Disease models of obsessive-compulsive disorder (OCD) propose that abnormalities in the cortico-striato-thalamo-cortical (CSTC) circuits are key to the pathophysiology of OCD. More recent findings also implicate the involvement of fronto-limbic and fronto-parietal regions in pediatric and adult OCD (1–3). An important limitation of brain imaging research is the typically small samples that limit sensitivity and presumably contributing to the lack of reproducibility and reliability (4). This issue may be partially addressed by the use of meta- and mega-analysis of multiple study samples. We therefore initiated the OCD working group within the Enhancing Neuro-Imaging Genetics through Meta-Analysis (ENIGMA) consortium (5) in which researchers around the world collaborate to boost statistical power, with the aim of elucidating brain abnormalities in OCD.
