How hypnic twitches reflect your nervous system’s response to letting go when you fall asleep or drift into hypnosis.
You’re lying comfortably, the day behind you, eyes closed, finally starting to drift off and then — suddenly — you jolt awake with a sharp twitch or the strange sensation of falling.
This curious experience, known as a hypnic jerk is a common part of the transition from wakefulness to sleep. While they are normally completely harmless they can be startling and annoying — and they are not limited to bedtime. People can also experience hypnic jerks when drifting into a hypnotic trance, particularly if they’re new to hypnosis or not used to relaxing deeply.
So, what’s going on?
The Body’s Little Panic Button
A hypnic jerk is a brief, involuntary muscle contraction that often occurs just as you're falling asleep. It may feel like tripping over something, a limb suddenly twitching, or a full-body jolt. People can also report vivid dream-like imagery — falling off a curb or missing a step — that seems to accompany the movement.
The most widely accepted theory is that as your nervous system begins to slow down, your brain misreads the muscle relaxation as a signal that you're falling. In response, it sends a burst of activity to “catch” you — an automatic jolt that might once have helped keep our ancestors from toppling out of trees while dozing.
This response is surprisingly ancient. Sleep science experts propose that hypnic jerks might be an archaic reflex, triggered as the brain mistakes muscle relaxation for falling, potentially a survival mechanism from tree-dwelling ancestors.
Hypnic jerks are also similar to the Moro reflex, a primitive startle reflex observed in newborns. When a baby feels as though they are falling or sense a sudden loss of support, their arms fling out, then retract in a protective motion. This reflex typically fades within the first few months of life, but the hypnic jerk, like the Moro reflex, may speak to a deeper instinct for safety and orientation.
The Connection to Hypnosis
Interestingly, this phenomenon doesn’t just happen as you fall asleep. It can occur when someone is entering a trance state in hypnosis, too, particularly in their first session, when the experience is unfamiliar and the body is still learning how to relax in a new context.
Hypnosis involves moving from alertness into a state of focused, relaxed awareness. Like drifting off to sleep, it involves a shift in brainwaves, slower breathing, reduced muscle tone, and a quieting of mental chatter. If the nervous system isn’t used to such stillness, it may respond with a sudden twitch.
I’ve occasionally had clients experience this in session. It tends to happen when someone feels a bit of resistance or uncertainty about being hypnotised, or when they’re simply stressed or overstimulated. For many, it’s a novel way to give themselves permission to switch off, so the body has to learn how to do it.
It happens to me too
I know I’ve experienced hypnic jerks at night during more stressful chapters of life. If I have big worries or significant events on my mind, I’m definitely more prone to them as I fall asleep, as though my body is hypervigilant, not quite ready to surrender to rest. I’ve also noticed them when I’m very tired but in a setting where I shouldn’t be drifting off, like in a long meeting (oops, embarrassing confession) or on a train. That inner conflict between fatigue and alertness seems to trip the same wire.
What Might Trigger Hypnic Jerks?
While they’re very common, some people are more susceptible to hypnic jerks than others. Contributing factors include:
Stress and anxiety, as the nervous system struggles to shift gear
Sleep deprivation, when the body tries to fall asleep too fast, creating misfires
Caffeine or stimulants, which keep you wired, even when you're trying to relax
Late-night screen time or intense exercise, both of which can overstimulate the brain and body
Worrying, overthinking or planning in bed all keep the system on alert.
In other words, the more tightly wound your system is, the more likely it is to fire off a reflex when you finally start to let go.
Learning to Let Go
If you’ve experienced hypnic jerks during sleep or while drifting into hypnosis, rest assured it’s normal. In fact, it can be a sign that your nervous system is transitioning, learning to shift into rest and safety.
Over time, as your body becomes more familiar with what it feels like to relax — whether through sleep, meditation, or hypnosis — these twitches often fade. The more we practise calm, the more easily we can enter it.
And let me give you a hypnotist’s insider trick: you can use the sensation to deepen your relaxation in a form of self-hypnosis. Next time you twitch just as you’re dozing off or
gently sinking into a trance, you might simply notice it, smile, and think:
“There it is — the moment I let go.”
Sleep tight!
This article is for informational purposes only and is not intended to replace professional medical advice, diagnosis, or treatment. If you have concerns about your health or experience frequent or severe hypnic jerks, please consult a qualified healthcare professional.
