Dave Duerson

Safety Dave Duerson won a Super Bowl as a cog in the 1985 Bears defense. In February 2011, Duerson, 50, texted to his ex-wife Alicia an odd request: "Please, see that my brain is given to the N.F.L.'s brain bank." When Duerson's body was found, there was a handwritten suicide note repeating the request. "I think David knew that inside of him there was something wrong," Alicia told the New York Times.

Duerson's family complied with his last request, donating his brain to the Center for the Study of Traumatic Encephalopathy (CSTE). In May 2011, doctors at the CSTE confirmed Duerson had "indisputable evidence" of CTE.

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