He left a note to send his brain for use in the ongoing study of the effect of concussions and head trauma on depression and suicide.

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Electroshock therapy, the decades-old treatment of last resort for depression, indiscriminately blasts the entire head to induce seizures and jar patients out of their blues.

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The report showed Seau had CTE, a brain disease linked head trauma, which can lead to depression.

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Quick wrote the book having himself worked with mental health patients, particularly those with head traumas, and having experienced deep depression himself.

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In both cases, Easterling and Duerson exhibited symptoms of repetitive head trauma: memory lapses, anger and deep depression, according to family and friends.

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As he probably suspected, the research revealed he had the type of head trauma from repeated hits that can lead to depression, which can lead to suicide.

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