Developed with Department of Defense funding by Albert “Skip” Rizzo and Arno Hartholt, both at the University of Southern California, Bravemind is used to treat PTSD at about 100 U.S. sites. ... Until recently, large-scale studies of VR have been missing in action. This is changing fast with the advent of cheaper, portable systems. Difede, Rizzo and three others just completed a randomized controlled trial with nearly 200 PTSD patients. ...