Imagine you wake up in the middle of the night but you can’t move. Your eyes are wide open and you’re staring at the wall, but you can’t speak either. You’re fully aware that you’re awake, but you feel as if someone is holding you down.

This is called sleep paralysis.

Sleep paralysis is a feeling of being conscious but unable to move. It occurs when a person passes between stages of wakefulness and sleep. During these transitions, you may be unable to move or speak for just a few seconds or up to a few minutes.

According to the American Academy of Sleep Medicine, “some people also hallucinate during an episode. They may see, hear or feel things that are not there. They may even think that another person is in the room with them.” Because of this, these episodes may lead a person to feel anxious and afraid at that time.

Sleep paralysis is caused by your body’s sleep cycles. According to WEBMD,

“during sleep, your body alternates between REM (rapid eye movement) and NREM (non-rapid eye movement) sleep. Your muscles are ’turned off’ during REM sleep. If you become aware before the REM cycle has finished, you may notice that you cannot move or speak.”

The episode usually ends on its own, though  it may also end when someone touches you or speaks to you. Making an intense effort to move can also end an episode. Sleep paralysis may occur only once in your life, or it may also happen many times in a year. They usually start during teenage years or around the age of 20-30 years and can vary in their occurrences.  

If episodes continue to occur throughout a person’s life, the condition can lead to narcolepsy, a condition that WEBMD defines as  “…an overpowering need to sleep caused by a problem with the brain’s ability to regulate sleep.”

Although Sleep paralysis can be very frightening and cause a person to believe something is going on around them, it is not uncommon to be temporarily paralyzed during sleep and, according to doctors and experts in the sleep field, the condition does not appear to be a serious medical risk.