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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Available from: Marcos G Frank, Apr 05, 2014
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    • "Previous studies have established a correlation between neural restoration and sleep regularity. Other forms of restoration in the body also have been observed, but much less evidence supports the notion that sleep provides primarily somatic as opposed to neural restoration [1]. A growing consensus suggests that a major benefit of sleep involves ongoing support for neuronal function in the brain. "
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    Sleep Medicine 03/2014; 15(3). DOI:10.1016/j.sleep.2013.10.017 · 3.10 Impact Factor
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    • "Sleep is a complex physiological process and still remains one of the great mysteries of science [1] [2]. Hypotheses for the function of sleep include somatic, metabolic and cellular theories, as well as brain-specific alterations affecting synaptic plasticity and leading to synaptic downscaling [3e10]. "
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    • "Several studies have examined the regulatory mechanisms of sleep and the impact of sleep deprivation (SD) on biological systems. Sleep facilitates learning and memory and, consequently, synaptic plasticity (for reviews, see Frank, 2006; Walker, 2008). Sleep loss induces changes in behavior, as well as in synaptic and membrane excitability in the hippocampus and cortex (McDermott et al., 2003; Winters et al., 2011). "
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