Participants will include 102 individuals (half female) between the ages of 18 and 55 with a current diagnosis of PTSD as measured by the Clinician Administered PTSD Scale for DSM-5 (CAPS-5). Participants must have a history of chronic childhood trauma due to relational abuse. All participants will be recruited from the McLean Hospital outpatient trauma track Cognitive Processing Therapy (CPT) treatment program.