Why can't I move when I wake up? Am I in danger?

Dear Reader,

No need to lose any sleep over this — your doctor is right that what you describe is normal and not dangerous. When you're snoozing and you move into REM (rapid eye movement) sleep, the deepest part of the sleep cycle, your body becomes largely disconnected from your brain — this is why we don't hurt ourselves or our bed-mates during active dreams. Sometimes, the mind disconnects too early or too late from the body, leaving you unable to move voluntarily. This temporary condition is called sleep paralysis, and it usually subsides after a minute or two.

Though sleep paralysis is harmless, it can be terrifying, especially if you don't know what's happening to you. Someone experiencing an episode may have hallucinations, or have the feeling that someone is in the room or sitting on his/her chest. Hearing and smell can also be involved, as can the feeling of floating or flying. Sleep paralysis is also common — so common that many different cultures have their own names and stories associated with the condition:

Newfoundland An "old hag" with supernatural powers was thought to sit on the sleeper's chest and cause paralysis.

West Indies
A "kokma" or ghost baby was thought to jump on the chest of the sleeper and attack his/her throat.

China
"Ggui ya" or pressure applied by a ghost was thought to be responsible for paralyzing the sleeper.

Some researchers believe that sleep paralysis could even be responsible for recent reports of late-night alien abductions.

The exact cause of sleep paralysis is unknown. The condition is often linked to the sleep disorder narcolepsy — a condition that causes people to lose control over when they fall asleep — but people who don't have narcolepsy experience episodes as well. Sleep paralysis seems to run in families and is more common in teenagers and people who have panic attacks.

A few things you can do to lessen the chances of encountering sleep paralysis include:

• Exercising at least twice a week
• Going to sleep and waking up at the same times each day
• Getting enough sleep to keep you feeling alert and awake throughout your day
• Reducing or better managing the amount of stress you deal with during the day (check out some Q&As in the Go Ask Alice! Stress and Anxiety archive for tips)

If you experience sleep paralysis more than once a week for at least six months, a health care provider or sleep specialist might be able to prescribe medication that can help you regulate your sleep patterns and manage the episodes.

In the meantime, perhaps knowing that this is within the range of normal will help you move toward sweeter dreams.