CTE or Chronic Tramatic Encephalopathy is defined by the Boston University CTE Center as a degenerative brain disease found in athletes, military veterans, and others with a history of repetitive brain trauma. In CTE, a protein called Tau forms clumps that slowly spread throughout the brain, killing brain cells. CTE has been seen in people as young as 17, but symptoms do not generally begin appearing until years after the onset of head impacts, with early symptoms usually appearing in a patient's late 20's or 30's. Some common changes include impulse control problems, aggression, depression, and paranoia. As the disease progresses, some patients may ezperience problems with thinking and memory, including memory loss, confusion, impaired judgement, and eventually progressive dementia. Cognitive symptoms tend to appear later than mood and behavioral symptoms, and generally first appear in a patient’s 40s or 50s. Patients may exhibit one or both symptom clusters. In some cases, symptoms worsen with time (even if the patient suffers no additional head impacts), in other cases, symptoms may be stable for years before worsening.