Fast psychomotor functioning in underweight anorexia nervosa patients

Abstract

To explore whether underweight anorexia nervosa patients show psychomotor differences relative to normal controls, 32 female hospitalised patients, aged between 14 and 25 years, were compared with 32 healthy, normal weight controls, matched for sex, age and educational level. Using computerised analysis of writing and drawing behaviour, reaction times and movement times and their different components were analysed, while cognitive and motor demands were manipulated in five drawing and copying tasks. Anorexia nervosa patients were, compared to normal weight controls, significantly faster in a drawing task and showed shorter reaction times in copying tasks. Movement times did not differ significantly between the two groups. In the most complex copying task, a significant group x complexity interaction for reaction time (patients shorter) and reinspection time (patients longer) was found. Patients also made more errors than controls. The finding of a consistent pattern of shorter reaction times in underweight anorexia nervosa patients seems to run contrary to previous findings of disturbed cognitive functioning (i.e. impaired attention) in these patients. The differences seem to be related to cognitive factors more than to motor (executive) components.