Something strange and deadly is happening inside the brains of top athletes -- a degenerative condition, possibly linked to concussions, that causes dementia, psychosis and far-too-early death. It's called chronic traumatic encephalopathy, or CTE, and it's the medical mystery that Chris Nowinski wants to solve by analyzing brains after death. It's also why, when Nowinski meets a pro athlete, his first question is: "Can I have your brain?" Hear more from this ground-breaking effort to protect athletes' brains -- and yours, too.