Twenty-one-year-old University of Pennsylvania lineman Owen Thomas, who had no previous history of depression, hanged himself in his apartment in April. But why? An autopsy report revealed that Thomas' brain tissue showed signs of early development of chronic traumatic encephalopathy (C.T.E.), a disease marked by depression and poor impulse control that has been primarily seen in NFL players (two of whom also committed suicide). So could Thomas' C.T.E. have contributed to his suicide? Researchers at Boston University's Center for the Study of Traumatic Encephalopathy are studying the disease in professional athletes, and until this point, have only seen one other clear case of C.T.E. in a non-NFL athlete. C.T.E. is linked to repetitive brain trauma, but its exact causes are unknown - Thomas' case could create more attention. So how does it all work and could other players be at risk? Head trauma in basketball players is also more prevalent; could C.T.E. become an issue there as well? Patt talks to the experts.