Human brain aging is characterized by the gradual deterioration of its function and structure, affected by the interplay of a multitude of causal factors. The sleep, a periodically repeating state of reversible unconsciousness characterized by distinct electrical brain activity, is crucial for maintaining brain homeostasis. Indeed, insufficient sleep was associated with accelerated brain atrophy and impaired brain functional connectivity. Concurrently, alteration of sleep-related transient electrical events in senescence was correlated with structural and functional deterioration of brain regions responsible for their generation, implying the interconnectedness of sleep and brain structure. This review discusses currently available data on the link between human brain aging and sleep derived from various neuroimaging and neurophysiological methods. We advocate the notion of a mutual relationship between the sleep structure and age-related alterations of functional and structural brain integrity, pointing out the position of high-quality sleep as a potent preventive factor of early brain aging and neurodegeneration. However, further studies are needed to reveal the causality of the relationship between sleep and brain aging.

1st Department of Neurology Faculty of Medicine University Hospital of St Anne and Masaryk University Brno Czechia

Center for Magnetic Resonance Research University of Minnesota Minneapolis MN United States

Department of Neurology 1st Faculty of Medicine General University Hospital Prague and Charles University Prague Czechia

Department of Neurology Faculty of Medicine University Hospital Brno and Masaryk University Brno Czechia

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Sleep quality and the integrity of ascending reticular activating system - A multimodal MRI study