Hypnic jerk

Have you ever been drifting off to sleep and suddenly felt as if you were falling, then quickly jolted awake? That feeling is called a hypnic jerk.

So, when you're getting ready to sleep, your body starts to relax and your brain starts to slow down. Sometimes your brain thinks that you're falling or in danger, even though you're actually safe and still in bed. So, it sends a message to your muscles to quickly wake up and protect yourself from danger. This makes your arms or legs quickly jerk, jolt or twitch.

It might feel scary, but it’s actually a normal and natural process that happens to most people as they fall asleep. Plus, it's nothing to worry about - it won't hurt you or harm you in any way!