Second international School On Mind, Brain And Education

2007, May 22-26

Basic and Applied Topics
in Biological Rhythms and Learning

Directors: Antonio M. Battro and Kurt W. Fischer
Program officer: María Lourdes Majdalani

Abstract: Claudia Moreno

Early working students chronotypes seem to be more tolerant to a double-burden than late types
Introduction: Adolescents who work during the day and study at night may suffer strong interference of their schedules on their individual sleep preferences. Previous studies showed a cumulative sleep debt in working students throughout the workweek (Teixeira et al, 2004, 2007). Considering the relationship between chronotype and sleep timing among adolescents, the consequences of this mentioned sleep deficit could be reflected on characteristics of sleep and psychological wellbeing. Objectives: The aim of this present study is to verify the correlation of morningness and characteristics of sleep and psychological wellbeing, comparing working and non-working students. Methods: The study group consisted of working (n=51) and non-working (n=41) students, aged 14-21 yrs. The high-school students attended evening classes (19:00-22:30h) at a public school in São Paulo, Brazil. The students filled out a morningness-eveningness questionnaire (Horne & Östberg, 1976), and a sleep diary (during one week) with visual analogue scales related to sleep quality, mood, and difficulty to wake up/to fall asleep. The correlations were calculated through the Spearman coefficient. Results: It was found a significant statistical correlation between chronotype and difficulty to wake up on Sundays among non-working students (R= 0.32; p<0.05). There was also found a significant statistical correlation between the choronotype and mood on Sundays among working students (R= 0.32; p<0.05). The earlier type the less difficulty to wake up on Saturdays (R=0.39; p<0.01) and during three work days (from Tuesday to Thursday) among working students (R=0.34; p<0.05). Discussion and conclusion: Working students have to follow a stricter routine of their sleep-wake cycle than non-working students, due to their school-work duties. Although attending evening classes, early types seem to be more tolerant to a double-burden (work and school) than late types. These findings can be related to the higher sleepiness in the evenings among working students found on the previous study. It also seems that the sleep debt along the workweek lead the late types to have more difficulties to wake up early in the morning in order to work.