Emotional Interference of Response Inhibition in Obsessive-Compulsive Disorder

Researchers have hypothesized that failures of inhibition are partially responsible for habitual and perseverative symptoms that are unique to Obsessive-Compulsive Disorder (OCD). It is also well known that sequelae of emotional processes are also implicated in the etiology and maintenance of obsessions and compulsions. However, little research has tested how emotional processes moderate inhibitory functions in OCD. In the present study, high contamination phobic (HCP, n = 17) and low contamination phobic (LCP, n = 30) participants completed an emotional go/no-go task, which measured the interfering effects contamination-threat processing on action restraint. The present study had a two level between-subjects-quasi-independent factor (Group: LCP vs. HCP), and a two level within-subjects-experimental-factor (Threat: Contamination vs. Neutral). The proportion of errors of commission (failures of action restraint) was the primary dependent variable. There were three predictions: 1) for the main effect of Threat, it was predicted that the visual processing of contamination images would significantly interfere with action restraint (Contamination errors of commission \u3e Neutral errors of commission); 2) for the main effect of Group, it was predicted that HCP participants would show poorer action restraint when compared to LCP participants (HCP errors of commission \u3e LCP errors of commission); 3) for the Group x Threat interaction, it was predicted that the visual processing of contamination images would interfere more with action restraint among HCP than LCP participants (Contamination errors of commission among HCP participants \u3e Neutral errors of commission among HCP participants, Neutral errors of commission among LCP participants, and Contamination errors of commission among LCP participants). Predictions 1 and 3 were supported by results while results failed to support the second prediction. These data suggest that the processing of emotionally arousing imagery interferes with action restraint and the magnitude of this effect is greater among an analogue OCD sample reporting contamination symptoms. These findings are clinically relevant and significantly extend etiological models of OCD by integrating basic neurocognitive and affective mechanisms. The unique and complimentary roles of emotional, attentional, and inhibitory processes in the etiology and maintenance of obsessions and compulsions are explored and updates to models of OCD are discussed