Symptoms and Signs of CTE Initial symptoms of chronic traumatic encephalopathy typically include ≥ 1 of the following: Mood disturbance: Depression, irritability, and / or hopelessness Behavioral abnormalities: Impulsivity, explosivity, and / or aggression Cognitive impairment: Memory impairment, executive dysfunction, and / or dementia Motor abnormalities: Parkinsonism, ataxia, and / or dysarthria There are two distinct clinical courses: Mood disturbances and behavioral abnormalities develop during young adulthood (eg, during the patient's 30s), and cognitive impairment develops later.