Sleep paralysis: waking up and unable to move. What happens, and what traditions say

You wake up and cannot move or speak. Sometimes you sense someone in the room, or feel a weight on your chest. It is frightening, but it is not dangerous: your body is still in the stillness of dream sleep while your mind is already awake, and it passes on its own, usually within seconds to a few minutes. This guide explains what happens, why, what helps during and after, and how cultures all over the world have given this same experience a name.

In short

In sleep paralysis you wake up but briefly cannot move or speak, sometimes with pressure on your chest or a sense that someone is there.
It is not dangerous: your body is still in the stillness of dream sleep while your mind is awake, and it passes by itself.
About one in thirteen people experience it, and more than one in four students.
Cultures worldwide have given this experience a figure, from the mare to kanashibari; see your doctor if it happens often along with extreme daytime sleepiness.

What sleep paralysis is

During REM sleep, the phase in which we dream most vividly, the brain sends a signal that keeps the large muscles still. That is a good thing: it stops you from acting out your dreams. Sleep paralysis happens when you become aware while that stillness is still switched on. Your mind is awake, your eyes can usually open, but your body does not yet respond.

What people experience is remarkably similar all over the world. You cannot move or speak. Many people feel pressure on their chest, as if something is sitting on it, and have the sense that they cannot breathe, even though breathing carries on as normal. Some hear sounds, a buzzing, footsteps, a voice. And many sense a presence: someone in the room, at the door, beside the bed. Sometimes that presence is seen, as a shadow or a figure. Researchers such as Allan Cheyne, who collected thousands of accounts, call these intruder experiences; they are among the most common features, and the most frightening.

Sleep paralysis can happen while falling asleep (hypnagogic) or while waking up (hypnopompic). An episode usually lasts from a few seconds to a few minutes, although it can feel much longer.

Cheyne and his colleagues found that the experiences fall into three groups that often appear together. There is the intruder: the sense of a presence, sometimes seen or heard. There is the pressure: the weight on the chest and the struggle to breathe. And there are unusual bodily sensations: floating, spinning, falling, or the feeling of leaving your body. Knowing that these are typical parts of one and the same phenomenon helps many people to place what they went through.

It is common. A systematic review by Brian Sharpless and Jacques Barber in 2011 found that about one in thirteen people in the general population has it at least once in their life, and that among students the figure rises to more than one in four. Shift workers, people with irregular sleep and people under a lot of stress have it more often. Most have it a few times in their life; a smaller group has it regularly.

Is it dangerous?

No. Sleep paralysis in itself is not dangerous. You keep breathing the whole time, even when it feels as if you cannot, and the episode ends by itself. Nobody dies of sleep paralysis, and it does not damage your body or your mind.

The worst part is the fear. Not being able to move while sensing a presence is one of the most frightening things a person can experience at night, and it makes complete sense to be shaken by it. Knowing what is happening is often the biggest help: many people find that once they understand it, the next episode is far less frightening.

Nor does it mean that something is wrong with your mind. Isolated sleep paralysis, the kind that comes now and then without any other sleep problems, is common in healthy people of every age. It says something about how you slept, not about who you are.

There is one situation in which it is wise to see a doctor. If sleep paralysis happens often, and you are also extremely sleepy during the day, fall asleep suddenly at unexpected moments, or feel your muscles suddenly go weak when you laugh or are startled, mention it to your GP. Together these can point to a sleep disorder such as narcolepsy, which can be investigated and treated. That is a reason to have it checked, not a diagnosis.

Why it happens

Sleep paralysis happens when the boundary between sleeping and waking is a little blurred. Anything that disturbs your sleep makes that more likely. The best-known triggers are too little sleep, an irregular rhythm, shift work and jet lag, because they push REM sleep to unusual moments. Stress and worry play a part, as do some medicines and alcohol late in the evening. Many people notice that it happens most often when they sleep on their back; in research, too, that position comes up again and again.

People with anxiety, and people who have been through something traumatic, have sleep paralysis more often. That does not mean that everyone who has it is anxious; it means that a tense, alert body sleeps more lightly and wakes more easily in the middle of REM sleep.

It also seems to run in families to some extent: studies of twins suggest that part of the tendency is inherited. If a parent or sibling has had it, you are a little more likely to have it too, which is one more reason to talk about it at home.

Why the presence? Researchers think that the brain, in this strange state of being awake but unable to move, switches on its threat detection. A part of the brain that is always looking for danger finds a body that does not respond and a room that is dark, and it fills in the most obvious explanation: something is there. Because REM sleep is still partly active, dream images can mix with what you actually see, so the presence can look and sound real. The pressure on the chest is often explained by the stillness of the breathing muscles: breathing goes on, but it feels shallow and heavy.

That explanation does not make the experience less real. It explains why people in every culture and every century have told the same story, each in their own words.

The nightmare that is not a dream: where the word comes from

The English word nightmare, like the Dutch nachtmerrie, originally meant exactly this experience. The mare was a night spirit in Germanic folk belief that sat on the chest of a sleeper and pressed the breath out of them. In German, too, the word for nightmare, Albtraum, recalls the Alp, a similar figure. The French cauchemar comes from cauquemare: caucher, to press, and the same mare.

The best-known image of it hangs in a museum in Detroit. In 1781 the painter Henry Fuseli made The Nightmare: a woman lies asleep across a bed, a small demon squats on her chest, and a horse's head looks in through the curtains. It became one of the most famous paintings of its time, and it shows almost exactly what people with sleep paralysis describe: the sleeper, the weight on the chest, the presence in the room.

So for centuries the frightening experience of waking up under a weight had its own name, long before nightmare came to mean any bad dream. The old meaning has largely faded, but the experience has not. Our guide to nightmares covers the bad dreams themselves; here we stay with the moment between sleeping and waking, and with the stories cultures tell about it. That folklore is described here as folklore: as the way people have tried to understand something that really happens to them.

Sleep paralysis around the world at a glance

The same experience, told in different ways: what it is called, who or what people sense, and what they do.

Culture or tradition	What it is called	Who or what is felt	What people do
Netherlands, England, Germany	Nachtmerrie, nightmare, Alpdrücken	The mare or the Alp on the chest	Old folklore; today mostly explained as sleep
Newfoundland	Being hagged	The old hag	Telling it to others who know it
Islam	Al-jathoom, kabus	A presence, in folk belief djinn	Ayat al-kursi, the last surahs, the right side
Christianity	No single name	For some a spiritual attack, for others physical	Prayer, or simply better sleep
Winti and Suriname	Told in family terms	A spirit or ancestor asking attention; for some, fear of wisi	Discuss in the family or with an expert
Japan	Kanashibari	Being bound, a presence	Widely known; often seen as fatigue
Brazil	Pisadeira	An old woman who steps on the chest	Not sleeping on your back with a full stomach
Cambodia	"The ghost pushes you down"	A ghost or spirit	Seen as a spiritual matter in many families

Stories differ by family, region and time.

What traditions tell: Suriname, Islam and Christianity

In Surinamese and wider Caribbean families, sleep paralysis is often not seen as only physical. In Winti, an experience like this can be read as a sign that a spirit or an ancestor wants attention, or that something in the family is out of balance; experts in the tradition look at the person's situation and family before saying anything about it. Some people fear that harmful influence, such as wisi, or a bakru, is behind it. That is a fear some people carry, not something the experience proves, and it deserves to be listened to rather than dismissed. What it means for a family is decided within that family or with someone knowledgeable. Our guide to how Winti reads a dream explains the approach, and in Haiti and the wider Caribbean, too, such experiences are often linked with the spirit world, as our guide to Vodou and dreams describes.

In many Arabic-speaking countries sleep paralysis is called al-jathoom, the one who sits or presses down, and in folk belief it is often linked with djinn. Studies among students in Egypt found that many people there explain their episodes in that way. Islam describes djinn as real beings, but it does not say that every night experience is caused by one. What many Muslims do is protect their sleep through the Sunna: reciting ayat al-kursi before sleeping, reciting the last three surahs of the Qur'an, al-Ikhlas, al-Falaq and an-Nas, and lying down on the right side. The tradition describes these as practices of the Prophet, and many people say they find peace in them.

Among Christians, views differ. Some believers, especially in charismatic and Pentecostal churches, experience sleep paralysis as a spiritual attack and respond with prayer, sometimes simply speaking the name of Jesus in their mind. Others, in many churches, see it as a purely physical phenomenon that has nothing to do with faith. Both views exist side by side, and Dreamkin does not choose between them. Our guide to nightmares in the Christian tradition goes further into how Christians deal with frightening nights.

The same experience all over the world

What makes sleep paralysis so remarkable is that it appears in almost every culture, and almost everywhere it has been given a figure.

In Newfoundland, in Canada, people speak of being "hagged", visited by the old hag who sits on the chest. The folklorist David Hufford studied these accounts in his book The Terror That Comes in the Night, and showed that people who had never heard the story described the same experience in the same details. That was an important finding: the experience comes first, the story after.

In Japan the experience is called kanashibari, literally being bound as if by metal. It is so well known there that surveys by the Japanese researcher Kazuhiko Fukuda and colleagues found many students recognised it by name. In Brazil people tell of the pisadeira, an old woman with long nails who walks on the rooftops at night and steps on the chest of someone who has gone to sleep on a full stomach, lying on their back. In Germany the Alp pressed on the sleeper, which is why a bad night was once called Alpdrücken, Alp-pressing. Among Cambodian communities, researchers recorded the expression "the ghost pushes you down".

The figures differ, a hag, a spirit, a demon, a ghost, an old woman on the roof, but the experience they explain is the same: awake, unable to move, a weight, a presence. For readers that is often the most reassuring part of all. What happened to you is not strange or unique; people everywhere have known it for as long as stories have been told, and found words for it.

What you can do during sleep paralysis

The most important thing to remember is that it passes. However long it feels, an episode ends by itself, usually within a minute or two.

Try to breathe slowly and calmly. Your breathing is working, even if it feels heavy; slowing it down tells your body that there is no danger. Then try to move something small rather than your whole body. Wiggle a toe or a finger, move your eyes, or scrunch up your face. Small movements often break the stillness sooner than trying to sit up.

Many people find it helps not to fight the presence they sense. Struggling makes the fear bigger, while focusing on something else, a sound in the room, the feeling of the sheet, counting slowly, lets you wake up fully, and the presence fades as you do.

Some people use a prayer, a verse or a name from their own tradition: Muslims may recite ayat al-kursi in their mind, Christians may pray, and others say a word that means safety to them. That is something people do and find comfort in, not a technique Dreamkin prescribes.

If you share a bed, it can help to agree on a signal. Many people can make a small sound or move their eyes or breathing during an episode; a partner who notices that and gently touches you or says your name can help you wake up fully. Touch is often the quickest way out.

When it is over, turn on a light, sit up for a moment, and let your body wake up properly before you lie down again. If you fall straight back asleep in the same position, another episode is more likely.

How to prevent it

Because sleep paralysis happens when sleep is disturbed, the best prevention is a regular, sufficient night's sleep. Go to bed and get up at roughly the same times, also at weekends, and try to get enough hours. That alone makes a big difference for many people.

If you notice that it happens mostly when you sleep on your back, try sleeping on your side; a pillow behind your back can help you stay there. Limit alcohol in the late evening, and give yourself time to wind down before sleeping: less screen, less work, less news. If stress is behind it, anything that lowers stress during the day also helps at night.

Students, shift workers and new parents have it more often for one simple reason: their sleep is short and irregular. If that is your situation, protecting a few regular nights a week, and making up for short nights with a nap early in the afternoon rather than late in the evening, can already reduce how often it happens.

If episodes keep returning, it can help to write them down: when it happened, how you slept the nights before, what position you were in, and what you experienced. After a few weeks a pattern often appears, for example that it comes after short nights or busy days. Our guide to remembering your dreams explains how to keep a journal that is easy to maintain.

And tell someone. Many people keep sleep paralysis to themselves because they are afraid it sounds strange. Hearing that someone else has had the same experience is often the biggest relief.

When to look for help

See your GP if sleep paralysis happens often, if you are afraid to go to sleep because of it, or if it comes with extreme sleepiness during the day, sudden sleep attacks or muscle weakness when you laugh or are startled. Those are reasons to have your sleep checked, and help is available.

For people who have it often and are troubled by it, psychologists have developed forms of cognitive behavioural therapy aimed specifically at sleep paralysis: understanding what happens, practising what to do during an episode, and improving sleep.

If frightening nights come with thoughts of not wanting to live, do not wait: contact a doctor or a crisis line. In the UK you can call Samaritans on 116 123, in the US you can call or text 988, and elsewhere your local emergency number or crisis line.

Sleep paralysis and your dreams

Sleep paralysis also has a curious relationship with lucid dreaming, the experience of knowing you are dreaming while the dream goes on. Both happen on the border between REM sleep and waking, and some people who practise lucid dreaming describe slipping from sleep paralysis into a dream they can steer, or into the sensation of floating out of their body. For most people, though, sleep paralysis is simply something they want to have less of, and that is where better sleep comes first.

Sleep paralysis often comes in the same periods as vivid dreams and nightmares, and sometimes the dream just before it, or the images during it, stay with you. Write down what you experienced, as calmly and precisely as you can. In the Dreamkin app you can record your dreams in one private place, and over time your Dream Book shows which images and feelings return, and when they fade.