Sleep not only allows the brain to "rest", but it is also necessary for proper communication between nerve cells. As per a study conducted by a research team from the University of Camerino and published in the international scientific journal PNAS-Proceedings of the National Academy of Sciences, this is the case. The study, undertaken in partnership with researchers from the Alicante Neuroscience Institute in Spain, indicates that sleep deprivation not only causes neurons to become "tired", but also drastically inhibits the transmission of electrical signals throughout the brain. This effect is associated with a change in myelin, the membrane that envelops nerve fibers and enables the rapid and efficient communication between various brain regions. When myelin performs poorly, messages take longer to propagate, which has a direct impact on attention, coordination, and cognitive performance. The study also identifies the biochemical mechanism underlying this phenomenon: lack of sleep changes cholesterol metabolism in oligodendrocytes, which are responsible for myelin production and maintenance. Dysfunction of these cells could thus explain, at least in part, the decrease in mental and cognitive functioning reported during sleep deprivation. "Our findings," the researchers say, "show that sleep is critical not only for neuronal activity, but also for the health of the cells that support neurons. This study helps to explain why sleep deprivation has such a significant impact on our cognitive performance". The research provides novel insights into the role of sleep in brain health and has the potential to have significant future implications for the prevention and management of cognitive disorders associated with sleep deprivation.