Anybody watching League of Denial on PBS?
… One of the more startling revelations from the film is that football players don’t need to sustain any kind of freak, horrific blows to the head to become afflicted with CTE, or chronic traumatic encephalopathy, which causes depression, mood swings, and memory loss, and has been blamed in the suicides of a number of former players. You don’t even need to have ever suffered a concussion. The sport itself — the repeated trauma to the head that is an inevitable part of the gameplay — is the culprit. And you don’t even need to play for very long…
Much more, including a rather gruesome clip, at the link.