Time-of-day effects on cognition in preadolescents: a trails study

Chronobiol Int. 2010 Oct;27(9-10):1870-94. doi: 10.3109/07420528.2010.516047.

Abstract

Cognitive performance fluctuates during the day due to diurnal variations in alertness level. This study examined: (1) whether cognitive performance in school-aged children is affected by time-of-day; (2) which functional domains are particularly vulnerable to time-of-day effects; and (3) whether the effects are more pronounced for cognitively more demanding tasks or task conditions. Children, aged 10-12 yrs, were randomly assigned to a test session starting either at 08:30 (n = 802), 10:00 (n = 713), or 13:00 h (n = 652). Speed and accuracy of information processing were evaluated by tasks that assess input-related cognitive processes (e.g., stimulus encoding), central cognitive processes (e.g., working memory, sustained attention), and output-related processes (e.g., response organization) using the Amsterdam Neuropsychological Tasks program. Time-of-day effects in children were identified in specific neurocognitive domains, such as visuospatial processing and working memory, but only under cognitively more demanding task conditions. Sustained attention showed a speed-accuracy tradeoff with increased slowness and lapses in the early morning, but with better feedback responsiveness and perceptual sensitivity than in the early afternoon. Furthermore, there was a significant interaction of time-on-task with time-of-day for tempo, with the afternoon group increasing in tempo with time-on-task, and the early-morning group first showing a slowing of tempo with time-on-task, followed at the end of the task by a speed increase towards the initial levels. To conclude, the authors found time-of-day effects in preadolescents, which were confined to cognitively more demanding tasks tapping input-related and central cognitive processes.

MeSH terms

  • Attention / physiology
  • Child
  • Circadian Rhythm / physiology*
  • Cognition / physiology*
  • Demography
  • Educational Status
  • Fathers
  • Female
  • Humans
  • Male
  • Memory / physiology
  • Mothers
  • Netherlands
  • Neuropsychological Tests
  • Occupations
  • Puberty / physiology
  • Puberty / psychology
  • Rural Population
  • Task Performance and Analysis*
  • Urban Population