Neural correlates of imbalanced habitual and goal-directed behaviors in obsessive-compulsive disorder

BACKGROUND: Compulsion is a core symptom of obsessive-compulsive disorder (OCD) and has been linked to an imbalance between habitual and goal-directed behaviors. However, the neural mechanisms underlying this imbalance, particularly the role of arbitration between habitual and goal-directed systems, remain unclear. METHODS: 31 patients with OCD and 39 healthy controls (HCs) underwent structural and functional MRI while performing the slips-of-action test (SOAT). Behavioral performance, task-related brain activation, and functional connectivity were compared between groups across habitual, goal-directed, and goal-habit competition conditions. RESULTS: During the slips-of-action test phase, OCD patients showed higher response rates to devalued stimuli and longer reaction times than HCs. Neuroimaging results revealed increased activation in the bilateral putamen and left insula during the habitual condition and reduced activation in the left caudate during the goal-directed condition. During the goal-habit competition condition, widespread hyperactivation was observed in cortical and subcortical regions in the OCD group. Psychophysiological interaction analyses revealed reduced functional connectivity between the right inferior frontal gyrus (IFG) and the left putamen, anterior cingulate cortex, orbitofrontal cortex, and lateral occipital cortex during the goal-directed condition. Compulsion severity was associated with greater right putamen activation and reduced connectivity between the IFG and left anterior cingulate cortex. CONCLUSIONS: These findings suggest that compulsive behavior in OCD is associated with impaired goal-directed behavior and excessive habitual responding, accompanied by alterations in IFG-centered regulatory networks that may contribute to impaired arbitration between habitual and goal-directed systems.