Differential neural predictors of treatment response for fear and dysphoric features of posttraumatic stress disorder

Background Although trauma-focused cognitive behavioral therapy (TF-CBT) is the frontline treatment for posttraumatic stress disorder (PTSD), at least one-third of patients are treatment nonresponders. This study aimed to identify neural markers of treatment response, specifically the prediction of remission of specific PTSD symptoms. Methods This study assessed PTSD treatment-seeking patients (n = 40) before TF-CBT during functional magnetic brain resonance imaging (fMRI) when they processed fearful, sad, happy, and neutral faces. Patients underwent nine sessions of TF-CBT and were independently assessed on the Clinician-Administered PTSD Scale (CAPS) following treatment. Treatment responders and nonresponders were compared with healthy controls (n = 40). The severity of PTSD was assessed with the CAPS. fMRI responses were calculated for each emotion face compared to neutral contrast, which were correlated with reduction in PTSD severity from pretreatment to posttreatment. Treatment response was categorized by at least 50% reduction in the severity of PTSD. Results The activation of left insula during the processing of both sad and fearful faces was associated with a greater reduction of fear but not with dysphoric symptoms after treatment. Connectivity of the left insula to the pregenual anterior cingulate cortex was associated with poorer response to treatment. Responders and controllers had similar levels of activation and connectivity and were different from nonresponders. Conclusions Positive response to TF-CBT is predicted during emotion processing by normal levels of recruitment of neural networks implicated in emotional information. These findings suggest that distinct neural networks are predictive of PTSD fear and dysphoric symptom reduction following TF-CBT.