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Cited by 580Sleep and Work-Related FatigueCircadian rhythm and melatoninSleep and Wakefulness Research

Exposure to Bright Light and Darkness to Treat Physiologic Maladaptation to Night Work

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Czeisler, Charles A., Johnson, Michael P., Duffy, Jeanne F., Brown, Emery N., Ronda, Joseph M., Kronauer, Richard E.·1990·New England Journal of Medicine
DOI 10.1056/nejm199005033221801
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Abstract

Working at night results in a misalignment between the sleep-wake cycle and the output of the hypothalamic pacemaker that regulates the circadian rhythms of certain physiologic and behavioral variables. We evaluated whether such physiologic maladaptation to nighttime work could be prevented effectively by a treatment regimen of exposure to bright light during the night and darkness during the day. We assessed the functioning of the circadian pacemaker in five control and five treatment studies in order to assess the extent of adaptation in eight normal young men to a week of night work. In the control studies, on the sixth consecutive night of sedentary work in ordinary light (approximately 150 lux), the mean (+/- SEM) nadir of the endogenous temperature cycle continued to occur during the night (at 3:31 +/- 0:56 hours), indicating a lack of circadian adaptation to the nighttime work schedule. In contrast, the subjects in the treatment studies were exposed to bright light (7000 to 12,000 lux) at night and to nearly complete darkness during the day, and the temperature nadir shifted after four days of treatment to a significantly later, midafternoon hour (14:53 +/- 0:32; P less than 0.0001), indicating a successful circadian adaptation to daytime sleep and nighttime work. There were concomitant shifts in the 24-hour patterns of plasma cortisol concentration, urinary excretion rate, subjective assessment of alertness, and cognitive performance in the treatment studies. These shifts resulted in a significant improvement in both alertness and cognitive performance in the treatment group during the night-shift hours. We conclude that maladaptation of the human circadian system to night work, with its associated decline in alertness, performance, and quality of daytime sleep, can be treated effectively with scheduled exposure to bright light at night and darkness during the day.

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  • Chronic light exposure at the wrong time, at night during shift work for example, may contribute to shifts of the circadian clock phase, dependent on duration, wavelength, and intensity of light.

    “Chronic light exposure at the wrong time, at night during shift work for example, may contribute to shifts of the circadian clock phase 59, dependent on duration, wavelength, and intensity of light 60.”

    From The inner clock-Blue light sets the human rhythm (2019) · cites this paper as [59]

  • Appropriately timed light exposure and/or melatonin intake can entrain the central pacemaker to an inverted (relative to the solar day) sleep/wake cycle in humans.

    “Researchers have demonstrated in humans that appropriately timed light exposure and/or melatonin intake can entrain the central pacemaker to an inverted (relative to the solar day) sleep/wake cycle (Boivin and James, 2002; Crowley et al., 2003; Czeisler et al., 1990; Smith et al., 2009).”

    From The impact of the circadian timing system on cardiovascular and metabolic function (2012) · cites this paper as Czeisler et al., 1990

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Research works printed but not linked: 16

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  6. [16]16. Shift Work Committee, Japan Association of Industrial Health. Opinion on night work and shift work. J Sci Labour (Jap) 1979; 55:1-37.
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  8. [26]26. Wever R. Zur zeitgeber-staerke eines licht-dunkel-wechels fuer die circadiane periodik des menschen. Eur J Physiol 1970; 321:133-42.
  9. [30]30. Czeisler CA, Brown EN, Ronda JM, Kronauer RE, Richardson GS, Freitag WO. A clinical method to assess the endogenous circadian phase (ECP) of the deep circadian oscillator in man. Sleep Res 1985; 14:295.
  10. [32]32. Czeisler CA. Internal organization of temperature, sleep-wake, and neuroendocrine rhythms monitored in an environment free of time cues. (Ph.D. thesis. Stanford, Calif.: Stanford University, 1978.)
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  13. [48]48. Dijk DJ, Beersma DG, Daan S, Lewy AJ. Bright morning light advances the human circadian system without affecting NREM sleep homeostasis. Am J Physiol 1989; 256:R106-R111.
  14. [50]50. Eastman CI. Bright light in work-sleep schedules for shift workers: application of circadian rhythm principles. In: Rensing L, an der Heiden U, Mackey MC, eds. Temporal disorder in human oscillatory systems. New York: Springer-Verlag, 1987:176-85.
  15. [52]52. Drennan M, Kripke DF, Gillin JC. Bright light can delay human temperature rhythm independent of sleep. Am J Physiol 1989; 257:R136R141.
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Authors
Czeisler, C. A., Johnson, M. P., Duffy, J. F., Brown, E. N., Ronda, J. M., & Kronauer, R. E.
Affiliations
Brigham and Women's Hospital (US)
ORCID
Venue
New England Journal of Medicine
Publisher
Massachusetts Medical Society
Published
1990-05-03
Volume
322
Issue
18
Pages
1253-1259
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
DOI
10.1056/nejm199005033221801
OpenAlex
W1987796397
Cited by
580
References
36
Citations by year
2026: 1 · 2025: 8 · 2024: 8 · 2023: 10 · 2022: 12 · 2021: 10 · 2020: 11 · 2019: 13 · 2018: 15 · 2017: 11 · 2016: 12 · 2015: 7 · 2014: 14 · 2013: 24 · 2012: 20
FWCI
33.46
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health (2s07rr005950-07)
  • National Institute on Aging (R01AG006072)
  • National Center for Research Resources (5-MO1-RR00888, 2-S07-RR05950)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
Keywords
night work, circadian misalignment, circadian adaptation, bright light exposure, darkness exposure, circadian pacemaker, body temperature rhythm, plasma cortisol, urinary excretion, alertness, cognitive performance, shift work
MeSH terms
Adaptation, Physiological, Adult, Biological Clocks, Body Temperature, Circadian Rhythm, Darkness, Environmental Exposure, Humans, Light, Male, Sleep, Work, Work Schedule Tolerance

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