Chronic traumatic encephalopathy (CTE), a form of tauopathy, is a progressive degenerative disease found in people who have had a severe blow to the head.

CTE has been most commonly found in professional athletes participating in American football, association football, ice hockey, professional wrestling, stunt performing, bull riding, bicycle motocross, rodeo, and other contact sports who have experienced repeated concussions or other brain trauma. Its presence in domestic violence is also being investigated. It can affect high school players who have played for just a few years.

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