When you first hear a sleep paralysis story, it can be all to easy to dismiss as something fake or all in the teller’s mind. You wake up. You know you are in danger. An intruder is after you; the water is rising above your head; an evil creature is sitting on your chest and crushing the air out of your lungs. You need to escape, but you can’t move. You can’t even scream or call for help. Could it have been real?

The answer is yes: Sleep paralysis is real, and it happens for a very good reason. It would be extremely dangerous if we could act out our dreams in real life. Just ask comedian Mike Birbiglia. He has a rare sleep disorder in which he is not paralyzed while dreaming.

He made a very funny, very scary movie about his experience called Sleepwalk With Me. It tells the true story of the night he jumped through a second-floor motel window and ran bleeding across the lawn because he was dreaming about being chased.

Scary as it would be to wake up bleeding in our underwear on a motel lawn, it’s also pretty scary to wake up paralyzed in the middle of a nightmare. Sleep paralysis is common enough that most of us have experienced it at least once. Some people experience it frequently. An irregular sleep pattern and stress may be triggers.

Sleep paralysis may have been the inspiration for many of the scary images in art of demons sitting on the chests of helpless people. Some researchers believe sleep paralysis may even be the source of stories of alien abductions.

Photo Credit: IFC Films

A quick search of sleep paralysis stories turns up some truly scary ones. Here’s just a sampling of the terrors:

* A little creature is chewing something on the floor. In an instant it’s next to my head, and whispers “remember me?”
* An evil old lady over my head whispers, “darling…”
* Something is banging and scraping on the locked bedroom door, which starts to open.
* Something evil is pulling me into a deep and dangerous place. I can’t cry for help or move even a finger.
* I wake and a little girl in the corner of the bedroom is staring at me. Then she shrieks and runs to the bed and starts choking me.
* A giant beetle is getting ready to eat my body.

Sleep researchers believe we dream during the phase of sleep called REM (Rapid Eye Movement). It is believed that when we enter REM sleep, the brain cuts off the connection to the muscles, so we can run around in our dreams without risk of leaping out of bed. But when that paralysis lingers for a few minutes into wakefulness after a scary dream, it can be a very unpleasant experience.Those who experience sleep paralysis often report feeling like a devil is crouching on their chest, or that they feel as though they have been possessed by another entity. The real explanation is a bit less paranormal, but it’s certainly terrifying nonetheless. Knowing why your body has stopped being able to move won’t necessarily stop your panic when it occurs.

This story was first published on The Lineup

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