Memory for Actions in Obsessive-Compulsive Disorder

Abstract

Frequent checkers with obsessive-compulsive disorder (OCD; n=24), high checking controls (n=24) and low checking controls (n=48) were instructed to learn action phrases such as “to open the book” by performing the action themselves with imaginary objects (motor encoding), by imagining how one performs the action oneself (motor-imaginal encoding), by imagining seeing somebody else performing the action (visual-imaginal encoding) and by subvocal rehearsal. Compared to low checking controls, OCD checkers showed poorer free recall of motorically encoded actions and poorer reality monitoring, i.e. they confused motor and motor-imaginal encoding more frequently. The results are consistent with a specific motor memory deficit in OCD checkers. Moreover, memory performance of OCD checkers differed from that of high checking controls.