Circadian rhythms, with a period close to 24h, are observed in most living organisms and play a fundamental role in the adaptation
of these organisms to their environment. Since several years, remarkable advances have permitted to largely unravel the molecular
bases of circadian rhythms in mammals and more particularly in humans. Computational models were thus developped in order to
analyze and clarify the regulatory network at the origin of circadian rhythms as well as the dynamical bases of physiological
disorders associated with a dysfunction of the circadian clock. In this context, we mainly focus on the link between the circadian clock
and sleep phase disorders, (bipolar or seasonal) depressions as well as the effect of jet lag and shift work.