the same children. "In addition to neuropsychological and behavioral measures, we will also be using electrophysiological techniques such as event-related potentials and neuroimaging (fMRI) to more directly connect cognitive performance with brain function," he said.

The effort required to correctly hear and identify words may diminish the resources needed to memorize them

Sun, 14 Aug 2005 14:20:00 PST

( from http://www.rxpgnews.com ) In a new study, Brandeis University researchers conclude that older adults with mild-to-moderate hearing loss may expend so much cognitive energy on hearing accurately that their ability to remember spoken language suffers as a result.

The study, published in the latest issue of Current Directions in Psychological Science, showed that even when older adults could hear words well enough to repeat them, their ability to memorize and remember these words was poorer in comparison to other individuals of the same age with good hearing.

"There are subtle effects of hearing loss on memory and cognitive function in older adults," said lead author Arthur Wingfield, Nancy Lurie Marks Professor of Neuroscience at the Volen National Center for Complex Systems at Brandeis University. "The effect of expending extra effort comprehending words means there are fewer cognitive resources for higher level comprehension."

"This extra effort in the initial stages of speech perception uses processing resources that would otherwise be available for downstream operations, such as encoding the material in memory or performing higher-level comprehension operations," explained co-authors Patricia A. Tun and Sandra L. McCoy.

A group of older adults with good hearing and a group with mild-to-moderate hearing loss participated in the study. Each participant listened to a fifteen-word list and was asked to remember only the last three words. All words were delivered at the same volume. Both groups showed excellent recall for the final word, but the hearing-loss group displayed poorer recall of the two words preceding it.

Because both groups could correctly report the final word, it was reasoned that the hearing-loss group's failure to remember the other two words was not a result of their inability to hear/correctly identify them. The authors interpret this as a demonstration of the effortfulness principle-- the increased effort required detracted from the cognitive processes of memorizing these words.

"This study is a wake-up call to anyone who works with older people, including health care professionals, to be especially sensitive to how hearing loss can affect cognitive function," said Dr. Wingfield.

He suggested that individuals who interact with older people with some hearing loss could modify how they speak by speaking clearly and pausing after clauses, or chunks of meaning, not necessarily slowing down speech dramatically.

Hand Movements Suggest Continuous Language Processing

Thu, 11 Aug 2005 17:08:00 PST

( from http://www.rxpgnews.com ) Michael Spivey et al. explore the use of hand movements, recorded as a continuous response, to track the temporal dynamics of cognitive language processing.

A classic, modular theory of language processing assumes that neural subsystems responsible for perception and cognition each wait until a stable, unique representation has been computed before passing that information to the next stage. An alternative model posits a continuous uptake of sensory input and then dynamic competition between simultaneously active representations.

Spivey et al. recorded the streaming (x, y) coordinates of a cursor directed by a hand-controlled computer mouse during spoken language tasks. These data were reported to be of high temporal resolution and provided smooth curves even within individual trials, so that central tendencies of group data were fairly represented.

The shapes of these trajectories gave a concrete, two-dimensional visualization of the dynamics involved in language processing, the authors say, and the results add further evidence for the continuous-uptake cognitive model.

Significant long-term impact of stalking found on victims' psychological health

Sun, 07 Aug 2005 14:40:00 PST

( from http://www.rxpgnews.com ) The first community-based study of its kind in Germany has confirmed findings from other countries, including the UK, the USA and Australia, which reveal a substantial incidence of stalking.

Furthermore, the significant long-term impact of stalking on the victims' psychological health found in this study suggests that this form of harassment deserves more attention in future community mental health research.

A postal survey was sent to a random sample of 1000 men and 1000 women aged 18-65 living in Mannheim, a middle-sized German city with 330,000 inhabitants. 400 women and 279 men responded. Their responses were compared with those of a matched sample of non-victims.

The survey included a stalking questionnaire that listed 18 possible harassing behaviours, such as unwanted communications by letters, e-mails, faxes or telephone calls; following or loitering nearby, or invading the victim's home; damage to property; or sending unsolicited goods.

All participants were also asked to complete the World Health Organisation-5 Well-Being Index, which measures psychological health, as well as a questionnaire indicating difficulties in setting boundaries and distinguishing oneself from others (psychological dependency scale).

It was found that almost 12% of the respondents (68 women and 10 men) reported having been stalked. This represents a significantly higher rate among women (17%) than men (4%). Of the stalking victims, 87% were women, whereas 86% of the stalkers were men.

Nearly all the female victims (91%) were stalked by a man, but for male victims the proportion of male and female stalkers was about equal (44% male stalkers). This indicates that same-gender stalking is a significant problem in males. Women were identified as stalkers in only 14% of cases.

In line with previous findings, this study showed that stalking is mainly a product of some form of prior relationship: about 32% of the victims were pursued by previous intimate partners. Only 24.6% of stalking was done by strangers.

Victims in this study experienced an average of five different methods of intimidation, the most common being unwanted telephone calls and loitering nearby.

Victims also ran a high risk of being physically injured, with one third of cases experiencing assaults involving physical restraint, or beating or hitting with objects. Sexual pestering was also frequent, and almost one in five victims had experienced sexual assaults.

A high percentage of victims (73%) reported changes in lifestyle as a response to stalking behaviour. 56% reported agitation as a psychological symptom, 44% anxiety, 41% sleep disturbance, 35% nausea and 28% depression. Nearly a quarter sought help from a health professional in response to stalking.

Victims were found to have higher scores than non-victims on a psychological dependency scale.

The present study is the first to show the long-term impact of stalking. Having ever been a victim was associated with current psychological distress, even when a number of factors connected with psychological health were taken into account.

Mental-State Reasoning Is Universal Milestone in Child Development

Sun, 31 Jul 2005 14:06:00 PST

( from http://www.rxpgnews.com ) On this boring Wednesday afternoon, nothing would entertain a young child more than to play a joke on the babysitter. The sitter always keeps her lunch in her purse; so when she leaves the room, the little prankster quickly hides it under the couch. When the babysitter returns, where will she look first? Whether from Canada or Thailand, 3-year-old children will most likely guess under the couch; it will not be until the ripe old age of 5 that they know that the babysitter will look for her lunch right where she left it.

A major social-cognitive achievement of young children is the understanding that other people act on the basis of their own representations of reality rather than on the basis of reality itself. Developmental psychologists have explored the refinement of mental-state reasoning in children, typically by measuring their ability to pass false-belief tasks, such as the example above. Yet previous research has only been conducted in Western cultures, where children pass such tests around the age of 5. New research reveals that children reach this false-belief milestone at about the same age the world over.

The findings appear in the report, "Synchrony in the Onset of Mental-State Reasoning: Evidence from Five Cultures," published in the May 2005 issue of Psychological Science, a journal of the American Psychological Society. Researchers Tara Callaghan, St. Francis Xavier University; Mary Louise Claux, Catholic University of Peru; Shoji Itakura, Kyoto University; Angeline Lillard, University of Virginia; Hal Odden, Emory University; Philippe Rochat, Emory University; Saraswati Singh, M.K.P. College; and Sombat Tapanya, Chiang Mai University, tested the false-belief understanding of children in Canada, India, Peru, Samoa, and Thailand.

The test group consisted of 267 children, approximately 50 from each country, ranging from 30 to 72 months in age. The false-belief task involved the following test: One experimenter hid a trinket such as a coin or a ring under one of three bowls. When the first experimenter left the room, the second one told the children they were going to play a joke, and hid the trinket under a different bowl. The children were then asked which bowl they thought the first experimenter would check when she returned. Children who pointed to the bowl that initially hid the trinket, as opposed to the trinket's new location, "passed" the test.

Results from all five countries revealed a shift from failure to success on this task between the ages of 3 and 5, revealing that it is a universal milestone in child development. "Synchrony in the age at which children of diverse cultures pass the false-belief task undermines the claim that particular cultural views, such as a Western concept of mind, profoundly influence this very basic aspect of early mental-state reasoning, and strengthens a claim of universality," the authors wrote.

Fathers more involved when paternity is established in the hospital

Fri, 22 Jul 2005 01:00:00 PST

( from http://www.rxpgnews.com ) A study published in the recent issue of Journal of Marriage and Family examines the effectiveness of in-hospital paternity establishment for babies born to unwed parents. The research shows that though establishing paternity at any time increases the amount of formal and informal child support and the amount of father-child visits, in-hospital establishment is associated with better outcomes.

Analysis of interviews conducted a year after the baby's birth with mothers who remained single showed that fathers, who were named in the hospital, are fifteen percentage points more likely to have seen their child in the past month. Those whose paternity was established outside of the hospital are only seven points more likely to visit than those who did not have their paternity established.

"These finds suggest that, even among nonresidential parents, in-hospital paternity establishment is associated with higher levels of father involvement than establishing paternity outside the hospital," authors Ronald Mincy, Irwin Garfinkel, and Lenna Nepomnyaschy state.

Using the Fragile Families and Child well-being survey, the authors find that establishment rates are high, at sixty-nine percent, and six out of seven are established in the hospital. In-hospital paternity establishment programs have been a federal requirement since 1993. They provide unmarried parents with information about the benefits of paternity and require hospitals to inform parents about the legal obligations that occur, e.g. child support, once paternity is established. These programs are a friendly way to aid non-traditional families.

"We believe that increasing fathers' involvement very early in the lives of their nonmarital children may prove to be beneficial for their children's long-term well-being, and we plan to examine these relationships in future work," the authors conclude.

Brain networks change according to cognitive task

Thu, 02 Jun 2005 16:10:00 PST

( from http://www.rxpgnews.com ) Using a newly released method to analyze functional magnetic resonance imaging (fMRI), Northwestern University researchers have demonstrated that the interconnections between different parts of the brain are dynamic and not static. This and other findings answer longstanding debates about how brain networks operate to solve different cognitive tasks. They are presented in the current (June 1) issue of the Journal of Neuroscience.

Equally important, the researchers discovered that the brain region that performed the integration of information shifted depending on the task their subjects performed. In this study, the subjects were assigned two language tasks. In both, subjects were asked to read individual words and then make a spelling or rhyming judgment.

"We found that one network takes different configurations depending on the goal of the task," said Tali Bitan, primary author of "Shifts of Effective Connectivity Within a Language Network during Rhyming and Spelling."

A post-doctoral fellow in the department of communication sciences and disorders, Bitan worked with Associate Professor James Booth of the same department and M-Marsel Mesulam, director of the Cognitive Neurology and Alzheimer's Disease Center in Northwestern's Feinberg School of Medicine.

Mesulam, who was among the first scientists to predict the existence of convergence zones within interconnected brain networks, said the study presents "the clearest and most convincing evidence to date" of the dynamics in effective connectivity.

To better understand dynamic effective connectivity, Mesulam compares the brain networks to a network of highways connecting different parts of a city. The highway is static. No matter how heavy the traffic load, it always has the same number of lanes. In the brain, there is a dynamic change that allows certain pathways to preferentially facilitate the demands of a given cognitive task. The brain highway in effect "adds lanes" to accommodate the requirements of the particular task.

Depending on the goal of the task -- whether subjects were asked to make an orthographic (spelling) judgment or a phonological (rhyming) judgment the Northwestern researchers found that different convergence zones in the network were involved in the task.

"The existence and the identity of convergence zones --areas in which information from multiple sources meets in the brain -- have been debated since they were proposed in the late 20th century," said Bitan. "Now, with new techniques to analyze brain imaging data, we can examine the specific role played by different brain regions in the network that are required for any cognitive task. These techniques examining effective connectivity enable us to learn how the brain changes its interconnectivity according to the task at hand."

The Northwestern researchers also propose to explain the role of each brain region as it interacts within a complex network to achieve a specific cognitive goal.

The conventional method for analyzing fMRI data, which can only show which brain regions are active in a given task, showed two brain regions that were specifically active for each of the studied tasks: the lateral temporal cortex (LTC) for the rhyming task and the intraparietal sulcus (IPS) for the spelling task.

In addition to the task-specific regions, the inferior frontal gyrus (IFG) and the fusiform gyrus (FG) were engaged by both tasks. Dynamic Causal Modeling, the new method examining the influences between brain regions, indicates that each task preferentially strengthened the influences converging on the task specific regions (LTC for rhyming, IPS for spelling). This finding suggests that task specific regions serve as convergence zones that integrate information from other parts of the brain.

The results also show that switching between tasks -- in this case between rhyming and spelling -- led to changes in the influence of the IFG on the task specific regions. This finding suggests the IFG plays a pivotal role in "making" task specific regions more or less sensitive, depending on the task.

"Previous studies showed that the IFG is active in many different language tasks and suggested that the IFG was involved not only in the integration process but also in control of other brain regions," Bitan said. "Our study corroborates the role of the IFG in modulating other brain regions. In contrast, however, it shows that the integration process is done primarily in the task-specific regions."

In the 19th and early 20th century, scientists with a "localizationist" approach postulated that discrete brain regions were associated with specific functions of language and memory. By the end of the 20th century, a "connectionist" view stressing the importance of interconnected networks became the consensus.

The research presented in the Journal of Neuroscience effectively sets the stage for further development in our understanding of neuroscience. In their article, the Northwestern scientists provide evidence of the ways in which different cognitive goals are achieved from the interaction between different brain regions.

Human brain can learn without thinking - Research

Fri, 27 May 2005 18:27:00 PST

( from http://www.rxpgnews.com ) In this latest research, Watanabe and his team uncovered the mechanism that primes the subconscious, enabling individuals to learn a task without actually realizing it. They also showed this type of learning is retained, giving a new interpretation to how long a learned behavior is retained in the visual cortex -- an area of the brain thought to be fixed very early in life.

To establish how the mechanism worked, Watanabe's team devised a series of perception tests. Initially, participants watched a computer screen as a series of letters flashed by and were instructed to signal when they saw a gray letter. As individuals concentrated on watching for gray letters, sets of dots jiggled on the screen in areas that were at the periphery of the visual field. Five to 10 percent of the dots moved together in a coherent direction -- a fraction smaller than that easily detectible by the human eye. Letters flashing on the screen were randomly paired with the moving dots.

From this test, the researchers established the length of time it took each participant to identify the direction and coherent movement of the dots on the screen.

Participants were next exposed to a similar set of computer screens, this time with the fraction of the moving dots faded to just below the level of human perception. As participants watched for gray letters to appear in the center of the screen, the imperceptible dots moved coherently just outside their field of vision. Participants were exposed again and again to the imperceptible, moving dots as they signaled the gray letters and were later tested to see if their recognition time had improved.

In a subsequent round of tests, participants showed marked improvement in the time they took to recognize the coherently moving dots. Watanabe says this improvement demonstrates the participants learned to recognize and better identify the movement during the trials, even though their attention was focused somewhere else and the moving dots were faded to the point of being imperceptible.

The experiment differed from previous studies in having participants focus on something other than the moving dots -- in this case, the letters on the screen -- while being exposed to the movement of the imperceptible dots. Watanabe says that having subjects focus on letters activated an internal "reward" pathway in their brains, priming their subconscious to learn more efficiently.

According to Watanabe, the visual cortex, the area of the brain tested in his experiments, has long been considered unchangeable in humans past 6 months of age. Watanabe found it could be "changed" and that the changes could last for a considerable period; individuals were tested again six months after the initial trials and show little or no deterioration in their ability to recognize moving dots in a visually noisy background.

"It's possible that other parts of the brain could work this way too," Watanabe says. "People might be able to improve their pronunciation of a new language, if it's presented simply, without paying attention. It's possible the brain could be changed without a lot of effort."

The Watanabe group plans to repeat their experiments using functional magnetic resonance imaging, or fMRI, to peer into the brains of participants. Using fMRI, the team will essentially be able to look directly into the portion of the brain involved in subliminal learning.

Deadlines intensify emotions - Study

Thu, 26 May 2005 19:18:00 PST

( from http://www.rxpgnews.com ) Half of the scenarios included an explicit "limited-future" condition, such as the last day of a holiday. The other half differed only in that they made no mention of the future at all. The subjects, whose mean age was 20.68 years, were asked to read the scenarios and then indicate how intensely (on a scale of 1 to 5) they would experience 31 different emotions.

"Given time limits, people showed more extreme emotions on both the positive and negative ends of the scale," Teuscher said. "The test results suggest that a different time perspective itself can cause differences in emotional complexity and intensity."

In one experimental scenario, for example, half the participants were asked to picture an evening spent at a close colleague's home. The colleague is a very bad cook and burns the dinner. A dessert made and brought by the participant is not much better: It's dry and not at all what was planned. Nonetheless, the two have "a cheerful evening and chat until late into the night." The other half of the participants considered the same story in light of additional information that they would be retiring next week and moving to another city. Compared to the open-ended group, the time-limited subjects reported for this scenario that they would feel more closeness, more patience, more respect, more sadness and less irritation.

The findings, presented at the American Psychological Society annual convention in Los Angeles, May 26-29, may have broad implications, Teuscher said, "in the study of how people cope with endings and transitions, not only death but also separations, migration, job changes or retirement in short, any critical life event requiring people to deal with the foreseeable end of a situation."

Teuscher is also conducting research to see how a time-limited perspective affects decisions: Do people choose something different if they think they're choosing for the last time?

In an experiment involving book and movie selections, young subjects faced with a hypothetical limit on the future tended to go for familiar materials over reading or seeing something new. In other words, they made choices similar to those made by older individuals (as observed by other researchers).

"The salience of an approaching ending is a potentially powerful variable that has so far received little attention," Teuscher said. "It would be worthy of further investigation both in the fields of life-span development and decision-making."

Effect of Trait Self-Objectification on Body Shame

Thu, 26 May 2005 19:16:00 PST

( from http://www.rxpgnews.com ) Everywhere we look, we are bombarded by the media telling us how we should look and it affects our body image. Even cartoon characters are drawn a certain way, often sending an unrealistic message -- especially to women -- about the way they are supposed to look. It's enough to cause some women to suffer from anxiety, depression and to be ashamed of their bodies.

According to research done by a recent Kansas State University master's degree graduate in social psychology, a compliment can go a long way in easing a woman's anxiety over her looks. Courtney Fea said a kind word can reduce a woman's shame about her body if she looks at herself negatively.

"What we found was that for women who look at themselves as bodies, if you compliment them, they do feel better about themselves," Fea said. "And it doesn't matter what kind of compliment you give them; it doesn't matter if you compliment them about how they physically look or about who they are as a person."

Fea will present a paper based on her research, "Effect of Trait Self-Objectification on Body Shame, Appearance Anxiety and Unipolar Depression" at the American Psychological Society's convention May 27 in Los Angeles.

"It's a really exciting opportunity," Fea said. "It's nice to be able to present at a big, prestigious conference like this, and to be able to present on such a new and novel topic."

Although self-objectification has been discovered in girls as young as 4-5 years old, Fea's research focused on older subjects who often voice concerns like "my arms are too flabby" or "my hips are too wide."

"It's those things that they indicate the most embarrassment about," Fea said. "We used college students because not only is it a convenient sample, but it seems to be in the midst of the early 20s that the body anxiety and appearance shame is really observable and really well defined."

Fea would like to use the study to develop awareness that such a small thing like a compliment can do so much for boosting a woman's confidence and reduce their likelihood to experience depression about their body.

"Anyone can offer a compliment and it's really simple to do," Fea said. "In our case we only gave people one compliment and that was enough. So you can imagine if people are aware, like parents who are raising their daughter, they know 'wow, if I just give them one compliment,' that she's less likely to feel depressed or experience anxiety. Imagine what it would be like if parents gave their child or teenager compliments frequently."

Although all her research has been involved in women's issues, Fea admits she stumbled upon the topic. She hopes to eventually earn a doctorate degree in this area and would like to further her research by examining what the effect would be if giving people one compliment, which Fea did in her research, versus several compliments, would have a larger effect.

"The area isn't new but the way of studying it is new," Fea said. "People are just starting to put the pieces together. They knew beforehand that women got depressed and women had body shame but now they're really trying to figure out how to stop this."

Fea acknowledges that there is a fine line between a compliment and harassment, with that dividing line being determined by the recipient of the compliment. She emphasized that the compliments, do not have to be based on a woman's appearance. Fea hopes that based on this research, people take into greater consideration how they talk to each other.

"I hope they keep in mind we can have a great impact on those around us," Fea said. "I hope the impact will be for the better and not for the worse."

Childrens fears learned through observation

Mon, 11 Apr 2005 12:33:00 PST

( from http://www.rxpgnews.com ) Psychologists have found evidence which suggests that children can learn to be fearful of something just by observing another's facial expressions.

The study, which aimed to investigate whether children's fear beliefs about a picture of a previously un-encountered animal increased after seeing it together with scared faces, was conducted using a group of 8-9 year olds. Each child was presented with pictures of two Australian marsupials together with either fearful or happy faces. A third animal was also presented, this was not paired with any faces. Fear beliefs about each animal were measured by self-report questionnaires both before and after the viewing the pictures.

The study, which was repeated one week later, found that fear beliefs increased for animals paired with fearful faces and decreased for animals paired with happy faces, compared to the non-paired animal. Significant differences in fear beliefs and attitudes were still present one week later.

Mr Askew said: "Seeing imaginary animals together with fearful faces appears to increase children's fear beliefs and negative attitudes toward the animal. Thus the results show how children's fear beliefs about a previously unknown stimulus can be affected just by observing another's facial expressions. The findings therefore will have implications for both the theory and treatment of fears".

It aint what you say - its the way that you say it

Mon, 11 Apr 2005 12:33:00 PST

( from http://www.rxpgnews.com ) People who are confident about what they are saying are more likely to persuade others of their point of view confirm psychologists.

Using an experiment involving participants who had to look at nine photographs of faces then work with each other to agree which e-fit type picture showed the best likeness, the researchers confirmed a theory originally proposed in 1995. This stated that when people communicate beliefs to one another they express degrees of confidence proportional to the certainty with which they hold those beliefs. Furthermore the people being communicated to tend to judge the reliability of the information they are being given according to the confidence with which it is expressed.

Fifty six participants worked in pairs with one participant being shown a good e-fit likeness of one of the faces in the set of nine photographs they were given designed to induce high confidence and accuracy of identification. The other partner was given a weak e-fit with a poor resemblance of one or more of the other faces. Participants were not shown each other's e-fits but were allowed time to discuss which face from the set of photographs they wanted to choose as the suspected criminal. When they both chose the right face they were rewarded with 40p, when they both agreed on a face but it was the wrong one they received just 20p. If they chose different faces they received no reward.

The number of times the person with the strong evidence persuaded the other to agree on the correct face was significantly higher than the number of times the person with the weaker e-fit persuaded the other to choose the incorrect face.

Dr Briony Pulford said: "What we have been able to do is experimentally support the theory of Thomas and McFadyen that confident communicators are more persuasive, but we think there may still be much to learn about this process and what other factors might have a bearing. Never the less, it should make us aware that those people who are the most persuasive are likely to be those who have the highest certainty in what they are saying."

Different styles of mother-infant interaction affect different aspects of infant cognition

Fri, 08 Apr 2005 04:16:00 PST

( from http://www.rxpgnews.com ) Although the quality of mother-child interaction and its effect on general IQ and later schooling is a widely researched topic, it has never been studied using the same infants over a period of time across several cognitive domains.

The research, funded by Pampers of Procter and Gamble, examined some 200 infants who, along with their mothers, visited the labs for one half day when the infants were six months old and for another half-day at ten months old. To ensure a large database, three European labs (London, Paris, Munich), set up identically to the greatest extent possible, tested each of their infants across all the cognitive domains and recorded mother-infant interaction at both ages.

The symposium will begin with a paper presented by Professor Annette Karmiloff-Smith from the Institute of Child Health in London, who will set the scene for the remaining three research papers. These will begin with a paper on action perception research, in which Dr Annette Hohenberger, from the Institute for Human Cognitive and Brain Sciences, Munich, will talk about the results from the three labs on infant perception of goal-directed actions and causal events between objects, in relation to mother-infant interaction.

Following this, a third paper will examine the results of the speech processing experiments, in which each infant participated in two syllable discrimination experiments, one in their native language (English, French or German) and one from a different language family, namely Hindi. Ms Mayada Elsabbagh, of the Institute of Child Health in London, will discuss how discrimination of native and non-native language contrasts relate to mother-infant interaction.

The final research paper, presented by Professor de Schonen, of the Centre for National Scientific Research, Paris, will discuss the results of the face processing tasks, which were based on the hypothesis that infants can initially discriminate faces from all ethnic groups but subsequently specialise in the faces of their own ethnic group. Professor de Schonen will examine whether changes in face processing occur at the same time as changes in speech processing or at different times. The symposium will conclude with a discussion from an expert in infant studies, Dr. Gaia Scerif, from the University of Nottingham.

Symposium convenor, Professor Annette Karmiloff-Smith from the Institute for Child Health, said: "This very ambitious study involving three European labs, examining several cognitive domains within the same infants longitudinally, is yielding exciting new results about different influences on infant development."

Juggling the finances is source of student stress

Fri, 08 Apr 2005 04:16:00 PST

( from http://www.rxpgnews.com ) The pressure of money problems is leading to increased rates of depression, anxiety and stress amongst university students. But, it is not the amount they owe that causes students to become depressed, anxious and stressed; it is whether or not they can manage their finances on a daily basis.

Dr Scott questioned 268 students about the size of their student debt, how manageable that debt felt to them, and whether or not they had financial problems in their day-to-day living. He found that although the amount students owed was not related to depression, anxiety or stress, money problems on a day-to-day basis were.

According to Dr Scott: "Often the amount of money students can borrow is not enough for their daily needs, and the resulting financial difficulties may lead to depression, anxiety and stress. Although the overall size of students' debt is clearly important after graduation; at university, it is whether or not that debt impacts upon their daily existence that really matters."

"This research shows," continued Dr Scott, "the importance of providing training in money management for students attending university, and the need for universities to provide early support for students experiencing money problems."

Worrying about Maths just makes it worse

Fri, 08 Apr 2005 04:16:00 PST

( from http://www.rxpgnews.com ) People who worry about their ability to do mathematics are hampering their chances of doing well. Worrying about mathematics means that vital psychological resources are used which impacts on an individual's ability to solve arithmetic problems.

These are the findings of Dr Sheila Ford and her team of psychologists at Staffordshire University which are presented at the British Psychological Society's Annual Conference at the University of Manchester on Saturday 2 April 2005.

Dr Ford and her colleagues asked 52 participants to complete 180 problems displayed on a computer screen. These problems were a combination of mathematical tasks, letter recall tasks and tasks which required participants to recall letters and do maths simultaneously. Prior to completing the problems each participant completed an inventory which assessed how anxious they felt about completing mathematical tasks.

Participants with high levels of maths anxiety were less accurate and made larger errors on the mathematical tasks. One particularly interesting finding was that these highly anxious participants were also poorer at remembering the serial order of letters, but only when they were performing a concurrent maths task.

Dr Ford said: "It appears that maths anxiety affects performance on arithmetical problems because anxious intrusive thoughts compete for limited memory resources and this may disrupt the calculation processes involved in arithmetic problem solving."

Fighting appears to provide professional fighters with a forum to enrich their friendships

Fri, 08 Apr 2005 04:16:00 PST

( from http://www.rxpgnews.com ) Contrary to stereotypes, fighting appears to provide professional fighters with a forum in which to establish, strengthen and enrich their friendships.

This is the conclusion of Dr Martin Milton at the University of Surrey who will present his findings at the British Psychological Society's Annual Conference at the University of Manchester on Saturday 2 April 2005.

Dr Milton spoke to professional fighters in sports such as mixed-martial arts and boxing who competed in the UK and abroad. He questioned the group on how they managed their relationships with fellow fighters and other people who played a significant role in their lives.

He found they experienced fighting as a way in which they initiated and deepened friendships and the fighters identified a sense of camaraderie and bonding as important factors in this process.

The enriching of friendships seemed to proceed through a specific relational process - which was initially to see their opponent either as a 'non-entity' or as someone on whom to focus their aggression. During the fight their attention was completely on the opponent and it seems that this process often led to a respect and appreciation of the opponent - so much so that strong friendships develop.

Dr Milton said "The research suggests that although fighting is often demonised, there are ways in which it seems to facilitate respect and deepen relationships between the participants. This shows that not only are fighters able to turn their aggression on and off but that fighters are alert to relational factors and attend to other people, both within the cage or ring and outside of it. This has implications for how we perceive fighters - both inside and outside of the consulting room."

However Dr Milton added that the significant time that fighters have to dedicate to their training means there is less time available to invest in romantic relationships. This and the concern that partners have for the physical well-being of the fighter means that strain is placed on those relationships.

Psychological stress in overseas aid workers

Fri, 08 Apr 2005 04:16:00 PST

( from http://www.rxpgnews.com ) Aid agencies should provide psychological support for their staff "as a matter of course", says a psychologist who has studied the way traumatic events affect aid workers.

Dr Ashleigh Quaite from the University of Hertfordshire made this call at the Annual Conference of the Division of Clinical Psychology at the University of Manchester on Friday 1 April 2005.

Dr Quaite asked 42 overseas aid workers to complete questionnaires about their experience in the field and their reactions to it. He found that 59.5 per cent had experienced one traumatic event in their work and that 26.2 per cent had experienced more than five. Even more (78.4 per cent) had experienced a traumatic event indirectly, for instance by hearing someone else's account of an incident or seeing photographic images.

Taken together, the figures showed that 97.6 per cent of the sample had experienced directly or indirectly one of 17 recognised traumatic events. Of this sample, 88.0 per cent reported suffering the effects of trauma to some degree, with 40.5 per cent likely to meet the clinical criteria for Post-Traumatic Stress Disorder (PTSD). Workers who were suffering from PTSD were also more likely than other workers to suffer from vicarious traumatisation and job burnout.

Dr Quaite says: "There has been so little research done that I doubt if anyone knows how much support overseas aid workers receive, but I have heard anecdotal reports from experienced workers about a general lack of provision. If these findings are typical of aid workers as a whole, then agencies should provide psychological support to their workers as a matter of course."

Dr Quaite is now comparing the thought processes of workers who do and do not experience problems after witnessing traumatic events to see how people can be helped to cope with distressing experiences.

Control key to self examination

Fri, 08 Apr 2005 04:16:00 PST

( from http://www.rxpgnews.com ) Whether people carry out self examination for health conditions is related to how much control they feel over their health. New research by psychologists suggests that for both men and women, their anxiety about a condition and feelings of control over their health may predict the likelihood of carrying out self-examination.

The research by Penelope List from Keele University, will be presented at the British Psychological Society's Annual Conference at the University of Manchester on Friday 1 April 2005.

In a series of studies, Penelope List and her colleagues, Martin Johnson of the University of Newcastle, Australia and Sarah Baker of Sheffield University used questionnaires to explore what determines whether people will carry out self-examination for cancerous conditions. Men and women, ranging in age from 21 to 86 years, were asked about their knowledge of the need for self-examination and their actual frequency of examination.

The studies measured people's general anxiety and specific anxiety about particular forms of cancer, as well as how much they felt they were in control of their health.

The studies' findings reinforce the generally held view that women are more aware of the need for self examination and that it should be done regularly. The women in the study were also more anxious about breast cancer than bowel cancer.

The men were less anxious overall about the dangers of testicular cancer or bowel cancer and less aware of the need for examination. However, the men who carried out self-examination were likely to be more anxious about testicular cancer than those who did not. The study also found that people who felt that they had more control over their health carry out more frequent and more regular examinations.

The findings of the studies illustrate how health messages need to continue to stress the value of self checking for a range of health conditions including cancer, which benefit from early detection. This is particularly so for those who might see themselves as least at risk, for example young men.

Different paths lead to similar Cognitive Abilities

Wed, 06 Apr 2005 19:11:00 PST

( from http://www.rxpgnews.com ) Despite the divergent evolutionary paths of dolphins and primates -- and their vastly different brains -- both have developed similar high-level cognitive abilities, says Emory University neuroscientist and behavioral biologist Lori Marino. She presented her latest findings on the evolution of and differences in brain structure between cetaceans (ocean mammals like whales and dolphins) and primates April 5 during the 14th annual Experimental Biology 2005 meeting in San Diego.

Marino's presentation examined the diverse evolutionary patterns through which dolphins and primates acquired their large brains, how those brains differ, and how sensory information can be processed in different ways and still result in the same cognitive abilities.

"Eventually, a better understanding of how other species process information might be useful in helping people impaired in "human" ways of processing information. Perhaps there are alternative ways to sort out information in our own brains," says Marino, whose talk was part of the scientific sessions of the American Association of Anatomists.

Recent research by Marino and her colleagues has traced the changing encephalization, or relative brain size, of cetaceans during the past 47 million years by using magnetic resonance imaging and histological studies of the fossil record. While modern humans have brains that are seven times bigger than would be expected for our body size, giving us an encephalization level of seven, some modern dolphins and whales have an encephalization level close to five -- not a huge difference, says Marino. For example, Homo sapiens' closest relatives, the great apes, have encephalization levels of only two to two-and-a-half.

"While humans are the most encephalized -- the brainiest -- creatures on earth, we are relative newcomers to that status," says Marino. "The cetaceans enjoyed a tremendous increase in brain size and organization about 35 million years ago, whereas humans got their big brains much more recently during the past one to two million years."

Marino's earlier research has shown how dolphins have the capacity for mirror self-recognition, a feat of intelligence previously thought to be reserved only for Homo sapiens and their closest primate cousins. Marino is a professor of neuroscience and behavioral biology at Emory and a research associate at the Yerkes National Primate Research Center. Her work has been funded by the National Science Foundation, The SETI Institute, The Smithsonian Institution, and Emory University.

New Research into Human Ability to recognize Faces

Tue, 05 Apr 2005 17:39:00 PST

( from http://www.rxpgnews.com ) Recognizing faces is effortless for most people, and it's an ability that provides great evolutionary and social advantages. But this ability is impaired in people who have suffered brain damage or in those with a rare congenital condition, and research by Carnegie Mellon University psychologists reveals startling insights into how the brains of those individuals operate. Psychology Professor Marlene Behrmann and postdoctoral associate Galia Avidan have found that people with congenital prosopagnosia--in which their ability to recognize faces is impaired from birth--are not just deficient at recognizing individuals they know, but they are also poor at simply discriminating between two faces when presented side by side. The researchers also have discovered through functional Magnetic Resonance Imaging (fMRI) scans that, contrary to their expectations, the regions of the brain that are activated when normal individuals perceive and recognize faces also are activated in individuals with congenital prosopagnosia (CP).

"This now presents a large scientific challenge. Given that the impaired behavior in those individuals with prosopagnosia is a function of the brain, we need to identify the neural system that has given rise to this altered pattern of behavior," Behrmann said. "The detective work is well under way."

Unlike the acquired form of prosopagnosia--which results from brain damage such as that suffered in a stroke--congenital prosopagnosia can go undetected, as the person has no means of comparison with normal face processing skills. This can have socially debilitating consequences, and on occasion children with this condition have been misdiagnosed as having autism.

"The potential ramifications of CP are best captured in the words of one individual whom we have had the opportunity to test: 'I have always been a rather extreme introvert, uncomfortable in groups of people and in social activities. I sort of tend to want to be a hermit. However, I find it relaxing to go window-shopping in a mall. A crowd of a hundred strangers is more relaxing than a dozen neighbors whom I know,'" Behrmann said.

Behrmann and Galia said that much remains to be learned from the individuals in their research. They have begun to examine the anatomical details of the brains of their participants, and preliminary findings show that some brain structures are smaller in the region known to control face recognition. Congenital prosopagnosia seems to run in families, which suggests a genetic basis, although that is not true in every case and Behrmann cautioned against calling the condition a genetic disorder. Unfortunately, a cure for the disorder is unlikely to be found anytime soon.

"The work on CP is in its infancy and we still need to understand the psychological and neural aspects of the disorder in detail. It is possible, however, that some forms of intervention may become possible in the near future," Behrmann said.

Eye Training Can Improve Performance for Radiologists

Fri, 01 Apr 2005 16:50:00 PST

( from http://www.rxpgnews.com ) A new study suggests there may be a better way to sharpen the eyes of radiologists, military pilots and other professionals for whom identifying objects or patterns in a monitor or visual display often quickly and with pinpoint accuracy is a critical part of the job.

According to the study, the new approach involves rethinking how the eyes are trained to filter out clutter and focus in on a target. Previously, scientists believed these two perceptual skills intermixed and worked simultaneously. This study, however, demonstrates that they are in fact independent and best practiced in a specific order.

The study, by UCI cognitive scientist Barbara Anne Dosher and USC colleague Zhong-Lin Lu, is published in this weeks Proceedings of the National Academy of Sciences.

This research demonstrates, for the first time, the independence of these two learning mechanisms, and suggests new methods of training for people who must pinpoint targets in busy images, Dosher said.

The researchers tested six volunteers with normal vision. Half of the volunteers trained first on clear, or low-clutter, displays, identifying targets or patterns ranging from dim to strong using the amplification or focusing in process. Then they trained on noisy, or high-clutter, displays, exercising their filtering mechanism. The other three volunteers started with the noisy displays and then switched to clear. Over five days, the volunteers made nearly 4,000 practice judgments in each condition, with accuracy measured every 180 trials.

The researchers found that those who first trained on the clear displays approximately doubled their efficiency and transferred their improved performance to the cluttered displays immediately. Those that first trained on the cluttered displays did not show any transferred improvement when they tested on the clear displays.

We were surprised to find training the eyes in the one process would transfer so extensively to the other, but not vice versa, Dosher said.

Dosher and Lu have been working in visual attention and perceptual learning for nearly six years. In addition to shedding light on perceptual learning processes, their testing methods and models have been used to evaluate the processing limitation of people with visual deficits.

Police Officers' Racial Bias Can Be Eliminated

Fri, 01 Apr 2005 16:34:00 PST

( from http://www.rxpgnews.com ) On March 15, 2003 in Shreveport, Louisiana, a 25-year-old black man was shot to death by police who mistook the cell phone he was carrying for a weapon. No one can be certain whether race was a factor in the tragic death, but previous research shows that people's expectations about whether another person is holding a weapon are influenced by that person's race. New research in the March issue of Psychological Science, a journal of the American Psychological Society, shows that extensive training with a computer simulation can eliminate this racial bias.

Authors E. Ashby Plant and B. Michelle Peruche, both of Florida State University, studied 50 police officers from Florida using a computer simulation in which a gun or a neutral object (a wallet or a cell phone) was superimposed onto a white or black face. The police officers then had to choose to shoot or not to shoot by pressing a designated key.

The earlier trials revealed that the officers were more likely to mistakenly shoot at an unarmed black suspect than at an unarmed white suspect. "However, on a more promising note, after extensive exposure to the program, the officers were able to eliminate this bias," the authors state. In later trials, officers were more accurate in their decisions to fire at suspects of either race due to their more accurate detection of weapons.

The authors stated, "These findings have important implications for both the elimination of racial biases in general and the training of police officers more specifically." The authors suggest future work to test whether elimination of racial bias on the computer simulation generalizes to actual decision making in the field. If so, "training on such simulations may provide an important tool for improving overall accuracy in police officers' decisions to shoot."

Potentially Successful People are the Most Likely to Choke Under Pressure

Tue, 01 Mar 2005 16:34:00 PST

( from http://www.rxpgnews.com ) Have you ever studied hard for an important test, gone in prepared, and just somehow bombed anyway? You might have said to yourself, "I just choked under the pressure." New research in the February issue of Psychological Science, a journal of the American Psychological Society, shows that, at least for some people, there may be a lot to that excuse. People high in working memory capacity a strong indicator of brainpower may lose their cognitive advantages in high-pressure tasks like taking tests.

Working memory is a short-term memory system that holds information that has immediate relevance to a task and keeps you focused on it. A persons working memory capacity is known to predict how well they do at comprehension and learning, and, under normal conditions, how well they perform on difficult tasks. But according to the new study, it might not predict how well they do under pressure.

Normally, people with high working memory capacity (or HWM) have more cognitive "resources" available for problem-solving than do people with low working memory capacity (or LWM). However, the authors of the new report, Sian L. Beilock, Miami University of Ohio, and Thomas H. Carr, Michigan State University, were surprised to find that, when placed in high-pressure situations, "only individuals high in working memory capacity showed decrements" in performance. Participants solved novel math problems of varying difficulties in both high- and low-pressure situations. The LWM individuals' performance, in contrast, did not deviate between situations.

How can these results be explained? The authors hypothesize that the extra cognitive resources and attentional capacity in the HWM participants were consumed by pressure-induced anxiety, resulting in working memory capacity similar to those with LWM.

This research has relevance in education, among other things. For instance, it raises questions about how well high-pressure tests like the SAT and college entrance exams can really predict who is most likely to succeed in future academic endeavors.

Mismatched Messages Improve Mathematics Instruction

Thu, 17 Feb 2005 16:34:00 PST

( from http://www.rxpgnews.com ) Researchers at the University of Chicago have come up with a technique for teachers to use that increases student understanding of mathematics: explain how to solve a problem in one way, and also provide an alternative approach through gesture.

Students who were taught to solve arithmetic problems by teachers using mismatched gesture and speech learned twice as well as students who received instruction in speech only. The technique also helped students learn better than students who received instruction that was the same in speech and gesture, the researchers report in an article, "Children Learn When Their Teachers Gestures and Speech Differ," published in the current issue of Psychological Science.

"Teachers gesture when they teach, and those gestures do not always convey the same information as the speech they accompany," writes Susan Goldin-Meadow, the Irving B. Harris Professor in Psychology at the University and co-author of the study. "Gesture thus offers students a second approach to the problem at hand," said Goldin-Meadow, who co-wrote the article with Melissa Singer, a 2004 PhD graduate of the University of Chicago, and now a researcher at the University of Illinois at Chicago.

"Our findings make it clear that children can take advantage of the offerchildren profit from gesture when it conveys information that differs from the information conveyed in speech," Goldin-Meadow noted.

Goldin-Meadow said a mismatching gesture provides an additional explanation and is effective because it visually illustrates another way to solve the problem being explained. Teachers often use mismatching gestures with their speech spontaneously without realizing it, she said.

For the study, researchers tested 160 students who were finishing third grade or beginning fourth grade in Chicago public and parochial schools. The students were given arithmetic problems to solve and then were asked to explain their solutions at a chalkboard.

The students were taught to find a missing number in an equation with two separate approaches. For example, the problem 6 + 4 + 3 = __ + 3 can be solved in two ways: either by following the algorithm "add up the numbers on the left side of the equation and subtract the number on the right," or by following the principle "both sides of the equation must add up to the same number."

This is how the mismatched gesture-and-speech lesson worked:

A child was given the equation and the teacher explained the equalizing principle by saying both sides need to have the same numerical value. But at the same time, the teacher pointed at the 6, 4 and 3 on the left side of the equation and then produced a "flick away" subtract gesture under the 3 on the right side of the equation, which signaled the "add-subtract" algorithm.

In addition to teaching with mismatched gestures and speech, teachers also instructed students in the two problem-solving approaches verbally and by using matching gestures and speech.

"Surprisingly, teaching children two problem-solving strategies in speech was significantly worse than teaching one strategy, suggesting that children may have been overwhelmed by the additional spoken strategy," write Goldin-Meadow and Singer. For example, on average, students taught through two verbal explanations without gesture answered one out of six problems correctly. Children who learned the two problem-solving strategies with mismatched gestures and speech solved three out of six problems correctly.

Goldin-Meadows work also has shown that gesture helps make learning easier because it relieves some of the mental effort students expend in processing spoken lessons.

"Given previous work establishing the breadth and depth of gesture production across many tasks and ages, these data open the possibility of a heretofore unappreciated technique to improve learning in and out of the classroom," Goldin-Meadow writes.

RxPG News : Psychology

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Psychiatrist warns about impact of social networking sites

Study shows how context dictates what we believe we see

Loneliness could be bad for health

Do I know you? QBI researchers identify woman's struggle to recognize new faces

STAMP system can help medical professionals to predict violence

New Insights Into the Nature of Pride as a Social Function

Girls Select Partners Who Resemble Their Dads - Research

The benefits of social contact

Mapping attention, memory and language links in human brain

Gender and Income Does Determine Cognitive Function

Sex Differences are also Reflected in Brain

Abstinence Education Does Not Impact Sexual Behavior

School bullying affects majority of elementary students

Virtual racing seems to lead to aggressive driving

Emotional responses usually take over rational responses in decision making

Cell phone tunes could reflect one's personality

Touch tracking bypasses mind control

Making the connection between a sound and a reward changes behavioral response

Irrational decisions driven by emotions

Mice learn set shifting tasks to help treat human psychiatric disorders

How behaviors can be changed or created

People more likely to help others they think are 'like them'

Avoiding Punishment Is Its Own Reward

Does psychological treatment for adult sex offenders work?

How people behave differently when they are being watched

Broca's area also organizes behavioral hierarchies

Erotic images elicit strong response from brain

Men infer sexual interest before women do

What do football and alcohol have to do with being a man?

Prosopagnosia may affect 2 percent of population

Nerve cells in brain decide between apples and oranges

How Visual Stimulation Turns Up Bdnf Genes to Shape the Brain

Humans perceive more than they think they do

Specific Mechanisms May Not Exist For Facial Recognition

Scent of fear impacts cognitive performance

Older people with stronger cognitive skills walk at a safer pace

Switch for brain's pleasure pathway found

'Executive' monkeys influenced by other executives, not subordinates

Manipulating Cell Receptor Alters Animal Behavior

Morphine addiction and the tendency to explore linked

New study shows how self-prophecies may help

Guilt and fear motivate better than hope

How the brain makes a whole out of parts

Link in brain between sight and sound perception

The cognitive cost of being a twin

Researchers Identified Fear Factor Protein

Loneliness might be Explained by Genes

We do not feel with our sensory cortices

Choice Blindness Experiment Sheds More Light On Decision Making Processes

The maternal instinct for commitment

Link between body and action perception revealed

Women tend to model relationship behavior of their mothers

Expectations have a surprisingly big effect on pain intensity

Factors influencing preschoolers perceptions about cigarettes and alcohol

Male and female voices affect brain differently

Mixed results from abstinence-only intervention

Psychological and behavioural reactions to the bombings in London on 7 July 2005

Investigating the controversy about whether bisexual men exist

Different event-related potentials (ERPs) to pictures and words that describe the same object

Financially richer people tend to be happier - Study

Prenatal alcohol exposure can lead to slower cognitive reaction times and poorer attention

The effort required to correctly hear and identify words may diminish the resources needed to memorize them

Hand Movements Suggest Continuous Language Processing

Significant long-term impact of stalking found on victims' psychological health

Mental-State Reasoning Is Universal Milestone in Child Development

Fathers more involved when paternity is established in the hospital

Brain networks change according to cognitive task

Human brain can learn without thinking - Research

Deadlines intensify emotions - Study

Effect of Trait Self-Objectification on Body Shame

Childrens fears learned through observation

It aint what you say - its the way that you say it

Different styles of mother-infant interaction affect different aspects of infant cognition

Juggling the finances is source of student stress

Childrens fears learned through observation

It aint what you say - its the way that you say it