Psychophysiology during exposure to trauma memories: Comparative effects of virtual reality and imaginal exposure for posttraumatic stress disorder.

BACKGROUND This investigation involved an in-depth examination of psychophysiological responses during exposure to the trauma memory across 10 sessions among active duty soldiers with combat-related posttraumatic stress disorder (PTSD) treated by Prolonged Exposure (PE) or Virtual Reality Exposure (VRE). We compared psychophysiological changes, session-by-session, between VRE and traditional imaginal exposure. METHODS Heart rate (HR), galvanic skin response (GSR), and peripheral skin temperature were collected every 5 min during exposure sessions with 61 combat veterans of Iraq/Afghanistan and compared to the PTSD Checklist (PCL-C) and Clinician-Administered PTSD Scale (CAPS) outcomes using multilevel modeling. RESULTS Over the course of treatment, participants in the PE group had higher HR arousal compared to participants in the VRE group. With reference to GSR, in earlier sessions, participants demonstrated a within-session increase, whereas, in later sessions, participants showed a within-session habituation response. A significant interaction was found for GSR and treatment assignment for within-session change, within-person effect, predicting CAPS (d = 0.70) and PCL-C (d = 0.66) outcomes. CONCLUSION Overall, these findings suggest that exposure to traumatic memories activates arousal across sessions, with GSR being most associated with reductions in PTSD symptoms for participants in the PE group.