In what The Boston Globe is calling the most extensive study of its kind to date, researchers at Boston University have found that the brains of deceased athletes and military veterans had signs of brain damage after repeated head injuries.
The results are from the autopsies of 85 brain donors, including two high school football players who died in their teens. The study comes amid increasing concerns about the dangers of head injuries in contact sports.
Boston University neurosurgeon Robert Cantu, who co-authored the paper, said the sheer size of the study should put to rest any doubt that chronic traumatic encephalopathy - a progressive and degenerative disease of the brain - is real, and is caused by repeated head injuries.
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This segment aired on December 3, 2012.