Dr. Bennett Omalu has identified signs of CTE for the first time in someone while they're still alive.

Fred McNeill had CTE and signs of the disease were identified while he was still alive.

McNeill is the first ex-NFL player in the study to have died.

Tony Dorsett and Joe DeLamielleure are also in the study.

Many scientists attribute CTE to repetitive brain injuries and consider it a cause of memory loss, dementia and depression. 

The New York Times also reported on Thursday that Hall of Fame safety Willie Wood, who is 79, has no memory of playing Super Bowl I and is suffering from dementia.