Former Atlanta Falcons safety Ray Easterling, who suffered several concussions playing football during the 1970s, died on Thursday at the age of 62, his wife confirmed on Sunday.
Local media quoted police as saying that Easterling committed suicide by shooting himself in the head.
He was one of seven former NFL players who filed a lawsuit against the league last year, accusing it of concealing links between football and brain injuries.
"The goal is to see that the NFL takes responsibility for what they tried to bury for so many decades and establish a fund for players to access when they find that they're in (situations like Easterling's)," his wife, Mary Ann Easterling, said.
Easterling was a safety for the Atlanta Falcons from 1972 to 1979 and was part of the team's "Gritz Blitz" defense in 1977, setting a league record for fewest points allowed in a season.
Mary Ann Easterling said she began noticing changes in her husband's personality about 20 years ago, and the severity of the symptoms grew over the years.
"He had difficulty with insomnia ... began dealing with depression," she said, adding that she suspected dementia after reading about other former NFL players with similar problems.
Ray Easterling was diagnosed with dementia a year ago.
Former Chicago Bears Super Bowl-winning quarterback Jim McMahon is also among the seven who filed the high-profile lawsuit against the NFL.
He told Reuters early last year that while he could "kind of remember" winning a Super Bowl, he had difficulty remembering simple things, such as why he had walked into a room.
The NFL has dismissed allegations that it deliberately misled players.
The league has also created a concussion awareness website and has levied heavy fines on players for helmet-to-helmet hits during recent seasons.
Easterling's wife said he had relentlessly battled dementia and had continued to go jogging in his Richmond, Virginia neighborhood after the diagnosis.
"Neighbors would go out and encourage him. If he looked like he was going to stumble or not be able to get back, they would help him out," she said.
"I've just come off an evening of people sharing memories of him and how much he meant to them," she said, shortly after a house gathering. "It's made me love him that much more."
