Cited by 273Circadian rhythm and melatoninSleep and related disordersSleep and Wakefulness Research

A Longitudinal Assessment of Sleep Timing, Circadian Phase, and Phase Angle of Entrainment across Human Adolescence

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Crowley, Stephanie J., Van Reen, Eliza, LeBourgeois, Monique K., Acebo, Christine, Tarokh, Leila, Seifer, Ronald, Barker, David H., Carskadon, Mary A.·2014·PLoS ONE

Abstract

The aim of this descriptive analysis was to examine sleep timing, circadian phase, and phase angle of entrainment across adolescence in a longitudinal study design. Ninety-four adolescents participated; 38 (21 boys) were 9-10 years ("younger cohort") and 56 (30 boys) were 15-16 years ("older cohort") at the baseline assessment. Participants completed a baseline and then follow-up assessments approximately every six months for 2.5 years. At each assessment, participants wore a wrist actigraph for at least one week at home to measure self-selected sleep timing before salivary dim light melatonin onset (DLMO) phase - a marker of the circadian timing system - was measured in the laboratory. Weekday and weekend sleep onset and offset and weekend-weekday differences were derived from actigraphy. Phase angles were the time durations from DLMO to weekday sleep onset and offset times. Each cohort showed later sleep onset (weekend and weekday), later weekend sleep offset, and later DLMO with age. Weekday sleep offset shifted earlier with age in the younger cohort and later in the older cohort after age 17. Weekend-weekday sleep offset differences increased with age in the younger cohort and decreased in the older cohort after age 17. DLMO to sleep offset phase angle narrowed with age in the younger cohort and became broader in the older cohort. The older cohort had a wider sleep onset phase angle compared to the younger cohort; however, an age-related phase angle increase was seen in the younger cohort only. Individual differences were seen in these developmental trajectories. This descriptive study indicated that circadian phase and self-selected sleep delayed across adolescence, though school-day sleep offset advanced until no longer in high school, whereupon offset was later. Phase angle changes are described as an interaction of developmental changes in sleep regulation interacting with psychosocial factors (e.g., bedtime autonomy).

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  • The shift in circadian timing during adolescence may be conserved among rodents and non-human primates.

    “In general, the timing of sleep onset and waking and other biological rhythms (for example, fluctuations in melatonin levels) is earlier relative to adults during early childhood8,9 and shifts later during adolescence, and this shift in timing may be conserved among rodents and non-human primates (NHPs)10.”
  • Early school start times, which are typically more than an hour earlier in US high schools (ages 15-18 years) than in elementary schools (ages 9-10 years) or middle schools (ages 11-13 years), may contribute to shorter sleep.

    “Early school start times, which are typically more than an hour earlier in US high schools (ages 15–18 years) than in elementary schools (ages 9–10 years) or middle schools (ages 11–13 years), may contribute to these problems of shorter sleep10,148.”
  • During adolescence, circadian rhythms naturally delay.

    “circadian rhythms naturally delay”
  • Changes in sleep/circadian timing appear to result from both phase delays in the circadian clock and a slower accumulation in homeostatic sleep drive.

    “Changes in sleep/circadian timing appear to result from both phase delays in the timing of the circadian clock (38), and a slower accumulation in homeostatic sleep drive (37).”
  • Decreased sleep duration and increased sleep disturbance may be a consequence of delayed sleep timing conflicting with school start times on weekdays, resulting in circadian misalignment and sleep loss.

    “Decreased sleep duration and increased sleep disturbance may be a consequence of delayed sleep timing, conflicting with school start times on weekdays, (typically earlier in high school than in elementary or middle school), resulting in circadian misalignment and sleep loss (38,45).”

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Authors
Crowley, S. J., Van Reen, E., LeBourgeois, M. K., Acebo, C., Tarokh, L., Seifer, R., Barker, D. H., & Carskadon, M. A.
Affiliations
  • Rush University Medical Center (US)
  • University of Colorado Boulder (US)
  • Brown University (US)
  • University of Bern (CH)
  • University of South Australia (AU)
Corresponding author
Crowley, Stephanie J.
Venue
PLoS ONE
Published
2014-11-07
Volume
9
Issue
11
Pages
e112199
ISSN
1932-6203 (ISSN-L)
OpenAlex
W2090080078
Cited by
273
References
60
Citations by year
2026: 27 · 2025: 19 · 2024: 21 · 2023: 31 · 2022: 25 · 2021: 26 · 2020: 22 · 2019: 33 · 2018: 25 · 2017: 21 · 2016: 15 · 2015: 8
FWCI
7.15
Type
journal article
Language
en
Open access
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • BORIS (University Library Bern) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • UniSA Research Outputs Repository (University of South Australia) (submittedVersion)
  • Open Access CRIS of the University of Bern
Funders
  • Brown University
  • Jazz Pharmaceuticals
  • National Institutes of Health
  • National Institute on Alcohol Abuse and Alcoholism (AA 13252, R01AA013252)
Topics
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
Keywords
sleep timing, circadian phase, adolescence, dim light melatonin onset, sleep onset, sleep offset, circadian entrainment, salivary melatonin
MeSH terms
Adolescent, Aging, Child, Circadian Rhythm, Female, Humans, Longitudinal Studies, Male, Melatonin, Saliva, Sex Characteristics, Sleep, Time Factors, Actigraphy

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