The DOI matches its Crossref record; 17 of the 17 references it cites were found in a registry or an index.
In short photoperiods, human sleep is biphasic
Abstract
SUMMARY Results of a photoperiod experiment show that human sleep can be unconsolidated and polyphasic, like the sleep of other animals. When normal individuals were transferred from a conventional 16‐h photoperiod to an experimental 10‐h photo‐period, their sleep episodes expanded and usually divided into two symmetrical bouts, several hours in duration, with a 1–3 h waking interval between them. The durations of nocturnal melatonin secretion and of the nocturnal phase of rising sleepiness (measured in a constant routine protocol) also expanded, indicating that the timing of internal processes that control sleep and melatonin, such as circadian rhythms, had been modified by the change in photoperiod. Previous work suggests that the experimental results could be simulated with dual‐oscillators, entrained separately to dawn and dusk, or with a two‐process model, having a lowered threshold for sleep‐onset during the scotoperiod.
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“Under certain circumstances, the oscillations of E and M can become dissociated from one another. In this situation, coupling forces between the two components continue to operate and tend to draw the components into either of two metastable modes of coupling that are 180° apart17,19.”
From Bipolar mood cycles associated with lunar entrainment of a circadian rhythm (2018) · cites this paper as [19]
Citations
Cites
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Self-citation
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Schulz, H., & Dirlich, G. (2023) · Journal of Sleep Research · doi:10.1111/jsr.14067
“This corresponds with the finding that sleep distribution in human subjects becomes bimodal if the photoperiod is short (Wehr, 1992).”
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“The constant 𝑎 𝑐 in (3) is the scale factor of the circadian process on sleep drive, which was first proposed and assigned numerical values in [15] to fit the experimental data of the photoperiod experiment reported in [16].”
Metadata
- Authors
- WEHR, T. A.
- Affiliations
- National Institutes of Health (US)
- Corresponding author
- WEHR, THOMAS A.
- ORCID
- WEHR, THOMAS A.
- Venue
- Journal of Sleep Research
- Publisher
- Wiley
- Published
- 1992-06
- Volume
- 1
- Issue
- 2
- Pages
- 103-107
- ISSN
- 0962-1105 (ISSN-L)
- 1365-2869
- OpenAlex
- W1968064632
- Cited by
- 115
- References
- 17
- Citations by year
- 2026: 5 · 2025: 6 · 2024: 6 · 2023: 5 · 2022: 6 · 2021: 7 · 2020: 7 · 2019: 5 · 2018: 10 · 2017: 4 · 2016: 6 · 2015: 8 · 2014: 7 · 2013: 7 · 2012: 1
- FWCI
- 1.31
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of Sleep Research (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
- Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
- Keywords
- polyphasic sleep, short-day photoperiod, sleep consolidation, circadian rhythm, melatonin secretion, sleepiness, constant routine, two-process model
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