Model-based simulations of weekday and weekend sleep times self-reported by larks and owls

A model of sleep-wake regulatory process was applied to examine several common believes associated with the so-called "social jetlag", e.g. 1) sleep lost on weekdays due to the scheduled early wakeups might be partly recouped by getting extra sleep on weekends and 2) the weekday sleep loss is greater in evening- than in morning-oriented individuals. Weekday-weekend sleep times reported in 19 previously published papers for 20 samples of morning- and evening-oriented individuals were utilized as an input to the model. The results of statistical analyses and simulations of these times suggested that 1) sleep cannot be caught up on weekends and 2) evening- and morning-oriented individuals are not, in general, dissimilar on the amount of weekday sleep. We concluded that chronobiologial mechanisms underlying "social jetlag" require rethinking and that studying mathematical models of sleep-wake regulatory process allow the quantitative predictions about weekday sleep loss in different ages and diurnal types.