From World War Two, to Iraq and Afghanistan when troops like Megan Krause come home, many of their minds are still at war.
"I ended up thinking somehow that there were terrorists chasing me," said Sgt. Megan Krause, veteran.
93-year-old John Cicha has vivid memories as a POW during World War Two.
"You never forget that stuff. Never. Never," said John Cicha, POW Survivor.
John still lives with post traumatic stress disorder. Psychologist Brian Engdahl says that reaction is a Hallmark of the condition. He's heading a two year study on magnetoencephalography, or MEG to see PTSD.
"That brain pattern is so different that it allows us to identify them from people who don't have PTSD," said Brian Engdahl, Ph.D., Psychologist Brain Sciences Center.
MEG measures magnetic fields in the brain. It shows patterns of miscommunication that identify PTSD. Another new study testing vets with the imaging system asks them to do different tasks while in an MEG.The brain activity of PTSD vets is then compared to the results of vets without it. The main goal is to define PTSD bio-markers to diagnose it, treat it quickly and track responses to treatment. While Engdahl isn't involved in this particular study, he's excited about MEG's possibilities.
"This would be, we believe, one of the first biological markers of a mental disorder."
As for John, he's still dealing with his demons. But with this technology, the next generation of heroes might not have to.