February 16, 2010 Concussions from a bump on the head used to be no big deal.

"People just kind of said 'oh, that athlete got his bell rung' and didn't think much of it," says Dr. James Eckner of the University of Michigan's medical school.

That was then. Now experts worry about the cumulative damage from "mild" brain injury, especially among young athletes.


http://www.npr.org/templates/story/s...ryId=123761643