Understanding Sleep Paralysis: The Science Behind Nocturnal Immobility
Sleep paralysis is a temporary state in which you become conscious while your body is still in the muscle-paralyzed state that normally occurs during REM (rapid eye movement) sleep.
What actually happens?
During REM sleep, the brain naturally suppresses most skeletal-muscle activity. This process, called REM atonia, prevents you from physically acting out dreams.
Sometimes your awareness returns before that paralysis has switched off. You may be awake and able to see or hear your surroundings, but temporarily unable to move or speak.
Episodes usually last seconds to a few minutes and resolve on their own.
Why can it feel terrifying?
Sleep paralysis can involve vivid hallucinations. Some people feel a presence in the room, see a person or shadow, hear sounds, or experience a sensation of pressure on their chest. These experiences can feel completely real because elements of REM dreaming can overlap with waking consciousness.
Importantly, sleep paralysis itself isn’t evidence of a supernatural event.
What can make it more likely?
Episodes are associated with factors such as:
- Sleep deprivation or an irregular sleep schedule
- Stress
- Sleeping on your back
- Jet lag or disrupted sleep
- Narcolepsy and some other sleep disorders
What can you do?
Regular, adequate sleep and a consistent sleep schedule can reduce episodes for some people. During an episode, reminding yourself that the paralysis is temporary and will pass may help reduce panic. Focusing on slow breathing and attempting small movements, such as moving a finger or toe, can also be useful.
If episodes happen frequently, cause significant distress, or occur alongside extreme daytime sleepiness, sudden loss of muscle control, or other unusual sleep symptoms, talk with a healthcare professional or sleep specialist.
