Welcome to brain Stuff from house stuffworks dot com where smart happens. Hi Marshall Brain. Have you ever gotten up from your chair or woken up in the middle of the night and discovered that one of your arms or legs is falling completely asleep? What causes that? Most of the time when something falls asleep, it happens because your position squeezes some nerves. The pressure causes the nerves to stop sending signals, so your brain can't control any of
the muscles, and you also can't feel a thing. Once you remove the pressure, you don't regain feeling right away. There's a certain amount of readjustment time before the nerves can transmit impulses correctly. Again, some nerve cells don't transmit any information, and others start sending impulses erratically. This causes
that strange tingling sensation. Motor control fivers are thinner than the ones carrying touch information, so you can often move the body part before you've regained complete feeling in it. If you'd like to learn more about this and thousands of other topics, come to how Stuff works dot com. Be sure to check out our new video podcast, Stuff from the Future. Join how Stuff work staff as we explore the most promising and perplexing possibilities of tomorrow. The
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