Sleep

Sleep is a generally recurring state characterized through absent or reduced consciousness, associatively suspended sensory activity and inactivity of nearly all voluntary muscles. The neuroscience of sleep is the study of the neuroscientific and physiological basis of the nature of sleep and its functions. Usually, sleep has been studied as category of medicine and psychology. The learning of sleep from a neuroscience perspective grew to prominence with advances in proliferation and technology of neuroscience research from the second half of the 20th century.

The reality that organisms spend about a third of their time in sleep and which sleep deprivation can have disastrous effects ultimately leading to death demonstrate the importance of sleep. For a phenomenon so important the mechanisms and purposes of sleep are only partially understood so much in which somebody quipped the only known function of sleep is to cure sleepiness. Moreover, the development of improved imaging methods like EEG, PET and fMRI, along with high computational power have led to an increasingly greater understanding of the mechanisms underlying sleep.