Sleep paralysis is the muscle shutdown of dreaming sleep left running for a few seconds after your mind has woken up. You are conscious, you can usually open your eyes, and the rest of your body will not answer.
It is common, it ends on its own, and it is not a sign that anything is wrong with your mind. Roughly 7.6 percent of people in the general population have had at least one episode. [sharpless-prevalence]
Why you cannot move
During dreaming sleep your brain actively paralyses most of your skeletal muscles, and sleep paralysis is that system failing to switch off on time. The paralysis exists so that you do not physically act out whatever you are dreaming, which is a genuinely useful safeguard for anyone who has ever dreamt of running.
Waking is not a switch, it is a sequence. Consciousness can return before the muscle system has been released, and for a few seconds the two states overlap. The muscles that move your chest are driven separately, which is why breathing continues normally even when it does not feel like it.
Why people see something in the room
The presence is dream imagery that has carried on past the point of waking. You are awake enough to know you are in your own bedroom, which is exactly what makes the image so convincing: the brain is not inventing a dream landscape, it is adding a figure to a room you can genuinely see.
The details are strikingly consistent across the world and across centuries: a weight on the chest, a figure at the door, breathing that is not yours. Cultures have given it different names and different explanations. That the experience repeats so precisely among people who have never heard of each other is the clearest evidence that it is generated by the sleeping brain.
How common it is
Sleep paralysis is far more common than most people who have had it assume, and the belief that it is rare is part of what makes a first episode so frightening.
A schematic of the pattern reported in Sharpless and Barber's systematic review, drawn for this article rather than reproduced from it.
The review behind those figures aggregated more than 36,000 participants. [sharpless-prevalence] The student figure is the one worth holding on to, because students are also the group with the most irregular sleep, which is the strongest clue about what drives it.
What makes an episode more likely
Disrupted sleep timing is the association that appears most consistently, alongside insufficient sleep, high stress and sleeping on your back. [denis-variables] These are conditions rather than causes, and none of them guarantees an episode.
The practical version of that list is short. Nights that vary in length or timing, shift work and jet lag, periods of high anxiety or post-traumatic stress, and the supine position all raise the rate. Some substances and some medications do too, which is worth mentioning if episodes started when a prescription did.
Does this sound like your sleep?
These are the conditions most often present around an episode. Tick anything true of the last month.
0 of 6 ticked
Your sleep pattern contains most of what the research associates with episodes. That is encouraging rather than alarming, because sleep timing is something you can change.
A couple of the common associations are present. Regularising your sleep timing is the change with the most evidence behind it.
Little here points at the pattern most associated with episodes. If they are still happening often, it is worth raising with a doctor.
How to stop an episode while it is happening
Stop trying to move your whole body, and move something small instead. Straining against the paralysis is the instinctive response and it is the wrong one, because the effort raises panic without releasing the muscles any sooner.
Three things help. Breathe deliberately and normally, since your breathing muscles are unaffected and proving that to yourself removes the worst of the fear. Move your eyes, a finger or a toe, because small peripheral movements tend to come back first and often break the rest. And name what is happening while it happens, even silently: people who know what sleep paralysis is find episodes markedly less frightening than people who think they are being attacked.
How to have fewer episodes
Fix the sleep schedule before anything else, because irregular timing is the factor most consistently linked to episodes. [denis-variables] Consistent bed and wake times, across weekends as well, does more than any technique applied during an episode, and the wider case for it is in our pillar on sleep and mental health.
After that: get enough hours rather than the minimum you can function on, and try sleeping on your side if you currently sleep on your back. If you have been dreading bed since your first episode, that dread is worth treating directly, because it shortens sleep and shorter sleep produces more episodes. The loop closes quickly and it opens just as quickly.
When to seek help
Speak to a doctor if episodes are frequent, if they are accompanied by sudden daytime sleepiness, or if fear of them is now shortening your sleep. Frequent paralysis alongside overwhelming daytime sleepiness or sudden muscle weakness triggered by emotion is the combination that can point to narcolepsy, and that is worth assessing properly rather than waiting out.
It is also reasonable to seek help simply because it frightens you. Isolated sleep paralysis is harmless in itself, but the anxiety that builds around bedtime is treatable and does not resolve on its own. If a new medication coincided with the episodes starting, say so, because that is a detail a doctor can act on quickly.
How MyFreud can help
MyFreud tracks your sleep timing and mood together, which is what turns “I think my sleep has been bad” into a pattern you can see across weeks. Since irregular timing is the factor most strongly associated with sleep paralysis, seeing your own schedule laid out is often the fastest route to changing it.
Download MyFreud and start today: App Store or Google Play.