Why do you twitch as you fall asleep? © Getty Images

Why do you twitch as you fall asleep?

When dreaming stops you sleeping... all sorts of odd brain activity and bodily responses can occur.

Asked by: Anonymous

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Twitching is a type of ‘myoclonic jerk’, an involuntary spasm in which some of your muscles quickly contract and relax again. It’s also called a ‘sleep start’, ‘hypnic jerk’, or ‘hypnagogic jerk’ and occurs during the interesting transitional state between waking and sleeping, when all sorts of odd experiences can occur.

The jerks are sometimes associated with dreams of flying or falling and some people report twitching as they hit the ground in a falling dream. Others report out-of-body experiences on the verge of sleep, abruptly ended with a sleep jerk.


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