page_title: Neuroscience of sleep
section_title: Ontogeny and phylogeny of sleep
hierarchical_section_title: Neuroscience of sleep / Ontogeny and phylogeny of sleep
caption_attribution_description: English: White Tiger Sleep
context_page_description: The neuroscience of sleep is the study of the neuroscientific and physiological basis of the nature of sleep and its functions. Traditionally, sleep has been studied as part of psychology and medicine. The study of sleep from a neuroscience perspective grew to prominence with advances in technology and proliferation of neuroscience research from the second half of the twentieth century.
  The importance of sleep is demonstrated by the fact that organisms daily spend hours of their time in sleep, and that sleep deprivation can have disastrous effects ultimately leading to death. For a phenomenon so important, the purposes and mechanisms of sleep are only partially understood, so much so that as recently as the late 1990s it was quipped: "The only known function of sleep is to cure sleepiness". However, the development of improved imaging techniques like EEG, PET and fMRI, along with high computational power have led to an increasingly greater understanding of the mechanisms underlying sleep.
  The fundamental questions in the neuroscientific study of sleep are:
  What are the correlates of sleep i.e. what are the minimal set of events that could confirm that the organism is sleeping?
context_section_description: The questions of how sleep evolved in the animal kingdom and how it developed in humans are especially important because they might provide a clue to the functions and mechanisms of sleep respectively.
caption: Animal Sleep: Sleeping white tiger
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