Sleep paralysis is a phenomenon that occurs either upon falling asleep or awakening and is thought to be a mix-up of normal REM sleep.
Washington State University psychologist Brian Sharpless recently published a book on sleep paralysis, in which he argues that the phenomenon may offer up a naturalistic explanation for some terrifying nighttime phenomena found in folklore all over the world — like stories of incubus or succubus attacks.
“Even though every culture puts its own stamp on it, the core experiences are similar,” Sharpless said. “It’s paralysis — except for the eyes — and conscious awareness during it.”
And for most people, it’s incredibly frightening.
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