Obsessive compulsive disorder and response inhibition: Meta-analysis of the stop-signal task.

Abstract

This systematic review and meta-analysis updates evidence pertaining to response inhibition in obsessive-compulsive disorder (OCD) as measured by the stop-signal task (SST). We conducted a meta-analysis of the literature to compare response inhibition in patients with OCD and healthy controls, metaregressions to determine relative influences of age and sex on response inhibition performance, and a risk of bias assessment for included studies using the Newcastle-Ottawa Scale (NOS). Stop-signal reaction time (SSRT), which estimates the latency of the stopping process deficit, was significantly longer in OCD samples than in controls, reflecting inferior inhibitory control (Raw mean difference = 23.43 ms; p = <.001; 95% CI [17.42, 29.45]). We did not observe differences in mean reaction time (MRT) in OCD compared with controls (Raw mean difference = 2.51 ms; p = .755; 95% CI [-13.27, 18.30]). Reaction time variability (RTSD) was reported in one study only. Age impacted effect size of SSRT, indicating inferior performance in older OCD patients than younger ones. We did not observe a significant effect of sex on SSRT or MRT scores. General Scientific Summary Difficulty inhibiting responses is an hypothesized deficit in obsessive-compulsive disorder (OCD). The results of this systematic review and meta-analysis of studies using the Stop Signal task support the notion of impaired response inhibition in OCD and indicate that older individuals with OCD show greater impairment than younger ones.