Sleep paralysis and folklore.

Sleep paralysis is a relatively new term to describe what for hundreds of years many believed to be a visitation by a malevolent creature which attacked its victims as they slept. The first clinical description of sleep paralysis was published in 1664 in a Dutch physician's case histories, where it was referred to as, 'Incubus or the Night-Mare [sic]'. In 1977, it was discovered more than 100 previously healthy people from various South East Asian communities had died mysteriously in their sleep. The individuals affected were dying at a rate of 92/100,000 from Sudden Unexplained Nocturnal Death Syndrome. No underlying cause was ever found, only that subsequent studies revealed a high rate of sleep paralysis and belief in the dab tsog (nightmare spirit) amongst members of the community. The nightmare/succubus is descended from Lilith. The earliest reference to Lilith is found in the Sumerian King list of 2400 BC known as Lilitu or she-demon, she bore children from her nocturnal unions with men. In other derivations, she was Adam's first wife who rather than 'obey' became a demon that preyed on women during childbirth. In modern Middle Eastern maternity wards, some women still wear amulets for protection. Today, clinical cause of these disturbances is sleep paralysis due to the unsuitable timing of REM sleep. During the 'Nightmare' episode, the sleeper becomes partially conscious during REM cycle, leaving the individual in a state between dream and wakefulness. For some, culture and the tradition of the nightmare is explanation enough.