WEBVTT - Why do limbs fall asleep?

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<v Speaker 1>Welcome to brain Stuff from house stuffworks dot com where

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<v Speaker 1>smart happens. Hi Marshall Brain. Have you ever gotten up

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<v Speaker 1>from your chair or woken up in the middle of

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<v Speaker 1>the night and discovered that one of your arms or

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<v Speaker 1>legs is falling completely asleep? What causes that? Most of

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<v Speaker 1>the time when something falls asleep, it happens because your

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<v Speaker 1>position squeezes some nerves. The pressure causes the nerves to

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<v Speaker 1>stop sending signals, so your brain can't control any of

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<v Speaker 1>the muscles, and you also can't feel a thing. Once

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<v Speaker 1>you remove the pressure, you don't regain feeling right away.

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<v Speaker 1>There's a certain amount of readjustment time before the nerves

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<v Speaker 1>can transmit impulses correctly. Again, some nerve cells don't transmit

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<v Speaker 1>any information, and others start sending impulses erratically. This causes

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<v Speaker 1>that strange tingling sensation. Motor control fivers are thinner than

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<v Speaker 1>the ones carrying touch information, so you can often move

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<v Speaker 1>the body part before you've regained complete feeling in it.

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