Why your body jerks when you are falling asleep - doctor explains all

Have you ever wondered why you sometimes jolt awake just as you’re beginning to fall asleep? A doctor has explained why and it could date back to an “ancient survival reflex”.

Dr Amir Khan took to Instagram on Sunday (21 September) to explain the sensation known as hipnic jerk, which takes place when you’re dozing off.

“As you drift into sleep your muscles relax and sometimes your brain interprets that as falling. It’s a misinterpretation. So it sends a quick signal to your body to catch you and that’s why we twitch awake,” he said.

Dr Khan explained some scientists believe it was developed from when we used to sleep in trees, as a “sudden twitch might have saved us from falling”.

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