A researcher reports the brain of former NFL player and convicted murderer, Aaron Hernandez, shows severe damage in the area that controls behavior. The 27-year-old killed himself in April, while serving a prison sentence for murder.
Doctor Ann Mckee studies damage at the CTE Center at Boston University.
The disease shows up in people with multiple head injuries and Mckee said Hernandez's case was one of the most severe she had ever seen. Attorneys for the family have sued the NFL and helmet manufacturers, for failing to warn players about the dangers of football.