Does shaking your head hurt your brain?

Just look at Muhammad Ali. He's taken so many punches in his life, that it's jiggled his brain just a little too much. He slurs his speech; he can barely walk.

Ok, I'm not taking any punches or anything, but he only fought, what, once a month or so. Let's say once a week with practice (but then he was probably wearing padding) and that was only what 10, 20 years. But, every day I get out of the shower and shake my hair! (That way I don't have to towel dry)

The problem is: am I destroying my brain in the process? What's going on up there as I jiggle around my gray matter? Am I losing irreplaceable neurons?

Even worse, would I notice?!!

However, a concussion occurs when you undergo a non-penetrating blow to the skull. This can be very dangerous. It is because your brain acts like a passenger in a car accident: The skull moves violently, and crashes into the brain. If this happens hard enough, you can undergo some irreparable damage.

So, if you shake your head hard enough to whack your brain into the side of your skull, then yes, you can damage it. If you shake your arm hard enough, you can dislodge it from its socket. Moderation in all things.

That said, I have indeed noticed that my head hurts after a hard shaking, and it has caused me some concern.