# Is my brain bouncing in my skull?

**URL:** <https://boards.straightdope.com/t/is-my-brain-bouncing-in-my-skull/232125>\
**Category:** Factual Questions\
**Created:** [March 2, 2004, 4:40pm UTC](https://boards.straightdope.com/t/is-my-brain-bouncing-in-my-skull/232125 "2004-03-02T16:40:13Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![istara](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@istara](https://boards.straightdope.com/u/istara)\
**Post date:** [March 2, 2004, 4:40pm UTC](https://boards.straightdope.com/t/is-my-brain-bouncing-in-my-skull/232125/1 "2004-03-02T16:40:13Z")

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I have one of those small exercise trampolines which recently I decided to try using again.

But when I jump on it, it feels like something shakes within my head. I am worried this is my brain moving in its jelly sac(?) - seriously. Could I be doing damage to my brain by using this trampoline? I am not jumping (IMO) particularly hard or high.

Anyone with experience of these things please advise!

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**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\
**Post date:** [March 2, 2004, 5:14pm UTC](https://boards.straightdope.com/t/is-my-brain-bouncing-in-my-skull/232125/2 "2004-03-02T17:14:31Z")

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Your brain can move around a bit inside the fluid cushion in your skull. When it bangs around too much you can get a concussion, a brain bruise which is serious. What you are probably feeling is your scalp shifring on the _outside_ of your headbone. Try this experiment, grab your hair and shift your scalp front to back. Do you get the same sensation?

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**Author:** ![istara](https://avatars.discourse-cdn.com/v4/letter/i/e79b87/32.png) [@istara](https://boards.straightdope.com/u/istara)\
**Post date:** [March 2, 2004, 6:31pm UTC](https://boards.straightdope.com/t/is-my-brain-bouncing-in-my-skull/232125/3 "2004-03-02T18:31:32Z")

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I just tried the hair thing and the trampoline thing again, and no, I don’t think so. Every few jumps (maybe every four) there is a more painful thud feel inside my skull.

I find it hard to believe that a trampoline could cause brain issues, given these things are so widespread. It would have been a health scare long before now.

OTOH I know that things like boxing cause the brain to get swished around in its sac.

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**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\
**Post date:** [March 2, 2004, 7:46pm UTC](https://boards.straightdope.com/t/is-my-brain-bouncing-in-my-skull/232125/4 "2004-03-02T19:46:12Z")

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That doesn’t sound good. I’d consider asking your doctor about it. In any event even though a trampoline shouldn’t give a hard impact you might want to stay off of it. Also don’t take up headbanging as a hobby.