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Cited by 52Sleep and Wakefulness ResearchSleep and related disordersRestless Legs Syndrome Research

Disturbed dreaming and the instability of sleep: altered nonrapid eye movement sleep microstructure in individuals with frequent nightmares as revealed by the cyclic alternating pattern

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Simor, Péter, Bódizs, Róbert, Horváth, Klára, Ferri, Raffaele·2013·SLEEP
DOI 10.5665/sleep.2462PMC PMC3571751
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Abstract

STUDY OBJECTIVES: Nightmares are disturbing mental experiences during sleep that usually result in abrupt awakenings. Frequent nightmares are associated with poor subjective sleep quality, and recent polysomnographic data suggest that nightmare sufferers exhibit impaired sleep continuity during nonrapid eye movement (NREM) sleep. Because disrupted sleep might be related to abnormal arousal processes, the goal of this study was to examine polysomnographic arousal-related activities in a group of nightmare sufferers and a healthy control group. DESIGN: Sleep microstructure analysis was carried out by scoring the cyclic alternating pattern (CAP) in NREM sleep and the arousal index in rapid eye movement (REM) sleep on the second night of the polysomnographic examination. SETTING: Hospital-based sleep research laboratory. PARTICIPANTS: There were 17 in the nightmare (NMs) group and 23 in the healthy control (CTLs) group. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: The NMs group exhibited reduced amounts of CAP A1 subtype and increased CAP A2 and A3 subtypes, as well as longer duration of CAP A phases in comparison with CTLs. Moreover, these differences remained significant after controlling for the confounding factors of anxious and depressive symptoms. The absolute number and frequency of REM arousals did not differ significantly between the two groups. CONCLUSIONS: The results of our study indicate that NREM sleep microstructure is altered during nonsymptomatic nights of nightmares. Disrupted sleep in the NMs group seems to be related to abnormal arousal processes, specifically an imbalance in sleep-promoting and arousing mechanisms during sleep. CITATION: Simor P; Bódizs R; Horváth K; Ferri R. Disturbed dreaming and the instability of sleep: altered nonrapid eye movement sleep microstructure in individuals with frequent nightmares as revealed by the cyclic alternating pattern. SLEEP 2013;36(3):413-419.

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  • Theta activity and EEG characterized by high cortical activation appear crucial in the production and retrieval of DE.

    “Once again, the theta activity (Marquis et al., 2017) and the EEG characterized by high cortical activation (Simor et al., 2013; D'Atri et al., 2019) appear to be crucial in the production and retrieval of DE.”

    From The Functional Role of Dreaming in Emotional Processes (2019) · cites this paper as Simor et al., 2013

    The Discussion reports increased fast EEG activity and cortical activation in people with frequent nightmares, supporting the cortical-activation portion attributed to Simor et al. But it explicitly says the study cannot make direct inferences about arousals and nightmare formation because dream reports were not collected during the night; it does not establish a role in dream-experience production or retrieval. The sentence attributes theta activity to a different citation, not to Simor et al. (LLM, conf=0.87)

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  • Higher cortical desynchronization and fragmented sleep promote dreams in healthy subjects, nightmare sufferers, and narcoleptic patients.

    “It should be noted, the notion that higher cortical desynchronization and fragmented sleep promote dreams is not new in healthy subjects (Koulack and Goodenough, 1976; Scarpelli et al., 2017; Siclari et al., 2017) as well as in nightmare sufferers (Simor et al., 2013) and in narcoleptic patients (Dodet et al., 2015; D'Atri et al., 2019).”

    From The Functional Role of Dreaming in Emotional Processes (2019) · cites this paper as Simor et al., 2013

    The Discussion reports greater desynchronized cortical activity and impaired sleep continuity in frequent nightmare sufferers. But the Introduction says the altered sleep architecture was not linked to the occurrence of nightmares, and the Discussion calls for further investigation of the relationship between disrupted sleep and dreaming. The paper therefore supports an association with nightmare sufferers, not the claim that these changes promote dreams. (LLM, conf=0.87)

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  • Polysomnographic studies in patients with nightmares or nightmare disorders are characterized by alteration of sleep microstructure, including increased EEG alpha power, increased arousal-related phenomena in NREM-REM transitions, and imbalance in sleep-promoting and arousing mechanisms.

    “alteration of sleep microstructure characteristics (increase in EEG alpha power, increased arousal-related phenomena in NREM–REM transitions, imbalance in sleep-promoting and arousing mechanisms) [11–13].”

    From Nightmare Disorder and Isolated Sleep Paralysis (2021) · cites this paper as [11]

    The Abstract reports altered NREM sleep microstructure in frequent nightmare sufferers and describes a possible imbalance between sleep-promoting and arousing mechanisms. Our copy does not report increased EEG alpha power or increased arousal-related phenomena specifically at NREM–REM transitions; it reports no significant difference in REM arousals between groups. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

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Research works printed but not linked: 3

  1. [28]Sipos K, Sipos M, Spielberger C. A state-trait anxiety inventory (STAI) magyar változata. In: Mérei F, Szakács F, editors. Pszichodiagnosztikai Vademecum I/2. Budapest: Nemzeti Tankönyvkiadó; 1994. pp. 123–48. [Google Scholar]
  2. [30]Simor P, Köteles F, Bódizs R, Bárdos G. A szubjektív alvásminőség kérdőíves vizsgálata: a Groningen Alvásminőség Skála hazai validálása. Mentálhigiéné es Pszichoszomatika. 2009;10:249–61. [Google Scholar]
  3. [32]Rechtschaffen A, Kales A. Los Angeles: Brain Information Service. Brain Information Institute, UCLA; 1968. A manual of standardized terminology, technique and scoring system for sleep stages of human sleep. [Google Scholar]

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Authors
Simor, P., Bódizs, R., Horváth, K., & Ferri, R.
Affiliations
  • Budapest University of Technology and Economics (HU)
  • Semmelweis University (HU)
  • University of Oxford (GB)
  • 4Department of Neurology I.C. Sleep Research Centre, Oasi Institute for Research on Mental Retardation and Brain Aging (IRCCS), Troina, Italy
Corresponding author
Simor, Péter
ORCID
Venue
SLEEP
Publisher
Oxford University Press (OUP)
Published
2013-03-01
Volume
36
Issue
3
Pages
413-419
ISSN
  • 0161-8105 (ISSN-L)
  • 1550-9109
DOI
10.5665/sleep.2462
PMC
PMC3571751
OpenAlex
W1977187800
Cited by
52
References
51
Citations by year
2026: 4 · 2025: 2 · 2024: 6 · 2023: 3 · 2022: 3 · 2021: 3 · 2020: 3 · 2019: 9 · 2018: 1 · 2017: 4 · 2016: 3 · 2015: 6 · 2014: 2 · 2013: 3
FWCI
2.55
Type
journal article
Language
en
Open access
Locations
  • SLEEP (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Adelaide Research & Scholarship (AR&S) (University of Adelaide) (submittedVersion)
  • Dépôt institutionnel de l'Université libre de Bruxelles (Université Libre de Bruxelles) (submittedVersion)
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
  • Health Sciences › Medicine › Epidemiology › Restless Legs Syndrome Research
Keywords
nightmares, cyclic alternating pattern, sleep instability, sleep continuity
MeSH terms
Adult, Analysis of Variance, Dreams, Eye Movements, Female, Humans, Hungary, Male, Psychometrics, Sleep Wake Disorders, Polysomnography, Sleep Arousal Disorders, Young Adult

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