Delaying school starting time by one hour: some effects on attention levels in adolescents

J Clin Sleep Med. 2011 Apr 15;7(2):137-43.


Study objective: The purpose of the study was to assess the attention level of middle-school students by providing a group of students with the opportunity for an additional one hour of sleep in the morning by delaying school starting time by one hour, as compared to another group received no additional sleep.

Method: For the first week of the study, the school starting time was delayed 1 h for the experimental group (N = 26). In the second week, these students returned to their regular school schedule. A control group (N = 21) remained on their regular schedule for these 2 weeks. Both groups were tested at the end of each week with 2 measures to assess their attention.

Results: The results showed that in the first week the experimental group slept an average of 55 minutes longer each night, for 5 nights (total 275 minutes). Students who slept longer performed better in measures of attention as assessed by the "Mathematics Continuous Performance Test" and the "d2 Test of Attention," indicating better performance in attention level, impulsivity, and the rate of performance.

Conclusions: The study strongly recommends that middle schools should consider delaying the school starting time by at least one hour. Such a change could enhance students' cognitive performance by improving their attention level, increasing rate of performance, as well as reducing their mistakes and impulsivity.

Keywords: Adolescent; attention; delayed school; short night sleep.

Publication types

  • Clinical Trial

MeSH terms

  • Adolescent
  • Attention*
  • Educational Status
  • Female
  • Humans
  • Male
  • Schools / organization & administration*
  • Sleep*
  • Time Factors