Amygdala Volumetric Change Following Psychotherapy for Posttraumatic Stress Disorder

The authors investigated the impact of eye movement desensitization and reprocessing (EMDR) and prolonged exposure (PE) on the volumes of the amygdala and hippocampus, structures known to be important in fear conditioning, in 20 patients with posttraumatic stress disorder (PTSD). Patients were randomly allocated to either EMDR or PE. Volumes were assessed before and after treatment via magnetic resonance imaging (MRI). Both groups showed significant improvements in PTSD symptoms. Left amygdala mean volume increased significantly following EMDR treatment only. No significant volumetric changes were found for the hippocampus.