The night visitor
UN/3/F+EOld Hag · the mara · incubus and succubus · kanashibari
Something heavy on the chest in the dark, under many names.
Waking unable to move, with a strong sense of a presence in the room and often a weight on the chest. Newfoundland calls it the Old Hag and Japan kanashibari, and Old English named the crushing spirit the mære, which survives in the word nightmare. Medieval demonology turned it into the incubus and succubus. The folklorist David Hufford showed in 1982 that the experience is real and recurring, and that people report it whether or not they know the tradition. It is now recognised as sleep paralysis, which explains why the figure is so consistent without explaining it away, and why abduction accounts that begin in bed so often share its features.
If you go looking
Sleep paralysis is common and harmless in itself, though frightening. Frequent episodes, especially with heavy daytime sleepiness, are worth mentioning to a GP.
Reading the code
Origin uncertain · embodiment 3 of 5, comes and goes · source: pre-modern folklore + recurring reports · key
Dates
The mære: Old English
Incubus and succubus: medieval demonology
Hufford's study: 1982
Related
Shadow people are the modern version of the same experience. Many abduction accounts that start in bed begin exactly here.