Virtual Reality Therapy and Imaging in Combat Veterans With Blast Injury and Posttraumatic Stress Disorder

The investigators have previously demonstrated that military service members (SMs) with PTSD related to deployment to Iraq or Afghanistan have fMRI brain activation patterns similar to those reported in other populations with PTSD. The investigators have also demonstrated significant improvements, or normalization, in the activation of each of these brain areas following exposure therapy. In this study the investigators will assess recovery in SMs receiving virtual reality exposure therapy, comparing them to healthy veterans, those with history of blast exposure and those with PTSD receiving usual care. The investigators hope to (1) demonstrate that fMRI can distinguish between military service members with PTSD, with mild TBI, and those who have neither; (2) demonstrate that significant differences are not seen in brain activation patterns merely by repeating fMRI scans at 3 month intervals but when significant changes are present they in fact represent the effect of the exposure therapy intervention; (3) discern whether those with PTSD after TBI have different activation patterns than those with PTSD in the absence of TBI; and (4) identify fMRI characteristics of resilience in service members who have been deployed but did not develop PTSD.