Reward deficits in compulsive eating

Food is consumed for at least two reasons: to maintain energy homeostasis and to obtain the pleasurable properties of palatable food items. Consumption driven by the hedonic properties of palatable food can result in excessive caloric intake, which likely plays an important role in the strikingly high rates of obesity in developed countries. Compared with the well-characterized mechanisms of homeostatic feeding, less is known about the mechanisms of hedonic feeding. Palatable food can stimulate activity in brain reward systems, and emerging evidence suggests that excessive consumption of such food items can trigger counteradaptive responses in reward circuitries similar to the actions of drugs of abuse. Here, I will summarize our current understanding of how overconsumption of palatable energy-dense food can alter the activity of brain reward systems and the role that such diet-induced reward dysfunction may play in the emergence of compulsive eating.