the cortical abnormalities in currently medicated OCD patients could reflect persistent abnormalities related to increased OCD severity before treatment. In addition, medication effects persisted after adding a covariate correcting for illness severity (data not shown). The lack of association between severity according to the (C)Y-BOCS and cortical measures could be due to medication reducing the symptom severity. Additionally, current symptom severity might not be optimal to capture the long-term disease severity.
