A minority of concussion/mTBI patients report symptoms lasting a month or longer, and it's these patients you're most likely to be seeing in civilian practice. Read this account of one soldier's more complicated recovery:
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A Flashlight Out of the Dark
"I found that connecting with others who 'got it' was my way to flip the switch, my way to get my hands on the flashlight — my flashlight out of that dark space."
The treatment of longer-lasting effects of concussion is described in the next section.