The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform
Dan Denis - One of the best experts on this subject based on the ideXlab platform.
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Relationships between Sleep Paralysis and Sleep quality: current insights.
Nature and science of sleep, 2018Co-Authors: Dan DenisAbstract:Sleep Paralysis is the unusual experience of waking up in the night without the ability to move. Currently little is known about the experience, despite the fact that the vast majority of episodes are associated with extreme fear and in a minority of cases can lead to clinically significant levels of distress. The aim of this work was to review the existing literature pertaining to the relationship Sleep Paralysis has to Sleep more generally, measured both with subjective questionnaires and objective laboratory recordings. In terms of subjective Sleep variables, worse Sleep quality has been found in multiple studies to be associated with increased odds of Sleep Paralysis occurrence. In addition, insomnia symptoms (but not a diagnosed insomnia disorder) have also been found to predict Sleep Paralysis. Associations between Sleep Paralysis and other unusual and/or threatening Sleep experiences such as nightmares, exploding head syndrome, and lucid dreaming have been reported. In terms of objective measurements, the limited literature to date shows Sleep Paralysis to be a "mixed" state of consciousness, combining elements of rapid eye movement Sleep with elements of wakefulness. Future research needs to focus on longitudinal designs to disentangle the direction of effects and more typically employ a broader assessment of Sleep Paralysis that better captures associated features such as hallucinations, fear, and distress.
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Subjective Sleep-related variables in those who have and have not experienced Sleep Paralysis
Journal of sleep research, 2017Co-Authors: Dan Denis, Christopher C. French, Melanie N. Schneider, Alice M. GregoryAbstract:Research suggests that poor Sleep quality is related to the occurrence of Sleep Paralysis, although the precise relationship between these two variables is unknown. This association has generated interest due to the related possibility that improving Sleep quality could help to combat episodes of Sleep Paralysis. To date, studies examining the association between Sleep quality and Sleep Paralysis have typically measured Sleep quality using general measures such as the global score of the Pittsburgh Sleep quality index (PSQI). The aim of this study was to increase the precision of our understanding of the relationship between Sleep Paralysis and other aspects of Sleep by investigating associations between different Sleep-related variables and Sleep Paralysis. Using data from the G1219 twin/sibling study, analyses were performed on 862 individuals aged 22-32 (66% female). Results showed two components of the PSQI, Sleep latency and daytime dysfunction, were predictors of Sleep Paralysis. In addition, a number of other Sleep-related variables were significantly related to Sleep Paralysis. These were: insomnia symptoms, Sleep problems commonly related to traumatic experiences, pre-Sleep arousal, cognitions about Sleep, and excessive daytime Sleepiness. There was no relationship with Sleep-disordered breathing, diurnal preference, or Sleeping arrangements. Potential mechanisms underlying these results, and suggestions for future research are discussed.
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A systematic review of variables associated with Sleep Paralysis
Sleep medicine reviews, 2017Co-Authors: Dan Denis, Christopher C. French, Alice M. GregoryAbstract:Sleep Paralysis is a relatively common but under-researched phenomenon. While the causes are unknown, a number of studies have investigated potential risk factors. In this article, we conducted a systematic review on the available literature regarding variables associated with both the frequency and intensity of Sleep Paralysis episodes. A total of 42 studies met the inclusion criteria. For each study, sample size, study site, sex and age of participants, Sleep Paralysis measure, and results of analyses looking at the relationship(s) between Sleep Paralysis and associated variable(s) were extracted. A large number of variables were associated with Sleep Paralysis and a number of themes emerged. These were: substance use, stress and trauma, genetic influences, physical illness, personality, intelligence, anomalous beliefs, Sleep problems and disorders (both in terms of subjective Sleep quality and objective Sleep disruption), symptoms of psychiatric illness in non-clinical samples (particularly anxiety symptoms), and psychiatric disorders. Sleep Paralysis appears to be particularly prevalent in post-traumatic stress disorder, and to a less degree, panic disorder. Limitations of the current literature, directions for future research, and implications for clinical practice are discussed.
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Recurrent Isolated Sleep Paralysis
Reference Module in Neuroscience and Biobehavioral Psychology, 2017Co-Authors: Brian A. Sharpless, Dan DenisAbstract:Recurrent isolated Sleep Paralysis (RISP) is a Sleep-wake disorder characterized by the atonia of REM Sleep occurring in the context of a clear and wakeful sensorium. It is usually a frightening experience for sufferers, not only due to the Paralysis, but also because of accompanying hallucinations (i.e., waking dreams) which are vivid and often threatening. Although RISP is, at least in some ways, a well-understood condition, many practitioners are not aware of its clinical import and it is not often assessed in clinical or research settings. Assessment and treatment options are available, but the latter await better empirical support.
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Terror and bliss? Commonalities and distinctions between Sleep Paralysis, lucid dreaming, and their associations with waking life experiences
Journal of sleep research, 2016Co-Authors: Dan Denis, Giulia L. PoerioAbstract:Summary Sleep Paralysis and lucid dreaming are both dissociated experiences related to rapid eye movement (REM) Sleep. Anecdotal evidence suggests that episodes of Sleep Paralysis and lucid dreaming are related but different experiences. In this study we test this claim systematically for the first time in an online survey with 1928 participants (age range: 18–82 years; 53% female). Confirming anecdotal evidence, Sleep Paralysis and lucid dreaming frequency were related positively and this association was most apparent between lucid dreaming and Sleep Paralysis episodes featuring vestibular-motor hallucinations. Dissociative experiences were the only common (positive) predictor of both Sleep Paralysis and lucid dreaming. Both experiences showed different associations with other key variables of interest: Sleep Paralysis was predicted by Sleep quality, anxiety and life stress, whereas lucid dreaming was predicted by a positive constructive daydreaming style and vividness of sensory imagery. Overall, results suggest that dissociative experiences during wakefulness are reflected in dissociative experiences during REM Sleep; while Sleep Paralysis is related primarily to issues of Sleep quality and wellbeing, lucid dreaming may reflect a continuation of greater imaginative capacity and positive imagery in waking states.
Susan A. Clancy - One of the best experts on this subject based on the ideXlab platform.
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Sleep Paralysis and recovered memories of childhood sexual abuse: A reply to Pendergrast
Journal of Anxiety Disorders, 2006Co-Authors: Richard J. Mcnally, Susan A. ClancyAbstract:Abstract Pendergrast [Pendergrast, M. (in press). Sleep Paralysis and recovered memories of sexual abuse: comment on McNally and Clancy. Journal of Anxiety Disorders .] provides a critique of our study on Sleep Paralysis among adults reporting either repressed, recovered, or continuous memories of childhood sexual abuse [McNally, R. J., & Clancy, S. A. (2005a). Sleep Paralysis, sexual abuse, and space alien abduction. Transcultural Psychiatry , 42 , 113–122]. We address his concerns in this reply.
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Sleep Paralysis, sexual abuse, and space alien abduction.
Transcultural Psychiatry, 2005Co-Authors: Richard J. Mcnally, Susan A. ClancyAbstract:Sleep Paralysis accompanied by hypnopompic ('upon awakening') hallucinations is an often-frightening manifestation of discordance between the cognitive/perceptual and motor aspects of rapid eye movement (REM) Sleep. Awakening Sleepers become aware of an inability to move, and sometimes experience intrusion of dream mentation into waking consciousness (e.g. seeing intruders in the bedroom). In this article, we summarize two studies. In the first study, we assessed 10 individuals who reported abduction by space aliens and whose claims were linked to apparent episodes of Sleep Paralysis during which hypnopompic hallucinations were interpreted as alien beings. In the second study, adults reporting repressed, recovered, or continuous memories of childhood sexual abuse more often reported Sleep Paralysis than did a control group. Among the 31 reporting Sleep Paralysis, only one person linked it to abuse memories. This person was among the six recovered memory participants who reported Sleep Paralysis (i.e. 17% rate of interpreting it as abuse-related). People rely on personally plausible cultural narratives to interpret these otherwise baffling Sleep Paralysis episodes.
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Sleep Paralysis in adults reporting repressed, recovered, or continuous memories of childhood sexual abuse.
Journal of anxiety disorders, 2005Co-Authors: Richard J. Mcnally, Susan A. ClancyAbstract:Abstract Sleep Paralysis typically occurs as individuals awaken from rapid eye movement Sleep before motor Paralysis wanes. Many episodes are accompanied by tactile and visual hallucinations, often of threatening intruders in the bedroom. Pendergrast [Victims of Memory: Incest Accusations and Shattered Lives, HarperCollins, London, 1996] proposed that individuals who report repressed or recovered memories of childhood sexual abuse (CSA) may misinterpret episodes of Sleep Paralysis as reemerging fragments of dissociated (“repressed”) memories of CSA. To investigate this issue, we administered a Sleep Paralysis questionnaire to people reporting either repressed (n = 18), recovered (n = 14), or continuous (n = 36) memories of CSA, or to a control group reporting no history of CSA (n = 16). The prevalence of Sleep Paralysis was: repressed memory group (44%), recovered memory group (43%), continuous memory group (47%), and control group (13%). Among the six individuals in the recovered memory group who had experienced Sleep Paralysis, one interpreted it as related to sexual abuse (i.e., a rate of 17%). All other participants who had reported Sleep Paralysis embraced other interpretations (e.g., saw a ghost). Dissociation and depressive symptoms were more common among those who had experienced Sleep Paralysis than among those who denied having experienced it.
Alice M. Gregory - One of the best experts on this subject based on the ideXlab platform.
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Subjective Sleep-related variables in those who have and have not experienced Sleep Paralysis
Journal of sleep research, 2017Co-Authors: Dan Denis, Christopher C. French, Melanie N. Schneider, Alice M. GregoryAbstract:Research suggests that poor Sleep quality is related to the occurrence of Sleep Paralysis, although the precise relationship between these two variables is unknown. This association has generated interest due to the related possibility that improving Sleep quality could help to combat episodes of Sleep Paralysis. To date, studies examining the association between Sleep quality and Sleep Paralysis have typically measured Sleep quality using general measures such as the global score of the Pittsburgh Sleep quality index (PSQI). The aim of this study was to increase the precision of our understanding of the relationship between Sleep Paralysis and other aspects of Sleep by investigating associations between different Sleep-related variables and Sleep Paralysis. Using data from the G1219 twin/sibling study, analyses were performed on 862 individuals aged 22-32 (66% female). Results showed two components of the PSQI, Sleep latency and daytime dysfunction, were predictors of Sleep Paralysis. In addition, a number of other Sleep-related variables were significantly related to Sleep Paralysis. These were: insomnia symptoms, Sleep problems commonly related to traumatic experiences, pre-Sleep arousal, cognitions about Sleep, and excessive daytime Sleepiness. There was no relationship with Sleep-disordered breathing, diurnal preference, or Sleeping arrangements. Potential mechanisms underlying these results, and suggestions for future research are discussed.
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A systematic review of variables associated with Sleep Paralysis
Sleep medicine reviews, 2017Co-Authors: Dan Denis, Christopher C. French, Alice M. GregoryAbstract:Sleep Paralysis is a relatively common but under-researched phenomenon. While the causes are unknown, a number of studies have investigated potential risk factors. In this article, we conducted a systematic review on the available literature regarding variables associated with both the frequency and intensity of Sleep Paralysis episodes. A total of 42 studies met the inclusion criteria. For each study, sample size, study site, sex and age of participants, Sleep Paralysis measure, and results of analyses looking at the relationship(s) between Sleep Paralysis and associated variable(s) were extracted. A large number of variables were associated with Sleep Paralysis and a number of themes emerged. These were: substance use, stress and trauma, genetic influences, physical illness, personality, intelligence, anomalous beliefs, Sleep problems and disorders (both in terms of subjective Sleep quality and objective Sleep disruption), symptoms of psychiatric illness in non-clinical samples (particularly anxiety symptoms), and psychiatric disorders. Sleep Paralysis appears to be particularly prevalent in post-traumatic stress disorder, and to a less degree, panic disorder. Limitations of the current literature, directions for future research, and implications for clinical practice are discussed.
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a twin and molecular genetics study of Sleep Paralysis and associated factors
Journal of Sleep Research, 2015Co-Authors: Dan Denis, Christopher C. French, Richard Rowe, Helena M S Zavos, Patrick M Nolan, Michael J Parsons, Alice M. GregoryAbstract:Sleep Paralysis is a relatively common but under-researched phenomenon. In this paper we examine prevalence in a UK sample and associations with candidate risk factors. This is the first study to investigate the heritability of Sleep Paralysis in a twin sample and to explore genetic associations between Sleep Paralysis and a number of circadian expressed single nucleotide polymorphisms. Analyses are based on data from the Genesis1219 twin/sibling study, a community sample of twins/siblings from England and Wales. In total, data from 862 participants aged 22-32 years (34% male) were used in the study. This sample consisted of monozygotic and dizygotic twins and siblings. It was found that self-reports of general Sleep quality, anxiety symptoms and exposure to threatening events were all associated independently with Sleep Paralysis. There was moderate genetic influence on Sleep Paralysis (53%). Polymorphisms in the PER2 gene were associated with Sleep Paralysis in additive and dominant models of inheritance-although significance was not reached once a Bonferroni correction was applied. It is concluded that factors associated with disrupted Sleep cycles appear to be associated with Sleep Paralysis. In this sample of young adults, Sleep Paralysis was moderately heritable. Future work should examine specific polymorphisms associated with differences in circadian rhythms and Sleep homeostasis further in association with Sleep Paralysis.
Richard J. Mcnally - One of the best experts on this subject based on the ideXlab platform.
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Sleep Paralysis and recovered memories of childhood sexual abuse: A reply to Pendergrast
Journal of Anxiety Disorders, 2006Co-Authors: Richard J. Mcnally, Susan A. ClancyAbstract:Abstract Pendergrast [Pendergrast, M. (in press). Sleep Paralysis and recovered memories of sexual abuse: comment on McNally and Clancy. Journal of Anxiety Disorders .] provides a critique of our study on Sleep Paralysis among adults reporting either repressed, recovered, or continuous memories of childhood sexual abuse [McNally, R. J., & Clancy, S. A. (2005a). Sleep Paralysis, sexual abuse, and space alien abduction. Transcultural Psychiatry , 42 , 113–122]. We address his concerns in this reply.
-
Sleep Paralysis, sexual abuse, and space alien abduction.
Transcultural Psychiatry, 2005Co-Authors: Richard J. Mcnally, Susan A. ClancyAbstract:Sleep Paralysis accompanied by hypnopompic ('upon awakening') hallucinations is an often-frightening manifestation of discordance between the cognitive/perceptual and motor aspects of rapid eye movement (REM) Sleep. Awakening Sleepers become aware of an inability to move, and sometimes experience intrusion of dream mentation into waking consciousness (e.g. seeing intruders in the bedroom). In this article, we summarize two studies. In the first study, we assessed 10 individuals who reported abduction by space aliens and whose claims were linked to apparent episodes of Sleep Paralysis during which hypnopompic hallucinations were interpreted as alien beings. In the second study, adults reporting repressed, recovered, or continuous memories of childhood sexual abuse more often reported Sleep Paralysis than did a control group. Among the 31 reporting Sleep Paralysis, only one person linked it to abuse memories. This person was among the six recovered memory participants who reported Sleep Paralysis (i.e. 17% rate of interpreting it as abuse-related). People rely on personally plausible cultural narratives to interpret these otherwise baffling Sleep Paralysis episodes.
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Sleep Paralysis in adults reporting repressed, recovered, or continuous memories of childhood sexual abuse.
Journal of anxiety disorders, 2005Co-Authors: Richard J. Mcnally, Susan A. ClancyAbstract:Abstract Sleep Paralysis typically occurs as individuals awaken from rapid eye movement Sleep before motor Paralysis wanes. Many episodes are accompanied by tactile and visual hallucinations, often of threatening intruders in the bedroom. Pendergrast [Victims of Memory: Incest Accusations and Shattered Lives, HarperCollins, London, 1996] proposed that individuals who report repressed or recovered memories of childhood sexual abuse (CSA) may misinterpret episodes of Sleep Paralysis as reemerging fragments of dissociated (“repressed”) memories of CSA. To investigate this issue, we administered a Sleep Paralysis questionnaire to people reporting either repressed (n = 18), recovered (n = 14), or continuous (n = 36) memories of CSA, or to a control group reporting no history of CSA (n = 16). The prevalence of Sleep Paralysis was: repressed memory group (44%), recovered memory group (43%), continuous memory group (47%), and control group (13%). Among the six individuals in the recovered memory group who had experienced Sleep Paralysis, one interpreted it as related to sexual abuse (i.e., a rate of 17%). All other participants who had reported Sleep Paralysis embraced other interpretations (e.g., saw a ghost). Dissociation and depressive symptoms were more common among those who had experienced Sleep Paralysis than among those who denied having experienced it.
Baland Jalal - One of the best experts on this subject based on the ideXlab platform.
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Sleep Paralysis in Italy: Frequency, hallucinatory experiences, and other features.
Transcultural psychiatry, 2020Co-Authors: Baland Jalal, Andrea Romanelli, Devon E. HintonAbstract:Previous research has found supernatural beliefs about Sleep Paralysis (SP) to be very prevalent in Italy, with over one third of SP sufferers believing that their SP might have been caused by a su...
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Beliefs about Sleep Paralysis in Turkey: Karabasan attack.
Transcultural psychiatry, 2020Co-Authors: Baland Jalal, H. Sevde Eskici, Ceren Acarturk, Devon E. HintonAbstract:The present study examined explanations of Sleep Paralysis (SP) in Turkey. The participants were 59 college students recruited in Istanbul, Turkey, who had experienced SP at least once in their lif...
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The neuropharmacology of Sleep Paralysis hallucinations: serotonin 2A activation and a novel therapeutic drug
Psychopharmacology, 2018Co-Authors: Baland JalalAbstract:Sleep Paralysis is a state of involuntary immobility occurring at Sleep onset or offset, often accompanied by uncanny “ghost-like” hallucinations and extreme fear reactions. I provide here a neuropharmacological account for these hallucinatory experiences by evoking the role of the serotonin 2A receptor (5-HT_2AR). Research has shown that 5-HT_2AR activation can induce visual hallucinations, “mystical” subjective states, and out-of-body experiences (OBEs), and modulate fear circuits. Hallucinatory experiences triggered by serotonin—serotonergic (“pseudo”) hallucinations, induced by hallucinogenic drugs—tend to be “dream-like” with the experiencer having insight (“meta-awareness”) that he is hallucinating, unlike dopaminergic (“psychotic” and “life-like”) hallucinations where such insight is lost. Indeed, hallucinatory experiences during Sleep Paralysis have the classic features of serotonergic hallucinations, and are strikingly similar to perceptual and subjective states induced by hallucinogenic drugs (e.g., lysergic acid diethylamide [LSD] and psilocybin), i.e., they entail visual hallucinations, mystical experiences, OBEs, and extreme fear reactions. I propose a possible mechanism whereby serotonin could be functionally implicated in generating Sleep Paralysis hallucinations and fear reactions through 5-HT_2AR activity. Moreover, I speculate on the role of 5-HT_2C receptors vis-à-vis anxiety and panic during Sleep Paralysis, and the orbitofrontal cortex—rich with 5-HT_2A receptors—in influencing visual pathways during Sleep Paralysis, and, in effect, hallucinations. Finally, I propose, for the first time, a drug to target Sleep Paralysis hallucinations and fear reactions, namely the selective 5-HT_2AR inverse agonist, pimavanserin. This account implicates gene HTR2A on chromosome 13q as the underlying cause of Sleep Paralysis hallucinations and could be explored using positron emission tomography.
