When characters in books or movies get whacked on the head, they’re out like a light. (Or, if it’s a cartoon, they see little stars swirling around their head before everything goes dark). A bit later, they often wake up and ask some version of, “Where am I?” It's practically cliché in fiction, but it’s actually a pretty good description of what happens when you get a real concussion.
A concussion is a mild traumatic brain injury. That sounds scary, but pay attention to the word mild. According to Sean D. Hollis, a specialist in brain injury at the University of Alabama at Birmingham, that’s what defines a concussion. “Concussion is really just a mild form of a traumatic brain injury,” he says.
