what is cte brain

Chronic traumatic encephalopathy (CTE) is a brain disorder that is likely caused by repeated head injuries. It is characterized by the death of nerve cells in the brain, known as degeneration, which gets worse over time. CTE is not related to a single head injury, but rather to repeated head injuries, often occurring in contact sports or military combat. The development of CTE has been associated with second impact syndrome, in which a second head injury happens before previous head injury symptoms have fully resolved. CTE is caused in part by repeated traumatic brain injuries, which include concussions and nonconcussive impacts. Experts believe that a structural protein in neurons called tau misfolds and malfunctions, causing adjacent proteins to misfold, and setting off a chain reaction where this malfunctioning tau slowly spreads throughout the brain, killing brain cells. CTE can only be definitively diagnosed by autopsy after death. Symptoms of CTE include mood changes, personality changes, behavior changes, short-term memory loss, confusion, impaired judgment, impulse control problems, aggression, depression, suicidality, parkinsonism, and eventually progressive dementia. It is thought that the only way to lower the risk of getting CTE is to avoid repeated head injuries.