Sleep Paralysis

Awareness during sleep paralysis (ASP)

• Inability to move in state between sleep and wakefulness

• Associated symptoms

  • Sense of presence

  • Auditory/visual/tactile hallucinations

  • Difficulty breathing

  • Intense fear

    • Amygdala overactivated

Sleep paralysis

• Associated with

  • Supine position

    ·       Sleeping on your back

  • Unfamiliar surroundings

  • Disrupted sleep patterns

  • Lasts between a few seconds and a few minutes

  • May be repeated several times in one night

  • False awakenings

• Not to be confused with

  • Bad dreams (nightmares)

  • Night terrors

    • you can move

    • Don’t remember it

Cross-cultural Incidence Rates

• Meta analysis 2011

  • General population: 7.6%

  • Psychiatric patients: 31.9%

  • Students: 28.3%

• Denis et al. (2015)

  • general UK sample (N = 852): 29.7%

• Importance of wording

  • Fukuda (1993) found rates of reporting amongst Japanese respondents varied with wording:

    • Kanashibari: 39.3%

    • “Condition”: 30.0%

    • Transient paralysis: 26.4%

Psychophysiology of sleep paralysis

• Sleep paralysis can be considered to be an intrusion of REM sleep characteristics into wakefulness:

  • muscles of the body are paralysed

  • associated hallucinations result from the brain activity typical of REM sleep

• Sleep-onset REM periods (SOREMPs) are associated with SP in both narcoleptics and non-narcoleptics

• §  More likely to have SP if you go straight from awake into REM

Cross-cultural interpretations of ASP

• Newfoundland – the “Old Hag”

• China – “ghost oppression”

• Japan – “kanashibari”

• St Lucia – “kokma”

• Europe in the Middle Ages – incubus and succubus

Witch trials

• Possible sleep paralysis episodes behind ‘evidence’ presented at many witch trials (Davies, 2003)

• Believed witches could send demons

  • Who had you wronged

Hmong Refugees and SUNDS

• SUNDS = Sudden unexplained nocturnal death syndrome (Adler, 1991, 1994)

  • From the late 1970s until the early 1990s, over one hundred Southeast Asians died mysteriously in their sleep, with a particularly high incidence amongst male Hmong refugees. (left Cambodia and gone to America)

• Minor abnormalities of the cardiac conduction system

  §  Deaths from SUNDS were only thought to have occurred amongst the refugees once they had reached the United States (typically within the first two years of arrival)

• SP episodes are interpreted by the Hmong as potentially lethal nocturnal spiritual attacks.

  • Predominance of male victims is explained by two factors:

    • Belief system explicitly holds that the male head of the household, who is also the spiritual leader of the family, would be the prime target for any attacking spirit.

    • Stress caused by the fact that males were no longer able to function effectively in their traditional patriarchal roles of head of the family and spiritual guide and protector.

  • Evidence showed that many of the victims of SUNDS had suffered in the past from sleep paralysis.

    • In home country the had traditional ways to treat this

      See Sharman and this reduced anxiety

SP and Alien Abduction Claims

• Confuse symptoms of sleep paralysis with signs of alien abduction

• Roper Poll (Hopkins et al., 1992)

  • Suggested 3.7 million Americans were abducted by aliens based on survey asking about symptoms during sleep

  • Hypnotic regression not a magical key to unlock “repressed” or hidden memories

    • If you go expecting memoires of alien abduction it a good chance that is what you will get

    • Provides a context in which narratives are generated based upon fantasy, imagination, prior knowledge and expectations

    • Narratives are then believed to be true memories

• Alien Abduction Claims

  • High association with sleep (French et al, 2002)

  • Abductees four times more likely to experience sleep paralysis (French et al, 2008)