From rxpgnews.com

Obesity
New study shows some people just can’t resist food
By MRC Cognition and Brain Sciences Unit, Cambridge
Jun 2, 2006, 22:51

Scientists have discovered why some people’s brains are particularly vulnerable to food advertising and product packaging, putting them at risk of overeating and becoming overweight. The research provides fresh insight into one of the neurobiological factors underlying obesity by showing how some people are more attracted to the prospect of being rewarded with tasty food than others. The findings from a group of scientists at the Medical Research Council’s Cognition and Brain Sciences Unit in Cambridge led by Andy Calder and Andrew Lawrence are published in the Journal of Neuroscience.

Different people have higher or lower reward sensitivity, a personality trait that reflects a general desire to pursue rewarding or pleasurable experiences. The research shows that individuals with higher reward sensitivity, show increased activity in the parts of the brain implicated in motivation or reward when simply looking at pictures of appetizing food.

Previous research has shown that people with high reward sensitivity have stronger food cravings and are more likely to be overweight, but until now, the biological basis of this effect was unknown. This new research identifies how this relationship operates in the human brain, resulting in greater susceptibility to food advertising.

The study used the latest technology in brain imaging. The researchers showed people pictures of highly appetizing foods (e.g. chocolate cakes), bland foods (e.g. broccoli), and disgusting foods (e.g. rotten meat) while measuring brain activity using an fMRI scanner. After testing, the study participants completed a questionnaire that assessed their general desire to pursue rewarding items or goals. The results showed that the participant’s scores on the reward sensitivity questionnaire predicted the extent to which the appetizing food images activated their brain’s reward network.

“Previous studies in this area have assumed that brain activation patterns are similar in all healthy individuals. But the new findings demonstrate that even in healthy individuals some peoples’ brain reward centers are more sensitive to appetizing food cues. This helps explain why some individuals are more vulnerable to developing certain disorders like binge-eating,” said Dr John Beaver, lead author of the study.

“This is particularly pertinent in understanding the rapidly increasing prevalence of obesity, as people are constantly bombarded with images of appetizing food items in order to promote food intake through television advertising, vending machines, or product packaging.”

According to Dr Beaver the findings may also have broader implications for understanding vulnerability to multiple forms of addiction and compulsive behaviors.

“Research demonstrates that an individual’s reward sensitivity may also relate to their vulnerability to substance abuse, and the brain network we have identified is hyper-responsive to drug cues in addicts,” he said.

All rights reserved by www.rxpgnews.com