The DOI matches its Crossref record; 8 of the 8 references it cites were found in a registry or an index.
Intrinsic near-24-h pacemaker period determines limits of circadian entrainment to a weak synchronizer in humans
Open accessAbstract
Endogenous circadian clocks are robust regulators of physiology and behavior. Synchronization or entrainment of biological clocks to environmental time is adaptive and important for physiological homeostasis and for the proper timing of species-specific behaviors. We studied subjects in the laboratory for up to 55 days each to determine the ability to entrain the human clock to a weak circadian synchronizing stimulus [scheduled activity–rest cycle in very dim (≈1.5 lux in the angle of gaze) light–dark cycle] at three ≈24-h periods: 23.5, 24.0, and 24.6 h. These studies allowed us to test two competing hypotheses as to whether the period of the human circadian pacemaker is near to or much longer than 24 h. We report here that imposition of a sleep–wake schedule with exposure to the equivalent of candlelight during wakefulness and darkness during sleep is usually sufficient to maintain circadian entrainment to the 24-h day but not to a 23.5- or 24.6-h day. Our results demonstrate functionally that, in normally entrained sighted adults, the average intrinsic circadian period of the human biological clock is very close to 24 h. Either exposure to very dim light and/or the scheduled sleep–wake cycle itself can entrain this near-24-h intrinsic period of the human circadian pacemaker to the 24-h day.
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Cites
Stability, precision, and near-24-hour period of the human circadian pacemaker
Czeisler, C. A., Duffy, J. F., Shanahan, T. L., Brown, E. N., Mitchell, J. F., Rimmer, D. W., Ronda, J. M., Silva, E. J., Allan, J. S., Emens, J. S., et al. (1999) · Science · doi:10.1126/science.284.5423.2177 · Cited by 1,705
An h Per2 Phosphorylation Site Mutation in Familial Advanced Sleep Phase Syndrome
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Interacting molecular loops in the mammalian circadian clock
Shearman, L. P., Sriram, S., Weaver, D. R., Maywood, E. S., Chaves, I., Zheng, B., Kume, K., Lee, C. C., van der, G. T. J., Horst, et al. (2000) · Science · doi:10.1126/science.288.5468.1013 · Cited by 1,367
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Self-citationCircadian oscillation of a mammalian homologue of the Drosophila period gene
Tei, H., Okamura, H., Shigeyoshi, Y., Fukuhara, C., Ozawa, R., Hirose, M., & Sakaki, Y. (1997) · Nature · doi:10.1038/39086 · Cited by 792
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Self-citationDose-response relationships for resetting of human circadian clock by light
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Self-citationEntrainment of free-running circadian rhythms by melatonin in blind people
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Cited by
Sleep Patterns and Predictors of Disturbed Sleep in a Large Population of College Students
Lund, H. G., Reider, B. D., Whiting, A. B., & Prichard, J. R. (2010) · Journal of Adolescent Health · doi:10.1016/j.jadohealth.2009.06.016 · Cited by 1,907
Sleep, circadian rhythms, and delayed phase in adolescence
Crowley, S. J., Acebo, C., & Carskadon, M. A. (2007) · Sleep Medicine · doi:10.1016/j.sleep.2006.12.002 · Cited by 1,127
Entrainment of the Human Circadian Clock to the Natural Light-Dark Cycle
Wright, K. P., McHill, A. W., Birks, B. R., Griffin, B. R., Rusterholz, T., & Chinoy, E. D. (2013) · Current Biology · doi:10.1016/j.cub.2013.06.039 · Cited by 783
Self-citationImpact of insufficient sleep on total daily energy expenditure, food intake, and weight gain
Markwald, R. R., Melanson, E. L., Smith, M. R., Higgins, J., Perreault, L., Eckel, R. H., & Wright, K. P. (2013) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1216951110 · Cited by 810
Self-citationRegulation of adolescent sleep: Implications for behavior
CARSKADON, M. A., ACEBO, C., & JENNI, O. G. (2004) · Annals of the New York Academy of Sciences · doi:10.1196/annals.1308.032 · Cited by 792
Metadata
- Authors
- Wright, K. P., Hughes, R. J., Kronauer, R. E., Dijk, D.-J., & Czeisler, C. A.
- Venue
- Proceedings of the National Academy of Sciences
- Published
- 2001-11-20
- Volume
- 98
- Issue
- 24
- Pages
- 14027-14032
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- OpenAlex
- W2023173564
- Cited by
- 255
- References
- 8
- FWCI
- 2.61
- Type
- journal article
- Language
- en
- Open access
- green
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- Wright, K. P., Hughes, R. J., Kronauer, R. E., Dijk, D.-J., & Czeisler, C. A. (2001). Intrinsic near-24-h pacemaker period determines limits of circadian entrainment to a weak synchronizer in humans. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.201530198
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