Dopamine-related frontostriatal abnormalities in obesity and binge-eating disorder: emerging evidence for...

Obesity and binge-eating disorder (BED) frequently arise in adolescence, which is a critical developmental time period where self-regulatory processes are formed. Indeed, both obesity and BED are thought to arise partly due to deficits in self-regulatory processes (i.e. lack of inhibitory control to overeat or binge). Recent neuroimaging studies have implicated the frontal cortex, a brain region involved in regulating inhibitory-control, and the striatum, which is thought to be involved in food reward, satiety and pleasure, in mediating responses to food cues and feeding in normal-weight individuals as well as obese and BED subjects. Intriguingly, frontostriatal circuits have been observed to be preferentially modulated in obese adults and similar associations have been observed in obese/overweight adolescents. Furthermore, brain dopamine (DA) is selectively altered in striatum in obese relative to normal-weight individuals, and frontostriatal regions constitute a major component of DA circuitry. The aim of this review will be to present the main findings from neuroimaging studies in obese and BED adults and adolescents, as these relate to frontostriatal circuitry, and to emphasize the potential for using functional neuroimaging in both humans and animals with the scope of obtaining information on developmental and molecular contributions to obesity and BED.