Sleep paralysis (also called sleep atonia), is classified as an REM parasomnia and is defined as a form of paralysis that occurs when a person suddenly finds himself or herself unable to move for a few minutes, most often upon falling asleep or waking up. Sleep paralysis is sometimes accompanied by bizarre, surreal hallucinations; people report seeing ghosts, demons or supernatural beings. These episodes are generally brief, lasting just a few moments, but they can be intense and frightening.
What is Sleep Paralysis?
Have you ever woken up but felt briefly, terrifyingly unable to move or speak? You may have experienced sleep paralysis. During sleep paralysis (also called sleep atonia), a person wakes up, but motor activity is inhibited so they feel paralyzed.
Sleep paralysis is sometimes accompanied by bizarre, surreal hallucinations; people report seeing ghosts, demons or supernatural beings. These episodes are generally brief, lasting just a few moments, but they can be intense and frightening.
This condition is considered a REM parasomnia, or a disorder of arousal that arises from lighter-stage sleep. Like other parasomnias, sleep paralysis occurs during a transition between sleep and waking. Because people usually don’t move during sleep paralysis, it is not considered a dangerous sleep disorder. However, episodes are frightening, and in some cases, sleep paralysis can negatively impact a person’s quality of life.
Symptoms of Sleep Paralysis
Individuals experiencing sleep paralysis often report one or more of these sensations:
- Difficulty breathing, as if someone or something is crushing the chest
- Inability to move the eyes
- A feeling of dread or fear
- Seeing or sensing an evil presence in the room
How Common is Sleep Paralysis?
Around 7 percent of adults have experienced sleep paralysis; in adults with a psychiatric disorder, rates are as high as 35 percent. One study found that 7.6 percent of the general population, 28 percent of students, and nearly 32 percent of psychiatric patients reported at least one episode of sleep paralysis in their lifetimes.
Sleep paralysis becomes less common as people age; most people outgrow the condition by adulthood.
What Causes Sleep Paralysis?
During sleep, the body’s motor functions are suspended, which prevents people from acting out their dreams or engaging in potentially harmful actions. During sleep atonia, or sleep paralysis, the motor activity suspension continues even after the person wakes up.
The following conditions increase the risk of experiencing sleep paralysis:
- Increased levels of stress
- Irregular or insufficient sleep
- Use of hallucinogenic drugs, or withdrawal from these substances
- Sleeping while lying on the back
- Having a sleep disorder, especially narcolepsy, insomnia, shift work sleep disorder
- Having a mental health disorder, such as schizophrenia, anxiety, depression, or bipolar disorder (these individuals are twice as likely to have sleep hallucinations on at least a weekly basis)
Doctors generally don’t require tests to diagnose sleep paralysis. However, a physician will review your medical history, sleep patterns, and any underlying conditions or medications.
When sleep paralysis causes severe sleep disturbance, a physician may order the following tests:
- Polysomnogram, an overnight sleep study measuring heart, brain and lung activity
- Electromyogram, a test showing muscle activity
- Multiple Sleep Latency Test, an evaluation of naps. This test can help determine whether you have narcolepsy, which can contribute to sleep paralysis.
Sleep paralysis is usually benign, so most physicians do not recommend treatment. However, sleep paralysis can exacerbate pre-existing depression, anxiety, or sleep disorders, and may create fear of sleep or difficulty falling asleep. In those cases, doctors may recommend treatment to reduce or eliminate these episodes.
Lifestyle changes can offer relief for the mild to moderate sleep paralysis sufferers, such as:
- Improving sleep hygiene and minimizing sleep deprivation
- Avoiding drugs and alcohol
- Sleeping on the side instead of the back
- Getting regular exercise
- Avoiding stimulants like caffeine and large meals before bed
- Minimizing exposure to blue light before bed
In rare cases, medications such as antidepressants or the benzodiazepine Clonazepam are used to treat sleep paralysis.