Part 6?

The Scientific Explaination....kinda.
The medical establishment is quite aware of this phenomenon, but has a less sensational name than "old hag syndrome" for it. They call it "sleep paralysis" or SP (sometimes ISP for "isolated sleep paralysis").

So what causes it? Dr. Max Hirshkowitz, director of the Sleep Disorders Center at the Veterans Administration Medical Center in Houston, says that sleep paralysis occurs when the brain is in the transition state between deep, dreaming sleep (known as REM sleep for its rapid eye movement) and waking up. During REM dreaming sleep, the brain has turned off most of the body's muscle function so we cannot act out our dreams - we are temporarily paralyzed. Sheryl Crow Battles
The Old Hag

Rock singer Sheryl Crow is a victim of sleep paralysis, as she revealed in a 1996 interview with Rolling Stone magazine. "It's a bizarre and twisted feeling where you feel completely paralyzed. You are sure you are going to die."


"Sometimes your brain doesn't fully switch off those dreams - or the paralysis - when you wake up," Hirshkowitz told ABC News. "That would explain the 'frozen' feeling and hallucinations associated with sleep paralysis." According to his research, the effect only really lasts from a few seconds to as long as a minute, but in this half-dream half-awake state, to the victim it can seem much longer.

In her article, "Help! I Can't Move!," Florence Cardinal, About.com's Guide Sleep Disorders, writes: "Sleep paralysis is often accompanied by vivid hallucinations. There may be a sense someone is in the room, or even hovering over you. At other times, there seems to be pressure on the chest, as though someone or something perched there. There may even be sexual attacks associated with the hallucinations. The sound of footsteps, doors opening and closing, voices, all can be a very frightening part of sleep paralysis. These are known as Hypnagogic and Hypnopompic Experiences and they are what make people dread an episode of sleep paralysis."

For all their explanations, however, the sleep experts still do not know what causes the brain to screw up like this, or why some people experience it more than others.