June 7, 2005
Sleep Loss Affects High Schoolers
CHICAGO—Current high school start times deprive adolescents of sleep and force students to perform academically in the early morning, a time of day when they are at their worst, according to a study in the June issue of the journal Pediatrics.
Results from high school senior sleep-wake diaries kept for the study also showed that adolescents lost as much as two hours of sleep per night during the school week, but weekend sleep times during the school year were similar to those in summer.
The study was a collaborative project involving researchers at the Feinberg School of Medicine and the Center for Sleep and Circadian Biology at Northwestern University and faculty members, students, and parents from Evanston (Illinois) Township High School (ETHS). The students were advanced placement biology students who helped conduct the study and analyze the collected data.
Martha Hansen, advanced placement biology teacher and science department chair at ETHS, headed the project in collaboration with Feinberg School faculty members Margarita L. Dubocovich, PhD, professor of molecular pharmacology and biological chemistry and of psychiatry and behavioral sciences, and Phyllis C. Zee, MD, professor of neurology.
The study assessed the impact of sleep loss after the start of school on cognitive performance and mood and examined the relationship of weekday sleep to weekend sleep in adolescents.
The study also showed that exposure to bright light in the morning did not modify students’ sleep-wake cycle or improve daytime performance during weekdays, probably because of their strict school schedule. All students performed better in the afternoon than in the morning. Students in early morning classes reported being wearier, less alert, and having to expend greater effort.
Potential solutions to this problem could be solved by changing school start times and giving standardized tests later in the day, the authors suggested.
For example, classes at ETHS start at 8:05 a.m. and run until 3:35 p.m.—one of the longest school days in Illinois. Many high schools in the country have start times of 7:15 or 7:30 a.m. In addition, almost all standardized tests in high school begin at 8 a.m. Since this is when adolescents show their poorest performance levels, a change is clearly needed and would be relatively easy to negotiate, the researchers suggest.
While the authors emphasized that more research on adolescent circadian rhythms is needed, they also believe that all groups dealing with adolescents—pediatricians, parents, teachers, and teenagers themselves—need to be aware of adolescents’ lifestyle patterns and the unusual weekday/weekend sleep phenomena.
“Knowledge of adolescent circadian rhythms could promote better family relationships if parents understood that sleeping late on weekends is part of their children’s inborn cycle and not ‘lazy’ or antisocial behavior,” the researchers said.
Finally, this sleep study forged a collaboration between high school students and faculty members in which everyone learned and benefited.
“Students were able to learn about the process of collecting and analyzing data and to discover more about the fascinating topic of themselves,” the authors said.
Other researchers on the study were Imke Janssen, statistician and ETHS parent, and Adam Schiff, a former ETHS student now in medical school.