|
|
|
|
|
Henry Fuseli: Il sogno della regina Caterina, 1781-1783, Lytham St. Anne's (Lancashire), Town Hall
Psychological and Socio-Historical Aspects of RISP: An Analysis of the RISP Experiences of a Sample Population
There is no doubt that sleep paralysis (whether ISP or RISP) has been documented since as early as Hellenistic times, but with a wide variety of interpretations throughout time that reflect the culture, folklore and belief system of different populations or ethnic groups worldwide. The hypnogogic/hypnopompic hallucinations that are part of the secondary features of ISP/RISP have been interpreted as being [46]: indigestion ("hypocrites") for the Hellenic Greeks, guilt for the Romans and the Egyptians, witchcraft for the Mexicans, for the Yoruba people and for the Africans [47], demons for Medieval Europe, djinns for the Arabs, vampires for Europeans, hags (witches) for the Irish and Scottish (actually such hallucinations are still called "Old Hag" attacks in parts of the United States and of Canada, particularly in Newfoundland [48]), spectral foxes or spirit encounters for the Japanese, cats for the Chinese, ancestral ghosts for South-East Asians (e.g., [7], [13]), or the spirit of a dead unbaptised baby to different people in different parts of the world, etc...
In particular, the malevolent presence that is often perceived during ISP/RISP episodes, as well as the strong pressure on the chest (most often it is on the chest since sleep paralysis is also associated with lying in the supine position) were ascribed by the ancient Romans to incubus (incubare: to lie upon) and succubus attacks: incubi were believed to be male demons, and succubi female demons who were attacking the sleeper [46]. The Italian word "incubo" that is used nowadays to signify "nightmare" is derived from the Latin word "incubus." Similarly, the English word "nightmare", according to Webster's dictionary, is derived from the words "night" and "mare", where "mare" signifies "demon", and a "nightmare" was formerly believed to be an evil spirit that would haunt and suffocate sleeping people. There are other traditions of hags (as mentioned above) and other instantiations of evil or grotesque creatures (fairies, gremlins, and assorted "little people") attacking, or trying to possess or abduct their helpless victim [48b].
The phenomenon of sleep paralysis has also been vividly depicted in the arts and in literature: For example, Henry Fuseli's famous painting "The Nightmare" (1781) seems more likely inspired by the notion of sleep paralysis rather than any sleeping dream [49]; Henri de Maupassant's "Le Horla" (published in1887) contains a remarkably thorough and highly evocative account of sleep paralysis [50], [51] (it is interesting to note, with respect to the remark we made in section 4 concerning autoscopic hallucinations, that De Maupassant, as well as apparently having experienced terrifying sleep paralysis episodes, often saw a double of himself or "Doppelgänger" when fully awake, and he was ultimately committed to a mental institution); and sleep paralysis has also been described in F. Scott Fitzgerald's "The Beautiful and Damned" [52], as well as in Herman Melville's "Moby-Dick" a quarter of a century earlier than the first scientific description of the phenomenon by Silas Weir Mitchell in 1876 [52b], [52c]. Despite the various interpretations, the descriptions of the hallucinations are remarkably similar. In the modern, western industrialized world, especially in North America, most people have no connection with these ancient traditions (which also tried to explain these "demonic possessions" and developed rituals for exorcising the "possessions"), and so are quite mystified by the entire experience. Many of the descriptions of North Americans are rather vague and insubstantial in contradistinction to the more vivid and elaborate traditional descriptions. However, in North America, a new feature to explain the evil presence during sleep paralysis episodes is the phenomenon of so-called "alien abduction." A. Cheyne [53] presents an excellent sociological study of the similarity between the experience of sleep paralysis reported in the clinical and experimental literature and reports of alien abduction. Such similarity had already been theorized by popular writers of science such as the late Carl Sagan [54].
In relation with the above socio-historical summary of the phenomenon of sleep paralysis, we now briefly present preliminary results of a statistical analysis of the reports of ISP/RISP episodes posted by a sample population of 250 individuals on the sleep web site of the University of California in Los Angeles (UCLA). We point out that the sample is biased in the sense that the vast majority of respondents are of Anglo-Saxon origin. However, we think that most features of sleep paralysis have a sufficiently universal character that most statistical results are reasonably valid. The differences between this sample and a sample with a wide geographic distribution could really be significant in the interpretation of the sleep paralysis experience by the respondents, as the previous socio-historical summary seems to suggest.
First, the most common precipitating factors for ISP/RISP were found to be stress and/or disruption of sleep patterns, such as sleep interruption (in agreement with the clinical results presented in [33]), oversleeping, or napping. It has been reported in the scientific literature that other precipitating factors could be jet-lag [55], intense meditation [53] or intense intellectual concentration, sensitivity to heat or to cold, or even possible variations in geomagnetic activity (Conesa, 1995 [56]): periods of relatively quiet geomagnetic activity would be significantly associated with an increased incidence of episodes. It has also been suggested that the hypnogogic/hypnopompic hallucinations (and possibly also the experiences associated with the tertiary features) could occur more often in highly creative individuals, but this has not been confirmed statistically.
Secondly, no sex difference has been found in the prevalence of ISP/RISP and there seems to be three patterns of recurrence: most commonly, sleep paralysis occurs only once or infrequently in an individual's life, with interval of several months or even years. Occasionally, an ensemble of several frequent episodes occurs, but lasting only a short period of time (a few weeks). More rarely, episodes occur recurrently, frequently and over long periods of time spanning years, and "full-blown" episodes are predominant: such cases qualify as RISP.
Thirdly, the hypnogogic/hypnopompic hallucinations experienced during sleep paralysis episodes induce fear, usually intense, in over 90% of the individuals. In particular, the sensed evil presence, followed by the paralysis itself, is a terrorizing experience. The vast majority of the respondents who experience intense fear do not reach the second phase of a RISP episode. For those who do, the fear diminishes somewhat and puzzlement when seeing the physical surroundings (the room, the physical body from above) increases. The other 10% of respondents do not experience fear (or at least they have "learned" to control their fear or got used to the episodes if they happen frequently), although they generally do not enjoy the hallucinations, but they tend to find pleasure, excitement and enjoyment when experiencing the tertiary features.
Finally, about half of the respondents invoke a paranormal or a supernatural cause to explain their episodes (or at least, they have initially evoked such causes; upon learning about sleep paralysis, their belief tends to change to invoke natural, biological causes). Interestingly, none of the respondents has interpreted his/her episodes as alien abductions. Either individuals who report alien abductions have chosen not to post messages, or the association between sleep paralysis and alien abductions is not as strong as it is generally thought.
Go back to the index page