When I heard that Chris Benoit murdered his family and then killed himself, my first thought was to wonder if he had dementia associated with repeated blows to the head. There have been a number of professional athletes (mostly football players) that have suffered from this due to repeated blows to the head and undiagnosed concussions, whose cumulative effects destroyed the athletes' brain.
Today, an ABC News story today states that was, in fact, a condition from which Benoit suffered.
According to Michael Benoit, Chris' father, tests conducted by Julian Bailes of the Sports Legacy Institute show that Benoit's brain was so severely damaged it resembled that of an 85-year-old Alzheimer's patient. Bailes and his research team say that this damage was the result of a lifetime of chronic concussions and head trauma suffered while Benoit was in the wrestling ring.
Benoit was famous for his flying headbutt, which put stress on his brain every time he did it. It's now entirely possible that we know why he committed the acts.