Advances in the neurobiology of obsessive-compulsive disorder: Implications for conceptualizing putative obsessive-compulsive and spectrum disorders

Several approaches to the spectrum of obsessive-compulsive spectrum disorders have been put forward, each based on a rather different framework. To some extent, overlaps exist among these approaches, indicating that the neurobiology of OCD and related disorders is increasingly consolidated; however, important differences exist between these approaches, and many questions are unanswered, demonstrating that more work is necessary to fully delineate OCD and its subtypes and their relationships to other putative obsessive compulsive spectrum disorders. Despite the need for substantial additional research on the neurobiology of the obsessive-compulsive spectrum, this construct already has heuristic value in the clinical and research setting. It reminds clinicians to ask OCD patients about comorbid spectrum disorders, and it suggests the possible value of anti-OCD agents and behavioral techniques in patients for whom treatments were previously unavailable. It reminds investigators to consider possibly overlapping and differentiating mechanisms in several disorders. Ultimately, the delineation of such mechanisms will allow for a more rigorous approach to the putative obsessive-compulsive spectrum disorders.