first started ct wasn't something people really knew much about. we've learned a lot since then. it stands for chronic traumatic encephalopathy, and it's kind of an alzheimer's like syndrome that has caused by repeated blows to the head concussions that people talk about when you get a concussion. it's the whole brain that is sort of affected by that, as opposed to a focal area of the brain, and it's that those repeated blows that have really been associated with concussions. we have a better idea of how this disease progresses over time. there are different stages. and the progression can happen over years, so stage one could be hardly any symptoms at all. stage two is when people start to possibly have behavioral outburst. severe depression stage three. you get even more symptoms layered on this, including memory loss. stage four is obviously the most advanced when you might even have psychotic symptoms. um again, drawing cause and effect here is a very challenging thing