Circadian rhythms and sleep are fundamental biological processes integral to human
health. Their disruption is associated with detrimental physiological consequences …

The interest in the systematic study of the circadian typology (CT) is relatively recent and has
developed rapidly in the two last decades. All the existing data suggest that this individual …

Patterns of daily human activity are controlled by an intrinsic circadian clock that promotes∼
24 hr rhythms in many behavioral and physiological processes. This system is altered in …

Mammalian circadian rhythms are controlled by endogenous biological oscillators, including
a master clock located in the hypothalamic suprachiasmatic nuclei (SCN). Since the period …

Melatonin, the neurohormone of the pineal gland, is also produced by various other tissues
and cells. It acts via G protein-coupled receptors expressed in various areas of the central …

The circadian nature of physiology and behavior is regulated by a circadian clock that
generates intrinsic rhythms with a periodicity of approximately 24 h. The mammalian …

Human behavior shows large interindividual variation in temporal organization. Extreme
“larks” wake up when extreme “owls” fall asleep. These chronotypes are attributed to …

Sleep deprivation is associated with considerable social, financial, and health-related costs,
in large measure because it produces impaired cognitive performance due to increasing …

Much of the current science on, and mathematical modeling of, dynamic changes in human
performance within and between days is dominated by the two-process model of sleep …

Humans show large inter-individual differences in organising their behaviour within the 24-h
day—this is most obvious in their preferred timing of sleep and wakefulness. Sleep and …