Can’t stick to a diet? Your brain wiring may be to blame, say scientists who found that the ability to self-regulate body weight may depend on a person’s brain structure.Obesity and dieting are increasingly common in contemporary society, and many dieters struggle to lose excess weight, researchers said.
After studying the connections between the executive control and reward systems in the brain, Pin-Hao Andy Chen from Dartmouth College in the US and colleagues showed that dieting success may be easier for some people.
This is so because they have an improved white matter pathway connecting the executive control and reward systems in their brain.
Chronic dieters are known to show excessive reactions to food cues in executive control and reward areas of the brain, in addition to having depleted cognitive control and over-rewarding with high calorie foods in real life situations.
Researchers took a group of thirty six chronic dieters, with mean body fat of 29.6 per cent, and asked them to make simple judgements on images in order to divert their attention from the real aim of the task.
The activity carried out was a food cue reactivity task designed to localise the executive control and reward areas in the brain, using functional magnetic resonance imaging (fMRI).
After localising the executive control and reward areas, researchers used diffusion tensor imaging (DTI) to identify the white matter track connecting these areas in order to quantify the integrity within this tract.
The fMRI results demonstrated that dieters showed greater reactivity to food images than control images. The DTI results further showed that those with lower body fat percentages showed greater white matter integrity between executive control and reward areas of the brain.
The findings support their hypothesis that structural integrity connecting the two centres relates to individual differences in body fat and is an indication of dieting success.
“Individuals with reduced integrity may have difficulty in overriding rewarding temptations, leading to a greater chance of becoming obese than those with higher structural integrity,” researchers said.
The study appears in the journal Cognitive Neuroscience.
