It is the fact that boxers handle to many hits in the head. This amount of hits can provide real brain damage. It’s well known that Muhammad Ali is suffering from Parkinson disease, but it’s not well known that Mike Tyson has some issues too. I’m not sure was he like this before he start boxing, but now he talks like a real retard. When I heard that he wrote a book I was really surprised. How someone who talks like this can write a book? If you ask me, this is a case for the X Files