Related Experiment Video
Updated: May 6, 2026
Human Circadian Phenotyping and Diurnal Performance Testing in the Real World
Published on: April 7, 2020
Sleep/wake patterns and circadian typology in preschool children based on standardized parental self-reports
Yuriko Doi1, Kaneyoshi Ishihara, Makoto Uchiyama
1National Institute of Public Health, Area on Epidemiological Research , Wako , Japan .
Insights
Preschool children show delayed sleep/wake times on weekends. Chronotypes influence sleep patterns, with evening types having later sleep, and napping may offset weekday sleep deficits.
Area of Science:
- Pediatric Sleep Medicine
- Chronobiology
- Developmental Psychology
Background:
- Understanding sleep patterns in preschool children is crucial for development.
- Circadian typology, or chronotype, influences daily biological rhythms.
- Previous research has focused more on older children and adolescents.
Purpose of the Study:
- To investigate sleep/wake patterns and circadian typology in Japanese preschool children.
- To examine age-related and sex-related differences in sleep.
- To explore the association between chronotype and lifestyle factors.
Main Methods:
- A standardized parental self-reporting questionnaire was used.
- Data collected from 383 preschool children (193 boys, 190 girls) aged 4-6 years.
- Study conducted in the Tokyo metropolitan area from June to July 2012.
Main Results:
- Sleep/wake timing was delayed on weekends compared to weekdays across all ages.
- Sleep duration was longer in 4-year-olds than 5-6 year-olds.
- Chronotype distribution was 36.3% morning, 48.8% neither, and 11.2% evening, independent of sex or age.
- Evening chronotypes exhibited delayed sleep/wake timing and altered sleep durations on weekdays.
- Chronotypes were associated with parental diurnal preferences and lifestyle, but not with sex, age, or environmental factors like morning sunlight exposure.
Conclusions:
- Preschool children exhibit distinct sleep/wake patterns and circadian typology, similar to older age groups but to a lesser extent.
- Napping may play a role in compensating for weekday sleep deficits.
- Chronotype is linked to sleep timing and duration, influenced by parental lifestyle, suggesting potential for targeted interventions.
Abstract:
We studied the sleep/wake patterns and circadian typology of Japanese preschool children living in the Tokyo metropolitan area (193 boys and 190 girls, 4-6 years of age) from June to July 2012 based on a standardized parental self-reporting questionnaire. Our major findings are as follows: (1) sleep/wake timing was delayed, and the duration of nocturnal sleep (sleep period as well as time in bed) increased from that on scheduled days (weekdays) to that on free days (weekends) for all ages. (2) The duration of daily sleep (24 h), including daytime nap, was longer for 4-year-old children compared with that in 5- to 6-year-old children, but not significantly different between scheduled and free days within each age group. (3) The distribution of chronotypes was 36.3% for morning (M)-type, 48.8% for neither (N)-type and 11.2% for evening (E)-type, and this distribution was independent of sex or age. (4) Sleep/wake timing delays were observed from M-type and N-type to E-type during scheduled and free days. (5) The duration of nocturnal sleep decreased but increased for 24-h sleep time from M-type and N-type to E-type on scheduled days. (6) Sleep durations did not differ among chronotypes on free days. (7) Chronotypes were associated with parents' diurnal preferences, mealtimes and attendance at kindergartens or childcare centers but not with sex, age, season of birth, exposure to multimedia or exposure to morning sunlight in their bedrooms. When these results were compared with those for older children and adolescents, similar sleep/wake patterns and circadian typology were observed, although to a lesser degree, in children as young as 4-6 years of age. Napping may compensate, in part, for an accumulated weekday sleep deficit. The distribution of chronotypes was associated with differences in sleep/wake timing and duration and was influenced by the parents' diurnal preferences and lifestyles. Further research on preschool children is required to investigate whether circadian typology affects their behavioral, emotional and cognitive development.
Related Concept Videos
02:19Circadian Rhythms and Gene Regulation
02:19Circadian Rhythms and Gene Regulation
01:15REM Sleep Behavior Disorder
RBD is significantly associated with...
01:24Sleep-Wake Cycles
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
01:27Parenting Styles
Authoritarian Parenting
This style is strict and controlling, with little room for open dialogue. Authoritarian parents demand obedience and often enforce rules with minimal warmth. Children raised this way may lack social skills and initiative, usually comparing themselves to others unfavorably.
Authoritative...
01:11Understanding Sleep
The circadian rhythm, a nearly 24-hour cycle, is deeply influenced by environmental light cues. Light exposure directly affects the hypothalamus, which in turn regulates...