The neurocircuitry of obsessive-compulsive disorder and disgust

Recent evidence from human research has indicated that discrete regions of the brain control different basic emotions. Whether the recognition and formulation of emotions truly stem from compartmentalized systems or arise from a multidimensional framework has yet to be elucidated, however. Disgust is a basic emotion that has been hypothesized to constitute an evolutionary function of contamination and disease avoidance. Disgust involves the appraisal of objects and events for their potential role in contamination, and OCD conceivably involves a dysfunction of this appraisal process. Disgust sensitivity has been shown to be positively correlated with OCD and to significantly predict contamination fear. Likewise, functional imaging studies of OCD patients with contamination concerns demonstrate activation of the same neural regions with disgust-inducing pictures as symptom relevant stimuli. Therefore, the neurocircuits involved in disgust processing may be relevant to OCD and, in particular, the contamination subtype. This review focuses on describing what is known to date concerning the neurocircuitry of disgust, and its relevance to the apparent neurocircuitry of OCD.