Neurological Underpinnings of Psychological Factors Distinguishing Obsessive-Compulsive Disorder From Misophonia

Abstract

Several studies have suggested that misophonia should be categorized as an obsessive-compulsive disorder (OCD) due to similar neural manifestations, such as impairments in limbic structures, and psychological features, such as perfectionism and disgust sensitivity. However, the two disorders may differ in the domains of disgust sensitivity. In OCD, the domain of pathogen disgust has been studied extensively as per the contamination subtype. In misophonia, pathogen disgust has not been reported. We hypothesized that moral disgust may better characterize individuals with misophonia, as studies indicate that people with misophonia view their triggers as morally unacceptable. Furthermore, neuroimaging has shown anterior cingulate cortex (ACC) activation particularly during exposure to misophonic triggers, which is an area associated with moral assessment of stimuli. Another psychological factor that may point to the two disorders being discrete is intolerance of uncertainty (IU), an aversion to undetermined events. IU has been well documented in OCD: It has been found to be positively associated with striatal volume and dysfunction in the ACC—both of which are common findings in OCD. We expected people with misophonia not to exhibit IU since they experience distress in response to specific triggers and, unlike individuals with OCD, do not experience preemptive anxiety. Multivariate logistic regression analysis run on survey-gathered data revealed IU as a significant predictor of OCD symptoms and moral disgust as a significant predictor of misophonia. Consistent with our hypotheses, our findings suggest that IU and moral disgust and the associated neural underpinnings differentiate misophonia from OCD. [ Psychiatr Ann . 2023;53(12):570–580.]