Why do you jolt awake just as you fall asleep?
That falling feeling followed by a jolt, just as you drift off, has a name: the hypnic jerk. This Short explains in twenty seconds what it is, and what tends to make it more likely.
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Made with AI. Parts of this video are AI-generated (see “How this was made” below).
What it says
A hypnic jerk (also called a sleep start) is a sudden, brief twitch of the muscles that happens as you cross from wakefulness into sleep. It can come with a feeling of falling or a flash of a dream, and it can be strong enough to wake you. According to the Sleep Foundation, they are very common and generally harmless, and stress, tiredness and a lot of caffeine can make them more likely.
If they keep waking you
Small changes can make the edge of sleep calmer: an earlier last coffee (our caffeine cutoff calculator suggests a time for your bedtime), a wind-down that lets the day settle, and a steady, quiet sound so small noises don’t startle you. A slow guided wind-down such as our guided sleep meditation for overthinking is the video this Short points to.
This is general information, not medical advice. If jolts are frequent, or come with other symptoms, talk to a doctor.
About these Shorts
Our “Why your body does this” Shorts explain one odd thing that happens around sleep, with the source listed below. There is no voice: the points appear as text over an AI-made picture of a misty lake, with a simple glowing line that jolts once. For another question people ask at night, see why you wake up at 3 AM.
Why it can feel like falling
Nobody knows for certain why hypnic jerks happen. One common idea is that, as your muscles relax at sleep onset, the brain briefly misreads the change as a fall and the body reacts. Whatever the cause, the jolt itself passes in a moment. If one wakes you, a long, slow breath out and letting your body go heavy again is usually all it takes to drift back.
Transcript
There is no narration. The on-screen text, in order:
Why your body does this
Why do you jolt awake just as you drift off?
It’s called a hypnic jerk.
A sudden twitch as your muscles let go at the edge of sleep.
Very common, and usually harmless. (Source: Sleep Foundation)
Stress, tiredness and lots of caffeine can make it more likely. (Source: Sleep Foundation)
How this was made
No voice. The misty lake is an AI-generated still image; the glowing line, text and soft pad underneath are made by SleepBetter.
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Sleep videos and guided relaxation are for general wellness, not medical advice. If poor sleep is affecting your days, talk to a doctor or a sleep specialist.