The incubus phenomenon: Prevalence, frequency and risk factors in psychiatric inpatients and university undergraduates.
Frontiers in Psychiatry January 1, 2022 Marc L Molendijk, Ouarda Bouachmir, Harriët Montagne et al.
The incubus phenomenon—a terrifying sleep-related experience of feeling a person or entity pressing on one's chest during sleep paralysis—was studied in 749 people (606 university students and 143 patients with schizophrenia spectrum disorders). Lifetime prevalence was 0.12 for students and 0.09 for patients, rates that did not differ statistically. These figures are substantially lower than the 0.41 reported in an earlier meta-analysis, which the authors suggest may reflect overgeneralization in prior studies. The phenomenon was more common among people with non-Western European backgrounds, possibly because it remains part of cultural and religious heritage in many non-Western countries. Among students, risk factors included psychotropic medication use and lifetime anxiety, eating, or sleeping disorders. No associations with age or gender were found.