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Cited by 63Sleep and Work-Related FatigueSleep and Wakefulness ResearchCircadian rhythm and melatonin

Modeling Napping, Post-Lunch Dip, and Other Variations in Human Sleep Propensity

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Bes, Frederik, Jobert, Marc, Schulz, Hartmu·2009·Sleep
DOI 10.1093/sleep/32.3.392PMC PMC2647793
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Abstract

STUDY OBJECTIVES: To model sleep propensity (SP) as a continuous variable across 24 hours and to model the post-noon nap zone, or post-lunch dip in performance, and the early evening trough in SP. METHODS: The present model is a variant of the 2-process model with 2 major modifications. (1) The circadian threshold process was replaced by sleep drive R, derived from REM sleep propensity, which shows a strong circadian modulation. (2) The model is based on a multiplicative interaction between the 2 input variables S and R. The model parameters S and R were estimated from experimental data. Thus, SP is modeled by multiplicative interaction of 2 sleep drives, S and R, the former of homeostatic, the latter of circadian nature. In short: SP = S x R. RESULTS: Under the condition of normal phase and duration of nighttime sleep, SP across 24 hours displays 4 characteristics, (a) a major peak at nighttime, (b) a secondary increase, which peaks post-noon, (c) a first local minimum at sleep offset in the morning, and (d) a second local minimum in the early evening hours. Model simulations with either delayed or advanced sleep times suggest that the magnitude of the post-noon nap zone depends on the phase of the major sleep period within 24 hours. While the nap zone is attenuated or disappears when night sleep is delayed, SP increases during daytime when night sleep is advanced. In all conditions, the evening local minimum of SP remained stable. CONCLUSIONS: SP can be modeled as a continuous variable, based on the multiplicative interaction of 2 basic sleep drives. The model predictions are in agreement with known variations of SP across 24 hours.

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  • Mexican-Americans who were not acculturated to American norms were less likely to demonstrate basic knowledge about sleep disorders and their symptoms.

    “Sell and colleagues found that Mexican-Americans who were not acculturated to American norms were less likely to be able to demonstrate basic knowledge about sleep disorders and what the symptoms of sleep disorders look like (Sell et al., 2009).”

    From Addressing sleep disturbances: an opportunity to prevent cardiometabolic disease? (2014) · cites this paper as Sell et al., 2009

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Authors
Bes, F., Jobert, M., & Schulz, H.
Affiliations
Freie Universität Berlin (DE)
ORCID
Jobert, Marc
Venue
Sleep
Publisher
Oxford University Press (OUP)
Published
2009-03
Volume
32
Issue
3
Pages
392-398
ISSN
  • 0161-8105 (ISSN-L)
  • 1550-9109
DOI
10.1093/sleep/32.3.392
PMC
PMC2647793
OpenAlex
W64524053
Cited by
63
References
44
Citations by year
2026: 3 · 2025: 5 · 2024: 4 · 2023: 3 · 2022: 5 · 2021: 9 · 2020: 4 · 2019: 2 · 2018: 1 · 2017: 2 · 2016: 3 · 2015: 3 · 2014: 3 · 2013: 6 · 2012: 3
FWCI
4.22
Type
journal article
Language
en
Open access
Locations
  • SLEEP (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
Keywords
sleep propensity, sleep drive, circadian rhythm, homeostatic sleep drive, sleep timing, circadian phase
MeSH terms
Body Temperature Regulation, Circadian Rhythm, Computer Graphics, Drive, Homeostasis, Humans, Models, Theoretical, Probability, Reaction Time, Sleep, REM, Wakefulness, Sleep Phase Chronotherapy

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