Aggression, explosivity linked to multiple concussions in new study

A new study of brains donated after death details the degenerative brain disease that afflicted 68 of 85 subjects who suffered multiple concussions during stints in the military or in organized sports. Among the deceased athletes whose brains were examined for the study were NFL Hall of Famers John Mackey, a tight end, and running back Ollie Matson, both of whom died in 2011 of dementia complications.

By Melissa Healy

December 4, 2012