Micheline MAIRE1, Carolin F. REICHERT1, Christina SCHMIDT*
Psychiatric University Clinics, Basel, Switzerland
In human beings, homeostatic and circadian sleep-wake regulatory processes are working together for the maintenance of sleep and wakefulness at appropriate times within the 24-hour light-dark cycle. The interaction between these processes also determines time-of-day modulations in sleepiness and alertness levels, and affects performance in a series of cognitive tasks. Besides, individuals differ in the synchronization of a great number of behaviors, ranging from preferred timing for sleep and wakefulness to habitual sleep duration or differences in sleep depth and sleep structure. Genetic factors have been shown to contribute substantially to inter-individual differences in most of these variables. Trait-like variability has also been suggested in the cerebral bases underlying cognitive effort under adverse circadian phase and sleep deprivation. The field of human sleep and chronobiology research has been shown suitable for translational research such that a multitude of therapeutic tools have been derived, which start to be recognized in sleep medicine and psychiatry. Regarding the presence of prominent inter-individual variability in sleep-wake behaviors and its impact on cognition and subjective wellbeing, individually tailored schemes might be more accurate, also for the prediction of treatment efficiency at the clinical level.
Keywords: sleep, circadian rhythms, inter-individual differences, cognitive performance