Football players may risk more than bruises and broken bones. Evidence is mounting that repeated concussions many pro athletes suffer can cause chronic traumatic encephalopathy (CTE), a degenerative brain disease marked by depression, dementia, and other Alzheimer's-like symptoms. But to find out the exact cause of CTE, researchers need to be able to study athletes' brains.
That's where NFL players come in. Keep clicking to meet players - some living and some deceased - who are in the vanguard of pro athletes to have donated or announced their intention to donate their brains to science.