See ghosts in your sleep? Or jerk awake and can't move? Here's why it happens

by Meghan Holohan /  / Updated  / Source: TODAY

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You jerk awake in the middle of the night in confusion. Is there a figure standing in the corner of the room? Your brain begs your limbs to move, but nothing happens. The anxiety increases. Your eyes scan the room. Just as you’re about to hit peak panic, you sit up and the figure disappears.

You’ve just experienced sleep paralysis, one of many “parasomnias,” which is the name experts give to all sorts of weird things that occur during sleep.

Sleep paralysis happens when the brain incapacitates the body to prevent it from acting out the vivid dreams occurring during REM (or, rapid eye movement) sleep. It often comes with a feeling of immobility, and a sense of choking.

The good news? It’s absolutely normal. Even if it’s terrifying.

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But when sleep paralysis happens outside of deep sleep — when a person is just dozing off or waking up — it can be “disruptive of the architecture of sleep,” said Baland Jalal, a researcher who investigates the phenomenon. That could lead to more sleep paralysis. People with poor sleeping habits experience the phenomenon more frequently.

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While the mechanisms behind sleep paralysis remain murky, Jalal said stress and worry play a part. Recent research indicates that people with anxiety and PTSD report experiencing sleep paralysis more frequently.

“People who are anxious have much more emotional sleep. [They] are more likely to wake up during REM,” said Jalal. “If you have sleep paralysis, you probably also have anxiety.”

The anxiety feeds into the sleep paralysis, said Jalal. People fret about experiencing the panicky feelings of sleep paralysis, which makes it more likely to occur again.

While about 6 percent of the population will experience sleep paralysis at one point in their lives, it occurs in about 30 to 50 percent of people with narcolepsy, a sleep disorder that includes excessive daytime sleepiness, cataplexy, sleep paralysis, and hallucinations, said Dr. Nathaniel Watson, president of the American Academy of Sleep Medicine and co-director of the University of Washington Medical Sleep Center.

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Students are more likely to experience sleep paralysis with as many as 28.3 percent of students reporting it.

For most people, “it is not indicative of any kind of disease,” said Watson. While the experience feels frightening, the episodes last only a few seconds or minutes at most.

“These are called state transitions and sometimes they are not a clean break from one to the other,” Watson said.

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Most people slip out of it as quickly as they fell into it. A light touch from a partner can be enough to stop it, he said.

While not everyone who has sleep paralysis experiences hallucinations, seeing a person or a ghost in the room is the most common vision, said Jalal.

Hallucinations vary by culture — the Chinese call it “gui ya” or ghost pressure because they believe a ghost sits on people’s chests. In Newfoundland, it is the “old hag” because people see a witch and in Egypt people see Jinn (what Westerns call genies), which are known to hunt and sometimes kills their victims.

As for the United States? Some experts have suggested that alien abductions are really just intense bouts of sleep paralysis.

“When you live in a culture where you are afraid of it, you are much more likely to be anxious [about sleep paralysis] and experience it,” Jalal said.

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