(PS7-19) OC Severity, Symptom Accommodation and Repeated Decision Making

Obsessive-compulsive disorder (OCD) is a debilitating psychiatric condition that affects approximately 1-3% of the global population. A significant feature of OCD is the compulsion to perform checking behaviors. Despite its prevalence and impact, the cognitive mechanisms underlying excessive checking are not fully understood, though the compulsive need to check and recheck indicates a possible impairment in repeated decision making.

Using a translational approach, we collected data from college students (n=100, 65% BIPOC, 69% female) with various levels of obsessive-compulsive (OC) symptoms using an online repeated decision-making task adapted from Solway et al., 2021. The goal of this study is to dissect altered decision-making processes affected by OC symptoms, as well as by OC symptom accommodation (SA) made by others. We hypothesized that specific decision mechanisms under differing decision contexts would correlate with OC severity and levels of SA. 

Participants completed an online perceptual decision-making task (i.e. the adapted Repeated Dot Motion Task). In the first phase of the task, participants made an initial dot motion decision for each trial, which was tagged with a unique word as a memory cue. In the second phase, participants engaged in two counterbalanced types of trials: revisit trials and memory trials, cued by the associated word, where participants were either asked if they wanted to revisit their decision, or to indicate the decision they made in the first phase. After the task, participants were asked to complete additional measures assessing aspects of OC symptoms and other mental health information, including a symptom accommodation scale adapted from the Family Accommodation Scale for OCD.

Trial-by-trial reaction times and decisions were fitted via STAN under a hierarchical Bayesian diffusion-drift model, using trial difficulty, OC severity, and SA as regressors. Preliminary analysis on first-phase decisions showed that OC symptom severity was not associated with changes in decision parameters during initial decision-making, while higher SA was associated with significantly lower rate of evidence accumulation for decisions, as represented by a lower drift rate (95% CI = [-0.110, -0.008]). All model parameters converged well (Gelman–Rubin R_hat < 1.1). These initial findings suggest that SA may play a more direct role than OC symptoms in disrupting decision-making, potentially reinforcing maladaptive checking behaviors especially in non-clinical high OC individuals. The association between SA and suboptimal decision-making highlights the need to address accommodation as a distinct therapeutic target. Our sample reflects a range of racial, ethnic and gender experiences, strengthening the generalizability of our SA finding to heterogeneous lived experiences. Further research should investigate how cultural, familial, or socioeconomic factors influence patterns of accommodation and their effect on decision-making in individuals with OC symptoms.