"There's growing evidence that a physical injury to the brain can make people susceptible to post-traumatic stress disorder.
Studies of troops who deployed to Iraq and Afghanistan have found that service members who have suffered a concussion or mild traumatic..."
http://www.npr.org/sections/health-shots/2016/09/26/495074707/war-studies-suggest-a-concussion-leaves-the-brain-vulnerable-to-ptsd?utm_medium=RSS&utm_campaign=world
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