McHale, who played for the Tampa Bay Buccaneers, was a Cornell graduate, a former restaurateur, husband and the father of three boys. His widow Lisa said at the news conference that he began using powerful drugs, such as OxyContin, to control chronic pain in his shoulders and other joints.
She said the medication exacerbated his lethargy and depression, so he occasionally took cocaine to offset the effects. He went through drug rehab three times, but died of an accidental overdose of the two drugs last year.
McKee said independent experts agreed the drugs could not have caused the brain damage she observed. That damage, and the injuries to the 18-year-old, were confirmed in an independent autopsy by Dr. E. Tessa Hedley-White of Massachusetts General Hospital.
Other NFL players who exhibited similar brain injuries after their premature deaths included Pittsburgh Steelers Mike Webster, Terry Long and Justin Strzelczyk; 12-year NFL veteran Andre Waters, known as one of the game's hardest hitters; and John Grimsley, an eight-year veteran and Pro Bowl player.
The Tampa news conference was co-sponsored by the Sports Legacy Institute, founded by former Harvard football player and World Wrestling Entertainment wrestler Chris Nowinski, which is also a sponsor of the Boston University traumatic encephalopathy center.
Nowinski said Tuesday that several former NFL players have recently agreed to donate their brains to the center upon their deaths for further study. Most are members of the NFL's 88 Plan, named after the jersey number of former Baltimore Colts tight end John Mackey, who suffers from severe dementia. The 88 Plan is designed to provide financial assistance to families of former players who are suffering from dementia.
Dr. John P. DiFiori, who is chief of the division of sports medicine at UCLA's David Geffen School of Medicine and a physician for Bruins teams, said he hoped the reports would increase "recognition that concussions are a serious injury and that symptoms should not be ignored."
Young athletes often do not recognize the symptoms -- which include headache, dizziness, nausea and changes in emotional status -- or ignore them "because they want to stay in the game," he said. The studies show the importance of getting treatment to prevent further damage, he concluded.