The common pathways of eating disorders and addiction: Exploring the link between reward/motivation, affect regulation and cognitive control

Eating disorders involve the inability to appropriately regulate a behavioral response to food due to impaired reward sensitivity, affect regulation and cognitive control, resulting in deleterious effects on the individual's physical and mental well-being. In this way eating disorders may be analogous to addictive disorders (e.g. alcoholism). Furthermore, eating and addictive disorders co-occur at very high rates and appear to have similar contributing mechanisms (impaired reward sensitivity, impaired affect regulation and impaired cognitive control). Overvaluation of weight and shape concerns appears to be one unique characteristic of eating disorders, not shared with addiction. The current study examined the relationship between impaired reward sensitivity, impaired affect regulation and impaired cognitive control with addiction vulnerability. Furthermore, weight and shape concerns were examined as a potential moderator of the relationship between addiction vulnerability and binge eating. A total of 1000 undergraduate students completed self-report measures examining the three posited mechanisms for addiction vulnerability and disordered eating. A subset of 101 students (50 binge-eaters and 51 non-binge eaters) also completed behavioral measures of the three posited mechanisms. The results of this study support the proposed model that weight and shape concerns moderate the relationship between addiction vulnerability and binge eating. Results also demonstrated on a behavioral task that individuals who endorsed binge eating were more likely to act impulsively and quit the PASAT-C task faster than control subjects. Furthermore, they demonstrated a greater increase in irritability while completing the task which may have resulted in their desire to quit the task earlier. No differences were found on behavioral measures of reward sensitivity (delay discount task) or cognitive control (stop signal task). Future studies should continue to examine the construct of addiction vulnerability to provide additional validity for the construct as well as examine it in the context of all forms of disordered eating.