Hippocampal gray matter increases following multimodal psychological treatment for combat‐related post‐traumatic stress disorder

Smaller hippocampal volumes are one of the most consistent findings in neuroimaging studies of post‐traumatic stress disorder ( PTSD ). However, very few prospective studies have assessed changes in hippocampal gray matter prior to and following therapy for PTSD , and no neuroimaging studies to date have longitudinally assessed military populations. Methods A pilot study was conducted, assessing patients with combat‐related PTSD with structural MRI . Participants were then assigned either to a treatment group or waiting‐list control group. After the treatment group received multimodal psychological therapy for approximately 6 weeks, both groups completed a second neuroimaging assessment. Results Region‐of‐interest analysis was used to measure gray matter volume in the hippocampus and amygdala. There was a group by time interaction; the therapy group ( n  = 6) showed a significant increase in hippocampal volume and a nonsignificant trend toward an increase in amygdala volume following therapy, while no change was observed in the waiting‐list group ( n  = 9). Conclusions This study provides initial evidence for increases in gray matter volume in the hippocampus in response to therapy for combat‐related PTSD .