Cited by 571Circadian rhythm and melatoninSleep and related disordersSleep and Work-Related Fatigue

Association of intrinsic circadian period with morningness–eveningness, usual wake time, and circadian phase.

Duffy, Jeanne F., Rimmer, David W., Czeisler, Charles A.·2001·Behavioral Neuroscience

Abstract

The biological basis of preferences for morning or evening activity patterns ("early birds" and "night owls") has been hypothesized but has remained elusive. The authors reported that, compared with evening types, the circadian pacemaker of morning types was entrained to an earlier hour with respect to both clock time and wake time. The present study explores a chronobiological mechanism by which the biological clock of morning types may be set to an earlier hour. Intrinsic period, a fundamental property of the circadian system, was measured in a month-long inpatient study. A subset of participants also had their circadian phase assessed. Participants completed a morningness-eveningness questionnaire before study. Circadian period was correlated with morningness-eveningness, circadian phase, and wake time, demonstrating that a fundamental property of the circadian pacemaker is correlated with the behavioral trait of morningness-eveningness.

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Crossref · 10.1037/0735-7044.115.4.895

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Authors
Duffy, J. F., Rimmer, D. W., & Czeisler, C. A.
Affiliations
Brigham and Women's Hospital (US)
Venue
Behavioral Neuroscience
Published
2001
Volume
115
Issue
4
Pages
895-899
ISSN
  • 0735-7044 (ISSN-L)
  • 1939-0084
OpenAlex
W4233060373
Cited by
571
References
44
Citations by year
2026: 13 · 2025: 17 · 2024: 30 · 2023: 12 · 2022: 20 · 2021: 18 · 2020: 37 · 2019: 31 · 2018: 32 · 2017: 31 · 2016: 24 · 2015: 28 · 2014: 34 · 2013: 32 · 2012: 27
FWCI
3.09
Type
journal article
Language
en
Open access
closed
Locations
  • Behavioral Neuroscience (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institute on Aging (P01AG009975, P01 AG-09975)
  • National Heart, Lung, and Blood Institute (T32 HL 07901, T32HL007901)
  • National Center for Research Resources (M01 RR 02635, M01RR002635)
Topics
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
Keywords
circadian period, chronotype, circadian phase, chronobiology
MeSH terms
Adult, Biological Clocks, Body Temperature, Body Temperature Regulation, Circadian Rhythm, Humans, Individuality, Male, Surveys and Questionnaires, Self-Assessment, Sleep

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