Why Is Sleep Paralysis So Terrifying?

“I can’t move my body. My body is unconscious and my body is sleeping, but I am awake,” says Nuriman Tjiptarto, a 25-year-old IT project manager. “It just doesn’t feel right. There was once a time where I tried to scream, but nothing was coming out. It happened twice that same night — I had tried to wake up and move my body multiple times. I was like, Fuck, am I just stuck here? It feels like limbo; you can’t do anything about it.”

What Tjiptarto is describing is called sleep paralysis. The phenomenon plagues plenty of us: According to a 2011 study published in Sleep Medicine Reviews, 7.6 percent of the U.S.’s general population has experienced sleep paralysis at least once.

In some cases, a sleep-paralysis sufferer will see a shadowy or demonic figure. For 31-year-old Hadler da Silva, a senior safety adviser at Columbia University’s research labs, his coat rack would transform into a demon during regular sleep paralysis experienced in the early months of COVID lockdown. “I would see something with eyes even though it wouldn’t be defined,” he remembers. “It just felt like a figure. You just kind of stare at it until you go back to sleep or you’re out of it.

In other cases, it’s not quite so dramatic (but still pretty terrifying): Tjiptarto has never seen any figures, though she did once feel an “ominous energy” in the corner of the bedroom. “I was like, I know sleep demons exist, and I don’t want to encounter one, so I just did not look over there and I tried to force myself to go back to sleep,” she says. Spooky!

So what is sleep paralysis exactly, and is there anything we can do to prevent or stop it? Why do so many people see demons? To answer these questions and more, we spoke to a few experts and several sleep-paralysis sufferers about the haunting experience.

What is sleep paralysis?

“In a nutshell, sleep paralysis is the experience of either going to sleep or waking up and finding yourself completely unable to move,” says Brian Sharpless, a licensed clinical psychologist and the author of Monsters on the Couch: The Real Psychological Disorders Behind Your Favorite Horror Movies. “It’s not like you’re tired or your limbs feel heavy; you can’t move anything except for your eyes. Most people will be able to open their eyes, and you might have some control over your breathing, but that’s not a given.” Most people experience it as feeling consciously awake but paralyzed and unable to move, though it’s possible to remember it differently, a phenomenon Sharpless calls “sleep-state misperception.” For Meredith, 29, it was more like a frightening, recurring dream. “It was ultrarealistic, and the general theme would be someone entering my room,” she recalls of the sleep-paralysis episodes she frequently went through in college. “I would feel the bed move, like they were climbing in. It was really scary. I think I had that same dream five to ten times. I remember everything in detail: the feeling of the bed moving and the shadow, being like, Oh my God, I can’t move any of my limbs.”

Bindu Bansinath, a staff writer at the Cut, also remembers experiencing sleep paralysis for the first time in college. “I was taking a glorious 26-minute nap between classes, and when I woke up in my twin XL, I realized I couldn’t move,” she says. The overwhelmingly negative experience still happens to her today, as recently as a few weeks ago: “Physically, it’s pretty unnerving; I was conscious but unable to move my limbs. I was trying hard to make some movement, but nothing happened. Not to be dramatic, but the first time it happened, I was like, This is demonic.”

For Jen Ortiz, the Cut’s deputy editor, sleep paralysis feels “like I’m under ten heavy weighted blankets and can’t move freely,” she says. “Emotionally, I’m on the verge of freaking out.” Visually, the most she has seen is a blurry haze that could be nothing, but that hasn’t made it any less scary or real: “Have you ever gotten too high and convinced yourself, Well, I’ve lost the ability to talk — this is my life now? It’s like that.”

So what is going on with the body exactly? Baland Jalal, a neuroscientist and researcher at Harvard’s Department of Psychology, says it all starts during the REM cycle of sleep, the period of deep sleep during which we typically have the most striking dreams. “We have certain chemicals, called glycine and GABA, in the brain stem. These will slide down the spinal cord, eventually paralyzing our entire body, during REM,” he explains. Because REM dreams are so vivid, the brain paralyzes us so we don’t hurt ourselves or our bedmates in our sleep. “What happens during sleep paralysis, then, is that sometimes you can start to become perceptually awake. This tells us, first of all, that these systems are separate. You have a paralysis system that paralyzes you, but then you have part of the brain, the frontal areas, the perceptual areas, that are responsible for higher-order thinking and sensory experiences. You have the coupling of these two systems, where you start to become mentally awake, yet your REM brain is still saying, ‘No, buddy. You’re still paralyzed. Remain in REM.’”

The third element, says Sharpless, is dream mentation, in which those dreams so typical of REM sleep spill over into your conscious mind while your body is paralyzed, often resulting in vivid hallucinations. “Alongside the paralysis, there is often accompanying extreme fear as well as a wide range of terrifying and bizarre hallucinations,” says Dan Denis, a psychology lecturer at the University of York. In fact, says Sharpless, the rate of fear jumps dramatically as compared to the more traditional nightmare. “Whereas normal dreams are only scary around 30 percent of the time there’s sleep paralysis, hallucinations are scary upwards of 80 or 90 percent of the time,” he says. “Most people do not have pleasant experiences with their hallucinations and sleep paralysis.”

What do you see during sleep paralysis?

As previously mentioned, sleep paralysis often — though not always — includes some amount of hallucination, usually involving a humanlike figure. In a 2019 study Sharpless conducted with a colleague, they found that 57.8 percent of participants “sensed a presence,” 21.6 percent hallucinated another person, and 24.3 percent hallucinated a nonhuman being. “We catalogued using two samples — one East Coast U.S., the other West Coast U.S. — of students, and we asked what they hallucinated. The most frequent hallucination of nonhuman beings were shadow people, like the Hat Man, Slender Man — things like that,” says Sharpless. “Next most common was ghosts. But if you look at some of the classic sleep-paralysis things like demons and aliens, there were very few. I’m guessing that represents some sort of cultural shift. If we were in 15th-century France, we might be seeing succubi or incubi.”

Jalal, too, has found in his research that sleep-paralysis hallucinations are strongly influenced by popular cultural contexts and narratives. “I spoke with a New Yorker about ten years ago, and her ghost was a burglar. It was somebody breaking into her house,” he explains. But in globally focused studies, hallucinations correlated to specific countries. “In Egypt, for example, we discovered that it’s a magic genie. In Italy, it’s something called the Pandafeche, which is a giant witch-cat. In Turkey, we discovered something called the Karabasan, which is also some kind of mysterious, ghostlike, demonic entity. In South Africa, we found that it’s something called the Tokoloshe demons. It’s a small dwarflike creature sent by a person that does witchcraft.”

You may also just see your usual surroundings. Bansinath remembers fixating on her immobile limbs (albeit with a dizzy, spinning quality to her vision), while Tjiptarto only ever saw the room she was sleeping in.

When does sleep paralysis happen?

Although it can happen at any time of night and is primarily connected to the REM cycle, sleep paralysis often happens in the morning, around the time you’d normally wake up. “I think most people experience it as they’re waking up, as opposed to going to sleep,” says Sharpless. But not always: For da Silva, sleep paralysis often happened in the very early morning as a sleep disruption. “I would wake up naturally, and it would be the middle of the night — 3 or 4 a.m.,” he says. The more common exception? Lucid dreaming, says Sharpless. “Sometimes attempts to lucid dream can lead to sleep-paralysis episodes that can be really, really scary for people.”

What causes sleep paralysis?

Sharpless says the list of lifestyle factors related to sleep paralysis is long, and studies on the subject have found many correlations but little direct causation. But genetics definitely play a role; he says colleagues of his found a mutation on the PER2 gene that can increase the likeliness of sleep paralysis. In a 2018 systematic review Denis worked on, he and his colleagues found that sleep paralysis was often associated with other sleep problems as well as “anomalous” sleep experiences like lucid dreaming, nightmares, and exploding-head syndrome. They also found that lifestyle could play a role: “Another factor was exposure to stress as well as symptoms of anxiety,” says Denis. “It’s possible that these factors relate to sleep paralysis through first disrupting sleep. Generally speaking, anything that disrupts your sleep may make sleep paralysis more likely.” Denis, Sharpless, and Jalal all mentioned alcohol as one common contributing factor. “Alcohol suppresses REM sleep, so while the alcohol is in your system, you’ll be less likely to dream,” says Sharpless. “But you get a rebound effect earlier in the morning, so once the alcohol is out of your system, you’re more likely to have REM sleep, which would make you more likely to have sleep paralysis as you awaken.”

Can sleep paralysis be prevented?

Clearly, sleep paralysis is pretty much always a terrible time, whether it’s simply uncomfortable or seriously blood-curdling. If you’re experiencing it regularly, there are preventive measures you can take. “One of the easiest things you can do is try to sleep on your side,” says Sharpless. “You’re most likely to have it when sleeping on your back and next most likely when you’re sleeping on your stomach.” He recommends having a partner roll you over or getting a sleep-position trainer. Other than that, it’s all about having good sleep hygiene: “Go to bed and wake up at the same time every day, even on the weekends. Try to get your insomnia treated, because sleep paralysis can be secondary to that. If you have any mental-health issues that might make sleep paralysis more likely, I would guess that, in a lot of cases, if you treat the depression or anxiety, the sleep paralysis will either go away or be minimized.” Sharpless also says there are medications and psychotherapy options you can try if the problem is persistent and detrimental to your life, so if you’re experiencing it often, talk to your doctor. Sleep paralysis can also be a symptom of narcolepsy (though it’s an extremely rare condition), so if it’s happening a lot, it’s worth asking about. But ultimately, says Sharpless, “it’s not harmful. It’s just a strange experience.”

Can you stop sleep paralysis while experiencing it?

In addition to the deterrent measures you can take, there are also techniques you can try to stop, or at least reduce the severity of, sleep paralysis as you’re experiencing it. Jalal says he developed a therapy called meditation-relaxation therapy, or MR therapy. In fact, the technique is Cut-tested and approved. Jalal says that we should exploit the few moments of conscious awareness we have when sleep paralysis strikes. First, he says, close your eyes “to avoid any sort of infiltration of your environment — because things in your environment can actually influence the hallucinations, too. A picture on the wall might turn into a monster.” Then it’s time for what he calls emotional and psychological distancing: “You tell yourself, It’s common all around the world. There’s no need to be afraid. It’s gonna go away. It’s not dangerous. It’s not permanent.”

The third step is to focus on something positive — whatever it is that powerfully resonates with you. “We don’t interfere with what it is,” says Jalal. “Prayer seems to help for a lot of people, too. Something that’s extremely powerful for you as a person, you focus on that. Your attention systems in the brain have limited capacity. You can’t really attend to many things at the same time. So you attend to these positive thoughts instead.” The fourth and final step? Relax your muscles, and avoid trying to “escape” or move your limbs. This can help prevent the sort of out-of-body experience that causes hallucinations.

If you do want to try moving, Sharpless recommends focusing on an extremely small body part. “In one of my studies from 2016, we asked people what they do to get out of it and how often it works, and that was by far the best thing,” he says. “So focus on moving your pinkie or a toe, maybe even your tongue, as opposed to trying to get your whole body to move. Now, whether that works to get you out of it quicker, or whether it distracts you from seeing the scary experiences, I’m not sure. But it does seem to help.”

Sharpless also recommends a similar mental-reframing practice like Jalal’s MR therapy. “Once you recognize that you can’t move, tell yourself, I’m having sleep paralysis. Try to have some humor with it. Try to reframe it as not a real supernatural event. What’s fascinating is that as soon as the paralysis abates, the hallucinations go away.”

Tjiptarto’s tried-and-true method? Going back to sleep. “Once I realize I can’t move, I’ll be like, Oh damn, I’m in sleep paralysis,” she says. “That’s usually the thought I have. Like, Not this again. Then I will try to force myself to go back to bed. I’m not trying to see anything scary; I’m not trying to be in sleep paralysis for too long. I try to go back to sleep and then once I go back to sleep and I actually wake up, I try to move my body to know I’m actually awake.”

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