Approach and avoidance motivation in eating disorders.

It has been proposed that approach and avoidance processes may be critically involved in the development and maintenance of eating disorders (EDs), including anorexia nervosa (AN) and bulimia nervosa (BN). The Behavioural Inhibition System and Behavioural Activation System Scales (BIS/BAS) and Appetitive Motivation Scale (AMS) questionnaires were administered to 286 participants: 91 healthy controls (HCs), 121 participants with a current ED, either AN (restrictive and binge purge subtypes), or BN and 74 participants recovered from an ED. Individuals with EDs had higher levels of sensitivity to punishment and lower levels of reward reactivity than controls. Individuals in recovery from an ED scored the same as those in the acute group, with the exception of BAS fun seeking, for which they scored significantly higher than those with restricting AN. Discriminant analysis revealed that HCs were maximally separated from those in the acute and recovered ED groups along a dimension reflecting high punishment sensitivity and low reward sensitivity. Classification analysis demonstrated that ED and HC group membership was predicted from reward and punishment sensitivity measures; however recovered participants tended to be misclassified as ED. This study suggests high punishment sensitivity and low reward reactivity/sensitivity might form a personality cluster associated with the risk of developing an ED.