Inhibitory control and decision making under risk in bulimia nervosa and binge-eating disorder

Abstract

Objective: To investigate neuropsychological mechanisms of impulsivity in patients with bulimia nervosa (BN) and binge-eating disorder (BED).

Method: Nineteen BN patients and 31 age- and body-mass-index (BMI)-matched healthy controls (c-BN) as well as 54 overweight and obese BED patients and 43 age- and BMI-matched healthy controls (c-BED) were investigated using an inhibitory control task (stop signal task, SST) and a decision-making under risk task (game of dice task, GDT).

Results: Compared to c-BN, BN patients demonstrated significant greater stop signal reaction times in the SST, but no differences for the frequency of risky decisions in the GDT. BED patients did not differ from c-BED in the SST or the GDT.

Discussion: BN but not BED patients differed from their respective control groups concerning the "stopping" component of impulsivity. These differences in motor inhibition may contribute to the behavioral distinctions in binge-eating behavior between BN and BED.

Keywords: binge-eating disorder; bulimia nervosa; decision making; impulsivity; inhibitory control; neuropsychology.