Sleep paralysis happens all the time
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Sleep paralysis happens all the time
By KARLA WARD
McClatchy Newspapers

FORT WORTH, Texas - Imagine waking up in the night and being unable to
move.
So you lie there for what seems like hours, trying to wiggle your
fingers or toes, but you are paralyzed.
You want to call out for help, but you can't draw a deep enough breath
to make a loud sound.
Eventually, you're able to move a little, and then your whole body
begins to respond again.
Scary, huh?
Weird, too.

But it happens to people all the time.
It's called sleep paralysis, and it typically occurs at the very
beginning or end of sleep. The experience lasts only a few minutes at
the most, and there's no harm done -- aside from the fright.
"It's terrifying the first time it happens," said Dr. Barbara Phillips,
director of the Samaritan Sleep Center and chairwoman of the board of
the National Sleep Foundation.
Phillips said in an e-mail interview that sleep paralysis happens as the
body is coming out of REM -- or rapid-eye-movement -- sleep.

"During non-REM sleep, our brains are 'turned off' but our bodies can be
active," she said. This is when people experience sleep disturbances
such as tooth-grinding or sleepwalking.
"In contrast, our brains are very active (probably as active as when we
are awake) during REM sleep, but we are actually paralyzed," she said.
Researchers think that's what keeps us from acting out our dreams.

"With sleep paralysis, the paralysis that is normal during REM sleep
intrudes into the waking state for one reason or another," she said.
Kathryn Hansen, director of the St. Joseph Hospital Sleep Wellness
Center, put it this way: "The brain wakes up before the body wakes up."

Sometimes, sleep paralysis is accompanied by hypnagogic hallucinations,
or "waking dreams," Phillips said.
In many such cases, people think they see a dark or menacing figure in
the room with them, or they hear a strange sound but can't pinpoint the
source. Some researchers have hypothesized that people who report alien
abductions are experiencing sleep paralysis in conjunction with such a
hallucination.

The experience of sleep paralysis combined with a hallucination "can be
very intense," said Dr. Kevin Nelson, a University of Kentucky
neurologist who has studied the correlation between sleep paralysis and
near-death experiences. "They may feel like there's a pressure on their
chest, that they can't breathe. They may feel like they're dying."

Nelson said episodes of sleep paralysis are "a very common thing," but
it's difficult to pinpoint exactly how common.
"The striking thing is, people don't talk about them," he said.
In some cultures, there are myths to explain the experience, or words
used to describe it. In those places, Nelson said, it is more frequently
reported.

The Japanese have a linguistic term, kanashibari, for the experience; in
Newfoundland, it is described as a visit from "the old hag."
"In some cultures it's very well recognized," he said.

Phillips said as many as 25 percent of people might be affected by sleep
paralysis at some point in their lives, and investigators at Stanford
University have suggested that as many as half of college students
experience it.
Nelson and other medical professionals who deal with sleep disorders
said they sometimes see patients who are disturbed by the paralysis but
have not talked to anyone about it because it seems so strange.

"They're not alone," Nelson said. "They're not weird because they have
it."
People are more likely to experience sleep paralysis, the experts said,
if they are undergoing sleep deprivation, work odd shifts or have
erratic sleep schedules. Hansen said it also can come with stress or
anxiety.

People who are in withdrawal from alcohol or drugs that can suppress REM
sleep, such as antidepressants, also can be predisposed to the
experience. For example, Phillips said, a person who misses a dose of
antidepressant medication might be at risk.
"It really just kind of correlates to lifestyles," she said.

The "classic example is the college kid who parties hard during spring
break, and wakes up on the beach unable to move," Phillips said. That
person has deprived himself or herself of sleep, gotten onto an odd
sleep schedule and drunk to much -- all three of the risk factors.
Sleep paralysis and hypnagogic hallucinations are generally harmless,
but the sleep experts said they can sometimes be associated with
narcolepsy.

In most cases, though, Hansen said they are a sign that the person needs
"to develop some good sleep habits," such as decreasing caffeine intake
before bedtime, getting regular exercise and going to bed and rising at
the same time each day.
"If sleep paralysis and extreme daytime sleepiness persist even with
adequate, appropriate sleep, it's time to see a doctor," Phillips said.

Hansen said that once, when she knew she hadn't gotten enough rest,
there was a moment when she couldn't move or speak as she was waking up
from a dream.

Sleep paralysis wasn't frightening to her, though.

"I laughed," she said. "Now I know how to describe it."