US researchers have mapped the areas of the brain associated with hunger and the sense of fullness known as satiation as a way to help understand weight gain, obesity and anorexia. Investigators from the National Institute of Diabetes and Digestive and Kidney Diseases studied the brains of 11 normal-weight volunteers using positron emission tomography, measuring regional blood flow which indicates which brain areas are active.
They describe their findings in the current Proceedings of the National Academy of Sciences. Hunger was linked to many areas including those known to be associated with emotions and motivation. Satiation was associated with areas linked to working memory and analytic reasoning and those which inhibit inappropriate behaviour.