Repeated brain injury is cumulative in consequence and now has been linked to dementia later in life. But because the individual assaults are mild, players, soldiers, coaches, and medics alike can easily miss their significance.

"People -- especially those who played sports in high school -- will say, ‘yeah, I’ve had two or three concussions; what difference does it make?’” says neurosurgeon Gerald Grant, MD. “But after five mild brain injuries, permanent brain damage may have already occurred.”

Early Injuries Lead to Later Cognitive Deficits

For young people, brain injuries can lead to significant deficits in cognitive function, which sometimes don’t present themselves until well after the accident -- a middle-school athlete might suffer a concussion, seem to recover, and two years later start failing classes in school.

A Little Rest Goes a Long Way

Making sure that patients understand what “rest” means is important, says Grant. In the aftermath of a concussion, the patient should avoid physical exertion but also mental exertion -- that means no homework, no video games, no multitasking, no stress.

That’s a tall order in today’s world, but critical to allow the brain to recover.

Return-to-play guidelines have been established but are not well known among some physicians treating these patients. They can be found online through the American Academy of Neurology.