This theoretical proposal presents a revised framework for the role of reward in anorexia nervosa (AN). AN is associated with a fear of weight gain and refusal to maintain a minimally normal body weight. Up to 80% of patients engage in excessive exercise, in addition to self-starvation, to reduce their body weight. Anhedonia is the reduced ability to experience reward and is considered a feature of AN. Reward has been linked to reduced food intake and excessive exercise. This proposal portends that whilst patients' pathological behaviors are in the first instance, rewarding, they become reinforced in a manner that becomes pathological, even punishing. Patients, however, may not recognize that they are contaminating aspects of reward with punishment, which may impair their ability to regulate their behaviors. Neural overlap between circuits that process reward and those that process punishment, is proposed as a mechanism in AN, in addition to which the anterior cingulate cortex, may represent a key locus for reward-contamination.