Category: Obsessive Compulsive and Related Disorders
Response inhibition (RI) is a core cognitive capability involved in stopping responses and behaviors that are inappropriate or no longer necessary (Verbruggen & Logan, 2009). RI is measured through the stop-signal task (SST), which produces one core variable of RI (stop-signal reaction time (SSRT) (Logan et al., 1994)). Recently, multiple sub-processes of SST performance have recently emerged to complement SSRT; most notably, researchers have begun to examine the phenomenon of error-monitoring, or, an adjustment of performance dependent of detection of errors (Schachar et al., 2004). Error-monitoring is typically understood as a global slowing of responses following failed inhibition trials compared to successful ones (Li et al., 2008). Thus far, the error-monitoring phenomenon is understudied in the context of individuals with obsessive-compulsive disorder (OCD), which is characterized by noted deficits in inhibition on SSRT (Chamberlain et al., 2006). Here, we investigate the presence of error-monitoring in SST performance in the context of an OCD community sample. Thirty-three (n=33) individuals were recruited from the Milwaukee community as part of a clinical trial for OCD, assessed for diagnostic status and administered the SST. Consistent with Li et al. (2008), we extracted three relevant variables from the SST to characterize error-monitoring: average reaction time on ‘go’ trials following other go trials (pG), average reaction time on go trials following successful stop trials (pSS), and average reaction time on trials following unsuccessful inhibition (pSE). These variables were entered into a repeated measures ANOVA to detect significant differences between them; theoretically, greater slowing on pSE vs. pSS and pG trials would indicate the presence of post-error slowing (Bissett & Logan, 2011). Indeed, we observed that the mean reaction time on pSE trials (mean=736.2ms, SD=30.4) was significantly greater than the reaction time on both pSS trials (mean=690.6ms, SD=27.5) and pG trials (mean=680.6, SD=27.96) (F(1, 31) = 626.94, p < .001). Findings indicate that in the context of OCD, individuals are more likely to slow their responses on go trials following failed inhibition trials than on both successful inhibition and simple go trials, thus demonstrating the presence of error monitoring in this condition.
Gregory Berlin– Graduate Student, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin
Taylor Davine– Graduate student, University of Wisconsin-Milwaukee
Abel Matthew– Graduate Student, University of Wisconsin-Milwaukee
Jamie Garrow– Research Assistant, University of Wisconsin-Milwaukee
Colleen Stock– Research Assistant, University of Wisconsin-Milwaukee
Hanjoo Lee– University of Wisconsin-Milwaukee