| dc.description.abstract | Sleep plays a key role in the cognitive function of all higher vertebratesand as of quite recently,invertebrates too.Thedefinite reason for its function anddifferent stages it not yet completely understood, but the newest research and research methods are discovering more and more than what we knew just a few years ago. The discovery of the electroencephalogram(EEG) in 1924 was revolutionary within the science of sleep physics because it made it possible to study the brain-wavechanges of animals and humans during sleep, and how they change throughout the night. | en_US |
