What causes sleep paralysis? Dark forces vs. sleep problems

By Vladimir Marchenko

  1. What is sleep paralysis like
  2. The types of sleep paralysis
  3. What causes sleep paralysis
  4. How to stop sleep paralysis
  5. How to prevent sleep paralysis

Sleep paralysis is one of the most serious sleep abnormalities that is characterised by a temporal inability to move or make any sound. Until recently, it was believed that sleep paralysis is caused by some frightening demons who come at night. However, modern medicine has its own opinion on sleep paralysis, based on scientific evidence.

What is sleep paralysis like

Ancient texts contain the first descriptions of the phenomenon of sleep paralysis. It was already known for ancient Egyptians, Scandinavian tribes, as well as the inhabitants of the Arabian Peninsula and Japan. Most often it was believed to be a night visit from an evil spirit (a demon, a witch, or a genie). In the second half of the 20th century, aliens were also included in the list of the possible causes. Thus, some dark vague entities were described to strangle a person, climb onto his chest and paralyze. Some individuals even claimed to make telepathic contact with such visitors.

A typical description of the sleep paralysis of the past looked like this:

“I wake up in the middle of the night, but I feel as if I am still half-asleep. I don`t know what to do during sleep paralysis. I try to say or shout something, but I can't. I can only slightly open my eyes, however, I can very clearly hear everything that is happening around. I'm scared, I try to get up and move but I can't. I begin to breathe deeper and in this moment it seems like someone is silently sitting on my chest or standing next to me. Sometimes “it” breathes, walks around and squeezes my chest. It does not allow me to move and paralyzes me. Sometimes it lasts seconds, sometimes  —  several minutes."

picture Nightmare by G. Fussli (1781)
The visit of the "demon" is depicted in the painting "Nightmare" by G. Fussli (1781)

Scientific studies indicate that at least 8% of the world's population has experienced sleep paralysis at least once. Up to 40% of people suffering from panic attacks experience something similar to sleep paralysis (SP). Although, it is different from a nightmare as during SP a person is completely conscious, retains the perception of what is happening around, however, may experience auditory and visual hallucinations and stiffness in movements. Sleep paralysis terminates as soon as the full awakening occurs, or from the actions of another person.

The types of sleep paralysis

There are two types of sleep paralysis:

  • semiconscious, or hypnagogic  —  happens during falling asleep, usually, on the border of wakefulness and sleep. The inability to move causes fear;
  • hypnopompic - is observed at night. Muscle dysfunction occurs upon awakening.
how scared about sleep paralysis
The results of the nosleeplessnights.com survey show how fearful the experience of sleep paralysis is for people who participated in the survey

The sensations that people have during the manifestation of sleep paralysis are divided into at least three categories:

1. "The presence of a stranger." Similarly to “a demon coming at night”, in this case, people experience auditory, visual, and sometimes motor hallucinations as if there was a stranger in the room.

2. "Physical contact." It manifests as chest compression, difficulty breathing, and pain. Usually, people imagine some entities that have climbed on top of them which threaten their safety.

3. "Out-of-body experience." It feels like falling, flying, soaring, and being "out of the body". In this case, patients often believe that they are dying or abducted by aliens.

What causes sleep paralysis

SP is caused by several reasons which are often associated with mental disorders. For example, a study held in 2012 showed that sleep paralysis commonly occurred among patients with panic disorder (34.6%), psychiatric patients (31.9%), and students (28.3%).

What triggers sleep paralysis

  • Stress;
  • Irregular sleep;
  • Insomnia;
  • Post-traumatic stress disorder;
  • Narcolepsy;
  • Panic attacks;
  • Hypertension;
  • Bipolar disorder;
  • Sexual abuse;
  • Schizophrenia;
  • Taking certain groups of medicines;
  • Bad habits;
  • Sleeping on your back;
  • Genetic predisposition, etc.

Some studies indicate that people with obstructive sleep apnea (a condition that is characterised by the interruption of breathing during sleep) are more likely to experience sleep paralysis. Same was demonstrated for people with nocturnal leg cramps. There also exists an opinion that creative people with developed imagination are more likely to suffer from SP and experience more severe consequences rather than people with an analytical mindset who don’t believe in ghosts.

sleep fear
Sleep paralysis occurs in 5-40% of people aged 12-30, and most common among people with narcolepsy

It was found that sleep paralysis usually happens during the REM sleep phase when the activity of the brain is high while muscle activity is low. Sometimes a glitch may occur when a person seems to wake up and remain conscious, however, he experiences a muscle paralysis, retaining only the ability to breathe and observe the reality, often in a distorted manner. It is often caused by the desynchronization of the processes of switching on consciousness after sleep and muscle recovery. The "demon" in the room that comes at night is nothing but a phantasy of the half-asleep brain that, at that moment, is controlled by the limbic system, which is responsible for the formation of emotions, including fear.

How to stop sleep paralysis

Based on the surveys, most people experience sleep paralysis 1-2 times in life and it does not entail any serious consequences. However, in very rare cases, fear can be so strong that it can cause a heart attack. Nevertheless, patients who suffer from frequent manifestations of SP often tend to seek psychological and even medical help. This allows to identify health conditions and diseases that lead to the onset of the paralysis.

However, only a neurologist or somnologist can make a comprehensive diagnosis. If necessary, they will conduct polysomnography, psychological tests, MRI of the brain, etc. Further measures will depend on the condition of the person seeking help. Medicines and vitamins, or even physiotherapy procedures, can be prescribed. You can also adopt the following recommendations:

1. Keep a sleep diary. Doctors recommend recording all personal feelings before going to bed and after awakening and the duration of sleep, as well as a detailed description of the state when sleep paralysis occurs.

2. Follow a sleep schedule. It means going to bed and waking up at about the same time, and having about 7-8 hours of sleep each day.

3. Deal with your stress and anxiety. In the modern world, it is not easy to control stress. But we can learn how to distract ourselves from the disturbing life events at least during the night. Meditative practices and mindfulness exercises could help.

4. Avoid excessive mental stress before bedtime. Using gadgets or watching action movies and talk-shows activate and overexcite the brain, which makes it impossible to have a good relaxing sleep afterwards.

5. Take a relaxing bath and drink a soothing herbal tea. Take some time for yourself, give yourself a massage and ventilate the room. Do everything that will make your bedtime comfortable.

How to prevent sleep paralysis

  • Clearly realize that there is nothing supernatural about it, and it is just a temporary and accidental state. You need to mentally calm yourself down;
  • Do not resist the constraining force. Active attempts to free yourself from the state you are experiencing may lead to an even more exaggerated feeling of stiffness and helplessness;
  • Move those parts of the body that respond. For example, move your eyes, tongue, ears, and fingers. This can help you gain control of the body back;
  • “Launch” the brain by performing intellectual work such as telling a story, multiplying numbers or trying to remember the capitals of the neighboring countries.
good awakening girl
Regular sleep, a comfortable bedroom, proper nutrition, and avoiding watching TV before bedtime significantly reduce the risk of sleep paralysis

Considering that sleep paralysis most often occurs among people with certain sleep disorders or people with anxiety, one of the ways to address this problem is  eliminating sleep problems first. The Hypnopedia app offers a comprehensive solution to improve both sleep and mental health. A set of relaxing sounds in the applications will help to relax before going to bed. The music can also be played while sleeping and turns off after falling asleep (which is tracked by the Apple Watch) or automatically after 30 minutes. Sounds can be combined to create your favourite relaxing atmosphere, adjusted by the individual sound volume, and merged into playlists.

Ссылка App Store

Also in the application, you can select short motivational statements that will be played during sleep. Thanks to the sensors of the Apple Watch and the unique algorithm that collects and analyses the patterns of your sleep, the application defines the most favourable sleep stage and reproduces affirmations at the time best for perception. Your subconscious mind continues to process the information during sleep and is capable of perceiving small motivational statements. In the long term, they improve productivity, performance and other mental abilities. Moreover, the application helps you to wake up in the morning as easy as possible due to the smart alarm clock function. It selects the optimal awakening time for the body within the interval specified by the user (for example, from 6 to 6-30 am) and, with the help of gentle vibration of your wrist device, provides you with a fresh awakening without drowsiness, headache and the desire to drop your head back on the pillow.


Overall, sleep paralysis is, albeit frightening, but a rather rare and harmless sleep condition. However, it may also indicate the presence of serious illnesses. Even if it occurs as a one-time event, sleep paralysis is just another reason to take care of your sleep hygiene.

Hypnopedia Sleep Anxiety Dreams