So, have you found a new doctor to replace the concussion denier? This "no concussion unless you are knocked out" belief is very old and based on old wives tales and ignorance, if that can be.

I wonder if your doctor would let you hit him in the head with a baseball bat but not knock him out? With his logic of "no concussion unless knocked out," the baseball bat would not hurt him.

Julian Bailes, M.D. believes in the damaging effect of sub-concussive impacts. These are impacts that do not cause concussion symptoms but do have residual effects.

Here is part of an article that talks about sub-concussive blows.

http://abcnews.go.com/Nightline/rese...8838451&page=3