Fear extinction learning as a predictor of response to cognitive behavioral therapy for pediatric obsessive compulsive disorder

Background: While cognitive behavior therapy (CBT) is an effective treatment for many children and adolescents with Obsessive Compulsive Disorder (OCD), therapeutic response is variable. Fear conditioning and extinction are central constructs underlying exposure-based CBT. Fear extinction learning assessed prior to CBT may be a useful predictor of CBT response for guiding treatment decisions. Methods: Sixty-four youth who participated in a randomized placebo-controlled trial of CBT with and without d-cycloserine (DCS) completed a fear conditioning task. Skin conductance response (SCR) scores were used to measure fear acquisition and extinction to determine whether extinction learning could predict CBT response. Results: CBT responders and non-responders appeared to acquire conditioned fear SCRs in a similar manner. However, differences between treatment responders and non-responders emerged during the extinction phase. A responder (responder, non-responder) by conditioned stimulus type (CS+, CS−) interaction showed that CBT responders differentiated the stimulus paired with (CS+) and without (CS−) the unconditioned stimulus correctly during early and late extinction, whereas the CBT non-responders did not (p =.004). Conclusions: While the small sample size makes conclusions tentative, this study supports an emerging literature that differential fear extinction may be an important factor underlying clinical correlates of pediatric OCD, including CBT response.