Scientists hope a high-tech virtual experience that mimics the battlegrounds of Iraq can be used to help veterans recover from the trauma of war. The Emory University study is designed to help find a new way to reduce or eliminate symptoms of post-traumatic stress disorder, a condition that affects up to one-third of Iraq War veterans. Virtual reality "exposure" therapy has been used to fight post-traumatic stress for a decade. The Emory study of 150 soldiers with PTSD is trying to prove that virtual reality can work better and faster when subjects take a drug once widely used to treat tuberculosis. The drug, d-Cycloserine or DCS, affects a region of the brain called the amygdala that processes memories and emotional reactions such as fear. Research shows the drug can decrease fear. Aaron Beach, a 23-year-old Army veteran, is enrolled in the study. He smells burning rubber, diesel fuel, even body odor as he sits behind the steering wheel of his Humvee in the virtual experience. Suddenly, gunfire crackles and Beach feels a jolt as a rocket-propelled grenade blasts his vehicle, shattering his hand and wounding a buddy. "It puts you back there, for sure," Beach said. "The stuff doesn't look totally real, but it all feels real. It's scary." The problem for Beach is the scene also plays out in his head when he is not wearing the virtual reality helmet. In everyday life, visions of Iraq come to Beach when he hears a loud noise, closes his eyes, rides his motorcycle, is in crowds or even when he spots garbage or parked cars on the roadside. Neither Beach nor the scientists yet know whether he is taking DCS, a tranquilizer or a placebo. But Beach says he is less jumpy and is feeling better after five sessions. During the sessions, the soldiers often get nervous. A few have had to take off helmets for a break. Others have cried. "I am deeply touched by the pain I witness," said Dr. Maryrose Gerardi, who runs the lab, "and it's always an honor for me to be allowed to share it."