Treatment outcome of posttraumatic stress disorder: A white matter tract analysis

Despite the development of empirically supported treatments for posttraumatic stress disorder (PTSD), many individuals remain symptomatic following therapy or dropout prematurely. Neuroimaging studies examining PTSD treatment outcome may offer valuable insights into possible mechanisms that may impact treatment efficacy. To date, few studies of PTSD have used neuroimaging to examine symptom change following completed treatment, and most have focused on gray matter. Studies of white matter are equally important, as changes in white matter integrity (WMI) are connected to a host of detrimental outcomes. The current study examined symptom change of 21 women with PTSD as a result of interpersonal violence who received baseline diffusion tensor imaging (DTI) scans and completed 12 weeks of Cognitive Processing Therapy (CPT). After controlling for baseline PTSD severity, fractional anisotropy (FA) in the left internal capsule, posterior limb of the internal capsule, left cingulate gyrus, superior longitudinal fasciculus, and splenium of the corpus callosum was predicted by PTSD symptom change. Results contribute to understanding neural changes within therapy and may assist in predicting individual treatment response. Namely, by identifying areas potentially impacted by PTSD treatment, future studies may be able to connect the function of these white matter areas to better predict patient PTSD treatment outcome.