American Board of Psychiatry and Neurology (ABPN) Practice Exam 2026 - Free ABPN Practice Questions and Study Guide

The caudate nucleus is a critical part of the basal ganglia and plays a significant role in various cognitive and motor functions, including the regulation of goal-directed behavior and the processing of feedback. In individuals with obsessive-compulsive disorder (OCD), structural and functional anomalies in the caudate nucleus have been consistently observed. These abnormalities are thought to contribute to the pathophysiology of OCD by affecting the pathways involved in habit formation and the filtering of intrusive thoughts, which are prominent features of the disorder. Neuroimaging studies have shown increased activity in the caudate nucleus during tasks involving compulsive behaviors, indicating its influential role in the manifestation of OCD symptoms.

The other brain regions listed, while essential for various cognitive processes and implicated in other psychiatric conditions, do not show the same level of consistent association with OCD. For instance, the hippocampus is primarily involved in memory formation, the corpus callosum facilitates communication between the two brain hemispheres, and the cerebellum primarily contributes to coordination and motor control. While structural differences or dysfunction can be present in these areas in some psychiatric conditions, they do not have the specific correlation with OCD symptoms that the caudate nucleus does.