OCD as a Failure to Integrate Goal-Directed and Habitual Action Control
This chapter discusses the considerable research that has identified distinct functional circuits linking frontal cortex with the basal ganglia in the control of goal-directed and habitual actions. OCD is characterized by hyperactivity in a circuit involving some of these regions. Recent accounts of the interaction of goal-directed actions and habits suggest that these control processes interact hierarchically, so one alternative to current theories is that OCD reflects a dysfunction in this interactive process resulting in dysregulated action selection, whether that selection is driven by the outcome itself or by cues predicting the outcome. Importantly, it appears that both sources of action selection depend on the OFC—outcome based retrieval on the medial OFC and cue-related retrieval on the lateral OFC. From this perspective, therefore, hyperactivity of the OFC could produce both elevated outcome retrieval and increased responsiveness to outcomes-related cues, resulting in dysregulated action selection and compulsive action initiation as a consequence.