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YOU’RE DRIFTING OFF to sleep, inching ever closer toward dreamland, when all of a sudden you sense danger. You feel yourself falling, try to catch yourself and jerk abruptly awake.
What’s going on? You’ve experienced a common sleep disturbance known as a hypnic jerk. (The same thing is sometimes called a hypnagogic jerk or a sleep start, and they don’t always wake people up.)
“Nobody knows for sure what causes them,” explains psychologist Tom Stafford at BBC Future, “but to me they represent the side effects of a hidden battle for control in the brain that happens each night on the cusp between wakefulness and dreams.”
In other words, when the effects of sleep are just beginning to take over your body and brain, your waking self seems to creep back in unexpectedly sometimes, startling you awake. Boo.
What We Know About Hypnic Jerks
Hypnic jerks are involuntary muscle twitches known as myoclonus. Hiccups also fall into this category.
These momentarily alarming sleep disturbances are a bit of a mystery. But there are some theories about why we experience them.
One is this aforementioned idea that there’s a kind of sleep-wake wrestling match in your brain.
“As sleep paralysis sets in, remaining daytime energy kindles and bursts out in seemingly random movements,” Stafford writes.
Hypnic jerks are the last gasps of normal daytime motor control.
Another theory is evolutionary, stretching back to our primate ancestors. Frederick Coolidge, a psychologist at the University of Colorado, has suggested that a hypnic jerk could be “an archaic reflex to the brain’s misinterpreting the muscle relaxation accompanying the onset of sleep as a signal that the sleeping primate is falling out of a tree.
The reflex may also have had selective value by having the sleeper readjust or review his or her sleeping position in a nest or on a branch in order to assure that a fall did not occur.
There is no evidence to support either of these theories, and research on the subject is scant. Sleep starts are common and harmless, and unlikely to shoot to the top of anyone’s research agenda anytime soon.
But scientists have observed that hypnic jerks are associated with a rapid heartbeat, quickened breathing, sweat, and sometimes “a peculiar sensory feeling of ‘shock’ or ‘falling into the void’”.
They are “benign”, a study in the journal Sleep Medicine notes, and frequently occur in people who are perfectly healthy. They are sometimes, though not always, “triggered by fatigue, stress, sleep deprivation, vigorous exercise, and stimulants like caffeine and nicotine”.
If you experience them constantly, or enough that you have developed anxiety or insomnia, you should talk to a doctor. But for most of the 70% of people who experience them, hypnic jerks are a moment of harmless fright and nothing more. Take some deep breaths, relax, and try to go to back to sleep.
If a patient is worried about their hypnic jerks, one review in the journal Chest notes, “reassurance that this is a normal phenomenon is all that is needed”.
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Anyone experience sleep paralysis ? That is truly scary s**t
And the more you try wake up the more your heart beats like fü€k
I get that sometimes. Freaky alright. I also get another one where, when running, I start to levitate. It feels mental.
Alien abduction Johnjoe
Out of body experience adrian
I get sleep paralysis about 4-5 times a year, nothing compares to it for frightening the life out of you. Luckily for me it only lasts about a minute. Seen a program on it recently and some people get it on a monthly basis and it can last 15-20 minutes with them !!!!
I experience it as a dream where someone is in danger and I need to shout to warn them or something similar – and no matter how hard I try I can’t shout or get any words out.
It jolts me back to being awake and sweating.
Do you experience ‘the intruder’ with your sleep paralysis? I’ve just been reading about it and am now totally freaked out
I get them from time to time, don’t really think to much about it, also fall back asleep straight away, but by Jesus do you get a jerk,
What’s the intruder ?
Sleep demons like an Incubus or Succubus. That feeling you get where you think an evil presence is in the room with you. It’s like a hallucination that sometimes comes with sleep paralysis.
Thanks for that Ronan, going to sleep in kids’ room now…
Usually sleep paralysis with comes with hearing voices and thinking someone was in the room…one time I taught someone was trying to rob my tv and was trying to shout as best as I could but nothing was coming out..best thing to do is just relax and control your breathing and you should be able to snap out of it ..
They’re at their worst when you’ve been on the lash all weekend. I once hypnagogiced so hard I nearly went out the window.
When you are lying in your bed and suddenly you drop your mobile on to your face.
Then its time to go to sleep…
I remember reading somewhere ( or maybe I just watched way too many episodes of House) that another theory is its your brain making sure your alive as when you fall asleep your breathing and heart rate reduce and sometimes your brain can’t distinguish the difference between dying and falling asleep. It sends a shock into your system to make you wake in case you are dying……..
Happened me a few times and my first panicked thought was ‘oh 5hit I’m dying’. Serious freak out.
Emily,
That was my understanding too almost.
I heard that as you move through deep sleep your heart rate can drop so low that it could stop and so the ‘emergency’ system sends a jolt through the system to wake you up.
Thus when you hear about people ‘dying in their sleep’ their emergency system unfortunately didn’t work well enough.
I like them. They can occasionally help end an otherwise dull day in an interesting and exciting manner.
This shit always happens to me on the bus
Likewise. I’ve had to apologise to fellow passengers several times.
Night terrors are another terrifying sleep disorder. My “terror” of choice is spiders. I actually ended up on crutches after one with a bad sprain, having jumped out of the bed to escape the hundreds of spiders crawling all over me. Had an MRI and discovered I had a brain. Good times!
Is there a name for a truly horrifying “dream” in which your teeth are twisting and breaking in your mouth and falling out ??
I could tell you but googling it would be better.
Anxiety?
I regularly have the dream about the teeth falling out . I looked it up in a ‘Dream’ book that a friend of mine had . It said that it is a sign of feeling insecure.
Apparently that’s called bruxism (teeth grinding in our sleep) I’ve had to have one of my front teeth repaired countless times because of this dream. Now my dentist wants me to wear a mouth guard while I sleep yuk
Similar happens to ppl with epilepsy while awake, called myoclonic jerks, gives u an awful hop.
Does anyone else go to the same place in their dreams? I go to the same train station. I know where I am in my dream n I know the lay out of the station n what stop I need to change at. But it not a place I’ve ever been to in reality.
I’ve been turning up there for years.
I have epilepsy fusha2020 and i have experienced those jerks you mentioned . They are very frightening .
@Fusha. I have some places in my dreams that do not exist but I know them so well from my scary night-time visits, that I can recall them even now when awake. Ah gosh. Now I wish that I had not read these comments.
Yeah Tony, it is brutal. Used to happen quite a lot when I was younger . Real haunting feeling . Usually happened after a weekend on the sauce:)
I used to get these a lot after working at height so maybe there’s something in the falling out of a tree theory.
Nearly everyone that read this article will have it happen to them tonight now since it’s on their mind, I actually don’t mind them, just tells me that the ticker is still working,
If you have a falling dream and you actually hit the ground you will wake up dead!
As in….the undead?
Naw. I had a falling dream and hit the ground. The next part of the dream, I was walking down the hill where I was raised as a child.
Used to have a problem waking up. I would wake up in the dark and couldn’t move then I would get a feeling some one was lurking in the room and realise that I hadn’t actually woken up and wake up again and try and turn the light on and it would not switch on . The same sinister presence and then I would wake up again .. This would loop about half a dozen times when I would finally really wake up switch the light on . You can guarantee that I would leave it on for rest of the night..freaky..
That’s the freakiest I get that too mainly when im anxious about something, then when you do really wake up and turn on the light you wonder for a few minutes if your still dreaming lol
Had a couple of those. Heard them called night starts though.
Supposed to down to stress or worry about something.
Ohh the night paralysis NOT NICE
Always feel theres someone in the roon & u cant move a muscle, worst one is u wanna scream with fright, and you cant, terrifying
No one has mentioned Exploding Head Syndrome…….honest to god it’s a real thing! Google it. It’s like the jerk but not physical. Just before you fall to sleep you hear a really loud noise like a door slamming or a gun shot or a metal bar clanging sound. It’s literally all in your head. Anyone else have it??
Always get this when I dream I am falling ! Pretty sure I’m gona have a heart attack with one when I’m old :(
Whahhh!!! Oh jaysus
I can jerk 5 or 6 times a night from a deep sleep…no falling feeling or dream just jump and awake…can happen while about to sleep too…can be annoying when it keeps happening…frightens be jays us out of my partner
Next time this happens try and keep your mind Alert and when your body enters paralysis imagine yourself leaving your body – google etheric projection and learn how your soul can leave your body and experience the most life changing moment you will ever have – it works – try it then comment
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