Just one concussion can cause someone to go on and commit a violent crime.
New AUT research shows even a mild traumatic brain injury significantly increases the risk of criminal behaviour over the following decade.
It also exacerbates mental health difficulties, drug abuse and managing emotional reactions to events.
Researcher Gail Pacheco told Kate Hawkesby a concussion can result in more criminal convictions and court charges later in life.
She says the risk is higher amongst men and those who have had multiple brain injuries.
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