Sleep Paralysis Demon: A Rare Feature Of A Common Sleep Disorder

Medically reviewed by Melissa Guarnaccia, LCSW
Updated March 28th, 2025 by BetterHelp Editorial Team
Content warning: Please be advised, the below article might mention trauma-related topics that could be triggering to the reader. Please see our Get Help Now page for more immediate resources.

Sleep paralysis is a condition that can have adverse impacts on one’s overall sleep function. During some instances of sleep paralysis, a person can experience hallucinations of what is referred to as a “sleep demon.” These aspects can date back several millennia, with the earliest written records of this phenomenon going back to ancient Mesopotamia in 2400 BC. This article explores aspects of sleep paralysis, the phenomena of “sleep demons”, as well as ways to improve upon aspects of sleep hygiene. 

An elderly woman sits pensively on her couch, gazing into the distance.
Getty/Viktoria Korobova
Are you experiencing sleep paralysis?

What is sleep paralysis?

Sleep paralysis is a condition that occurs when someone wakes up and is unable to move their extremities such as their arms and legs. This condition mimics that of paralysis-type panic attacks, however, the person is asleep when they encounter them. Sleep paralysis can often be accompanied by hallucination. Each case of sleep paralysis may vary, ranging from isolated themes of sleep paralysis to more recurrent patterns of sleep paralysis episodes. 

Sleep paralysis and rapid eye movement (REM) sleep

Sleep paralysis tends to occur during rapid eye movement (REM) sleep. REM sleep is one of several stages of sleep that holds unique properties that contribute to the phenomena of sleep paralysis. 

What is rapid eye movement (REM) sleep?

REM sleep is a typical part of the usual sleep cycle. You have several sleep cycles at night: REM, core, as well as deep sleep. Your body will cycle between phases of these cycles during a night’s sleep. Each episode of REM sleep gets longer and longer, with the initial phases lasting only a few minutes and the last ranging for at least half an hour. 

Why is REM sleep associated with sleep paralysis?

A person tends to experience dream content during REM sleep cycles. Further, aspects of body functions like blood pressure, heart rate, breathing, as well as brain activity increase during REM sleep cycles. The eyes move rapidly behind the eyelids, while the muscles in the arms and legs are unable to move to prevent the person from acting out their dreams. 

During instances of sleep paralysis, a person wakes up during REM sleep and are unable to move their extremities. Sleep paralysis may result from a malfunction during the transition from REM sleep and waking. It tends to be more common during the morning hours, however, it can happen at any time of night. While this experience is benign, it does create a strong sense of unease within a person who experiences it. 

What is a sleep paralysis demon?

Since paralysis can occur during REM sleep, you may experience interruptions in your sleep cycles where your brain is still in a dream state. This can result in the brain interpreting something real as something else such as a vivid hallucination. The brain is very active during REM sleep cycles. Due to this, some individuals will experience hallucinations via auditory, tactile, or olfactory (smell) hallucinations. 

What a sleep paralysis demon may look like

“Sleep demons” are a common hallucination during sleep paralysis. These are generally hallucinations of an intruding presence, whether this presence is in the room or a feeling of pressure on the chest while experiencing an aggressive act. 

These demons can result in the brain misinterpreting something it sees in the sleep area, such as a cat or a pile of clothing. During other instances, there may purely be sleep hallucinations. When these hallucinations occur upon waking, they are referred to as “hypnopompic hallucinations.” 

Why do I experience sleep paralysis?

Sleep paralysis varies and tends to affect each person differently. Some may experience a single incident, whereas others may have recurrent sleep paralysis episodes. Researchers aren’t entirely sure of causes; however, they posit some theories that could contribute to this condition. 

A man sits at the edge of his bed, holding his coffee while staring off into the distance.
Getty/Dean Mitchell

Causes of sleep paralysis

Some sleep habits that may contribute to sleep paralysis may include: 

  • Lack of sleep or sleep disruptions
  • Sleep disorders, like sleep apnea or narcolepsy
  • Shift work with work hours that change often and prevent a regular sleep schedule
  • Sleeping on your back
  • Mental health conditions like post-traumatic stress disorder, mood-related disorders (such as bipolar disorders), or anxiety disorders
  • Substance use

Risk factors for sleep paralysis

Some risk factors for sleep paralysis include poor sleep quality, anxiety disorders, alcohol consumption, and exposure to traumatic events. Research also shows that sleep paralysis may also have a genetic link as it can run in families.

What does sleep paralysis feel like?

Each person’s experience of sleep paralysis varies. In some instances, individuals may experience fear due to being awake but being unable to move their limbs. Some experience some paranoia due to feeling as if a sleep demon is watching them, while others may feel like something is sitting on their chest or choking them.

History and folklore of sleep demons

Sleep paralysis and sleep demons are not a modern phenomenon. Accounts of these experiences go back millennia, with different cultures coming up with their own folklore about sleep demons.

  • Mesopotamia: Some of the earliest records of sleep demons date back to 2400 BC in Mesopotamia and referred to a female demon known as Lilitu.
  • Europe: In Europe in the Middle Ages, the term “nightmare” was used to describe a supernatural entity that was usually female that sat on a person’s chest in an attempt to suffocate them.
  • Brazil: In Brazilian folklore, a pisadeira was believed to be an old woman who waited on rooftops and walked on the chests of people who slept on their backs with a full stomach.
  • Newfoundland: In the 1970s, people in Newfoundland called the sleep demon “ag rog” and believed that it caused pressure on the chest and paralysis.
  • Cambodia: Cambodian refugees described sleep paralysis as “khmaoch sângkât” and believed that a supernatural being pushed on the sleeper’s chest.

Diagnosing sleep paralysis

Sleep paralysis can be confirmed through both a physical and sleep exam. A doctor may ask you about your conditions, patterns of sleep, your energy levels throughout the day, medical history, medication history, as well as mental health history. They may also ask if you have any known family history of sleep paralysis. 

If your doctor has suspicions that an underlying sleep disorder is contributing to sleep paralysis, they may encourage you to undergo a sleep study. This will allow researchers to view your heart rate, brain activity, as well as breathing. 

Does everyone with sleep paralysis experience a sleep demon?

Not everyone who experiences sleep paralysis also experiences a sleep demon. About 75 percent of people with sleep paralysis experience hallucinations that are commonly perceived as sleep demons. 

Treating sleep paralysis

Treating sleep paralysis typically depends on the cause. Some possible treatments may include taking medications that prevent you from entering REM sleep or treat an underlying sleep condition or mental health disorder. 

Improving sleep hygiene can also help. Some tips for improving sleep hygiene can include:

  • Establishing a regular sleep schedule by going to bed and waking up at the same time every day
  • Creating a bedroom environment conducive to sleep by keeping it cool, dark, and quiet
  • Doing something relaxing before bed, like taking a bath or reading a book
  • Avoiding alcohol and large meals before bedtime
  • Avoiding caffeine in the afternoon and evening
  • Maintaining a regular exercise routine
  • Avoiding screens before bedtime

Can you stop sleep paralysis? 

Unfortunately, there aren’t ways to stop an episode of sleep paralysis, however, you can try to focus on making small body movements such as wiggling your toes. Attempts to get the body moving may result in the episode being shorter. 

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Are you experiencing sleep paralysis?

How psychotherapy can help

Sleep paralysis can be associated with some mental health conditions, like post-traumatic stress disorder, bipolar disorders, or anxiety disorders. It can also be an uncomfortable experience that can lead to anxiety disorders or diminished sleep quality. 

Psychotherapy can be beneficial for people who experience sleep paralysis as it can help address underlying mental health conditions that may be contributing to symptoms, as well as learn relaxation techniques to encourage restful sleep.Do you experience sleep paralysis? Consider online therapy

If you experience sleep paralysis, consider an online therapy platform like BetterHelp. Sleep paralysis and the conditions that may contribute to it can interrupt your sleep, which can leave you feeling tired. With BetterHelp, you can work with a professional therapist from the comfort of your own home without worrying about commuting to and from an office. Many people who sign up can be matched with a therapist in as little as 48 hours, so you can get started soon. Research has found that online therapy can be an effective treatment for many of the mental health conditions associated with sleep paralysis, including anxiety and PTSD. One meta-analysis concluded that improvement from video-delivered psychotherapy “is most pronounced when CBT is used, and when anxiety, depression, or PTSD are targeted” and that “therapy is no less efficacious when delivered via videoconferencing than in-person.”

Takeaway

Sleep paralysis is fairly common, with about 10% to 20% of people experiencing it at least once. While not all of these people will experience a sleep demon, about 75% will experience some form of hallucination. Sleep paralysis can be unnerving, as it can impact your ability to get a proper amount of rest. Working with a therapist can help you learn to manage any conditions that may be contributing to sleep paralysis and learn relaxation techniques to help you get a good night’s sleep.
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