ENIGMA-OCD is a working group of the ENIGMA consortium aimed at bringing OCD research groups together to share neuroimaging and genetic databases. Prof. Odile van den Heuvel is chair of this working group.

    Currently the ENIGMA-OCD working group is an international collaboration including 32 research groups from 16 different countries worldwide. The ENIGMA-OCD Working-Group performed the largest study to date of brain structure in adult and paediatric OCD, employing both meta- and mega-analysis (Boedhoe et al. 2016, Am J Psychiatry). We analysed T1-weighted brain MRI scans from 1,830 OCD patients and 1,759 controls across 35 cohorts worldwide.

    OCD patients showed consistent abnormalities in the thalamus (in children) and the pallidum (in adults). Our findings demonstrate a key role for the thalamus (in children) and the pallidum (in adults) in the pathophysiology of OCD. These differential findings across the life-course in OCD further emphasize the neurodevelopmental aspect in the pathophysiology of the disorder and suggest that further research on neuroplasticity in OCD may be useful. Therefore, we are currently following up with a meta- and mega-analysis of cortical measures such as cortical thickness and surface area.