Sleep is a common phenomenon in the animal world and at the same time very mysterious. Some scientists think, that it simply rests the body. However, the authors of the article in the latest issue of the weekly “Public Library of Science” they think, that the brain needs sleep for such vital functions, like remembering or forgetting. Chiara Cirelli and Guido Tononi of the University of Wisconsin in the United States analyze the latest state of sleep research. The researchers emphasize, that finding one, the primary function of sleep is extremely difficult. “It is a bit of a search for a mythological phoenix” – they write. Some scientists think so, that dream, as lack of exercise, it serves only for the rest of the body, and besides, it has no function. The authors call this position “the null hypothesis”. In their opinion, they should be rejected. They resemble, that dolphins developed the ability to fall asleep and swim at the same time. The cerebral hemispheres alternately fall asleep in them – once one, the second time. During this time, one eye is closed, and one is open. If only the rest of the body were to be rested, dolphins would not develop such a specialization. “All animals are asleep. There is no unequivocal evidence for the existence of the species, who would not be able to sleep” – scientists emphasize. Sleep is closely related to the work of the brain. Sleep deprivation leads to cognitive impairment – thinking or memory, and in extreme cases – to death, which has been observed in many species of animals. “People deprived of sleep for a long time can fall asleep even in extremely dangerous circumstances” – scientists write. As Cirelli explains, sleep is the price, what you pay for it, that the next day the brain is plastic. After a day of intensive study, the synapses are there “overloaded”. Sleep allows you to bring their activity down to the baseline level. Synapses are the connections that form between cells. Their formation and activity are related to the learning process. As the authors emphasize, the brain consumes 80 proc. energy to keep synapses active.
Sleep can also be important for consolidating fresh memories and forgetting random ones, irrelevant impressions from the previous day. This creates a place for new impressions. This is why brain waves are so intense during certain phases of sleep – researchers emphasize.
Sleep is not only about rest
