Action inhibition in individuals with high obsessive-compulsive trait of incompleteness: An ERP study

Missing action completion signals are assumed to trigger repetitive behavior and feelings of the action "not being right". This proposal is based mostly on individual's self-reports. Here, we investigated the influence of experimentally manipulated action completion experience and the obsessive-compulsive (OC) trait of incompleteness on behavioral and neurophysiological measures of action inhibition.

Action completion was manipulated in an adapted Go/NoGo task, and OC trait incompleteness was assessed in healthy participants. More commission errors and faster responses were expected after missing action completion, especially for individuals with high OC trait incompleteness. The inhibition-related event-related potentials (ERPs) N200 and P300 were also measured.

High OC trait incompleteness led to more errors following omitted- and faster responses during commission errors following incongruent outcomes. Furthermore, lower N200 was associated with worse response inhibition, and high OC trait incompleteness was associated with reduced N200, but not reduced P300 amplitude. These findings provide evidence that trait-like feelings of incompleteness may underlie maladaptive action repetition and impaired inhibitory control as observed in OCD.