Cerebral mechanisms underlying cognition-related time-of-day modulations in healthy ageing: a functional neuroimaging approach

In humans, homeostatic and circadian sleep-wake regulatory processes are continuously working in harmony or in opposition to each other to allow maintenance of sleep and wakefulness states at appropriate time points within the 24 hour light-dark cycle. Importantly, sleep patterns change substantially and continuously with age across adulthood. Our proposal aims at combining signals from a series of techniques for an integrative understanding of the cerebral mechanisms underlying age-related alterations in circadian arousal promotion directly impacting on higher order cognitive behaviours. The investigation of such mechanisms may appear decisive in our aging society in which flexible working hours outside of the normal “day work” hours are increasingly required.