Influence of chronotype and social zeitgebers on sleep/wake patterns

Influence of chronotype and social zeitgebers on sleep/wake patterns

Autor Korczak, A.l. Google Scholar
Martynhak, B.j. Google Scholar
Pedrazzoli, Mario Autor UNIFESP Google Scholar
Brito, A.f. Google Scholar
Louzada, F.m. Google Scholar
Instituição Universidade Federal do Paraná Departamento de Fisiologia Setor de Ciências Biológicas
Universidade Federal de São Paulo (UNIFESP)
Resumo Inter-individual differences in the phase of the endogenous circadian rhythms have been established. Individuals with early circadian phase are called morning types; those with late circadian phase are evening types. The Horne and Östberg Morningness-Eveningness Questionnaire (MEQ) is the most frequently used to assess individual chronotype. The distribution of MEQ scores is likely to be biased by several fact, ors, such as gender, age, genetic background, latitude, and social habits. The objective of the present study was to determine the effect of different social synchronizers on the sleep/wake cycle of persons with different chronotypes. Volunteers were selected from a total of 1232 UFPR undergraduate students who completed the MEQ. Thirty-two subjects completed the study, including 8 morning types, 8 evening types and 16 intermediate types. Sleep schedules were recorded by actigraphy for 1 week on two occasions: during the school term and during vacation. Sleep onset and offset times, sleep duration, and mid-sleep time for each chronotype group were compared by the Mann-Whitney U-test separately for school term and vacation. School term and vacation data were compared by the Wilcoxon matched-pair test. Morning types showed earlier sleep times and longer sleep duration compared with evening types (23:00 ± 44 and 508.9 ± 50.27 vs 01:08 ± 61.95 and 456.44 ± 59.08, for the weekdays during vacation). During vacation, the subjects showed later sleep times, except for the morning types, who did not exhibit differences for sleep onset times. The results support the idea that social schedules have an impact on the expression of circadian rhythmicity but this impact depends on the individual chronotype.
Assunto Chronotype
Sleep/wake cycle
Morning types
Evening types
Circadian rhythm
Social zeitgebers
Idioma Inglês
Data 2008-10-01
Publicado em Brazilian Journal of Medical and Biological Research. Associação Brasileira de Divulgação Científica, v. 41, n. 10, p. 914-919, 2008.
ISSN 0100-879X (Sherpa/Romeo)
Editor Associação Brasileira de Divulgação Científica
Extensão 914-919
Direito de acesso Acesso aberto Open Access
Tipo Artigo
SciELO S0100-879X2008001000014 (estatísticas na SciELO)

Mostrar registro completo

Arquivos deste item

Nome: S0100-879X2008001000014.pdf
Tamanho: 542.3Kb
Formato: PDF

Este item aparece na(s) seguinte(s) coleção(s)