Article

The mystery of sleep function: current perspectives and future directions.

Department of Neuroscience, University ofPennsylvania, Philadelphia, PA 19014 , USA.
Reviews in the neurosciences (Impact Factor: 3.31). 02/2006; 17(4):375-92. DOI: 10.1515/revneuro.2006.17.4.375
Source: PubMed

ABSTRACT The function of sleep is one of the most persistent and perplexing mysteries in biology. Many theories have been proposed to explain why we sleep, but most account for only a portion of sleep behavior and very few enjoy strong experimental support. A critical review of current findings leads to the following conclusions. Sleep is for the brain rather than the body, and the neural process most impacted by sleep is cognition. Sleep may influence cognition in many ways, including the removal of a toxic byproduct of wakefulness, or the restoration of neural substrates needed for mental processes. The evidence for these possibilities, however, is weak or equivocal. On the other hand, converging lines of evidence support the hypothesis that sleep promotes brain plasticity.

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