Agreed, xzins.
This is an interesting piece from Frontline about TBI's (Traumatic Brain Injury) and the impact it is having on our troops mental health.
Three stories from FRONTLINEs The Wounded Platoon
I believe SSGt Bales suffered a concussion in a prior deployment. I also believe the military said they do not have an official record of that injury, (after reading a bit from the Frontline piece, I guess that's not surprising.)