I became interested in sleep and sleep disorders when my husband was diagnosed with sleep apnea. I didn't realize at the time that I also suffered from a sleep disorder. Oh, I knew that something strange happened to me some nights, but I put it down to stress and tried to ignore it.
The episodes, however, became more frequent and they began to worry me. I'd wake up in the night, unable to move. I'd have a sense of impending danger that I had to escape. I struggled and fought against the hold the paralysis had on me, and found that, if I could just wiggle one little finger, I'd be back to normal.
It took several months before I discovered I was suffering from sleep paralysis. This disorder is more common than it would appear. Many people fail to report it, afraid they'll be laughed at or that they may be going insane. Others, like I did, attribute it to other causes, including stress, and it is, in fact, often stress related.
The paralysis is not a disorder. It's a natural bodily function that causes us to be paralyzed during sleep. It prevents us hurting ourselves or others during dreams. It's when it follows us into the waking state that it becomes a disorder.
For some people, it may be mild, only a momentary paralysis as they awaken. For others, however, sleep paralysis can become a recurring and frightening experience. Because the paralysis follows them into the wakening world, so do their dreams, changing into vivid hallucinations that may be visual or auditory and may even involve the sense of smell. The victim feels a pressure on the chest, as though someone or something is sitting there. Sexual hallucinations are another possibility.
Over the years, sleep paralysis has been mistaken for things like UFO abduction and demon possession. One name for this disorder is The Old Hag. An excellent book on this topic, The Terror That Comes In the Night by David Hufford, explores the myths and folklore of sleep paralysis.
Hufford discusses such disparate topics as nightmares, sleep paralysis, hypnagogic hallucination and out of body experiences. But he also talks about the supernatural -- about ghosts, witches and UFOs. This is a fascinating book and makes one wonder what other tales from folklore, previously called myths, might actually be based on real events.
Causes of sleep paralysis are stress, depression and the onset of puberty. The hallucinations are a known side effect of another sleep disorder, narcolepsy. People suffering from this disorder often have vivid hallucinations during sleep onset or upon awakening, and brief episodes of total paralysis at the beginning or end of sleep.
One thing I haven't addressed here is out of body experience. Do OBEs really exist or are they just a state of the mind? I know I had some very strange experiences while in the throes of sleep paralysis. At that time we lived in a mobile home with a hallway along one side. Several times I felt I had left my body and was moving along that hallway up near the ceiling, sometimes drifting, at others whizzing along very quickly.