Serious brain trauma often leads to chronic traumatic encephalopathy, CTE, in otherwise healthy individuals. CTE is at the center of the debate concerning concussions and brain injuries in professional athletes, as several were diagnosed with this condition posthumously. CTE is a neurodegenerative disease linked to dementia, memory loss and depression. Until now, it could only be diagnosed once the victim had died. New technology at UCLA, however, allows brain scans of living persons to reveal images of the protein in the brain that indicates development of CTE. That protein, tau, builds up and strangles brain cells after repeated head injuries. The protein was found in five former professional football players in this recent study at UCLA, and is concentrated on the areas of the brain controlling emotion and memory. This new find will likely prompt urges for mandatory testing of athletes to determine if they are at risk for serious conditions in the future, and will also allow further research to create treatments to prevent further development of CTE when present in an athlete.
The CDC provides more information through its "Heads Up: Concussion in Youth Sports" initiative.