Circadian rhythms in cognitive performance: methodological constraints, protocols, theoretical underpinnings

Physiol Behav. 2007 Feb 28;90(2-3):196-208. doi: 10.1016/j.physbeh.2006.09.009. Epub 2006 Oct 19.


The investigation of time-of-day effects on cognitive performance began in the early days of psychophysiological performance assessments. Since then, standardised, highly controlled protocols (constant routine and forced desynchrony) and a standard performance task (psychomotor vigilance task) have been developed to quantify sleep-wake homeostatic and internal circadian time-dependent effects on human cognitive performance. However, performance assessment in this field depends on a plethora of factors. The roles of task difficulty, task duration and complexity, the performance measure per se, practice effects, inter-individual differences, and ageing are all relevant aspects. Therefore, well-defined theoretical approaches and standard procedures are needed for tasks pinpointing higher cortical functions along with more information about time-dependent changes in the neural basis of task performance. This promises a fascinating challenge for future research on sleep-wake related and circadian aspects of different cognitive domains.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Behavioral Research / methods
  • Circadian Rhythm / physiology*
  • Cognition / physiology*
  • Humans
  • Models, Neurological
  • Psychomotor Performance / physiology*
  • Sleep / physiology*
  • Wakefulness / physiology*