reports on post-traumatic stress disorder and traumatic brain injury in troops returning from the wars in Iraq and Afghanistan. "Though thousands of soldiers are diagnosed with PTSD, many more suffer without treatment. Among those who do seek treatment, doctors are finding another, distinctly different problem called traumatic brain injury, or TBI. The two conditions have similar symptoms, but the causes are quite different. While PTSD is a psychological disorder that can be treated with medication and therapy, TBI is physical injury to the brain that requires cognitive treatment to help rebuild function. 'Fundamentally, PTSD is a disorder where you remember too much, whereas TBI is a disorder where you don’t remember enough,' says Dr. Gregory O’Shanick, National Medical Director for the Brain Injury Association of America (9/4).