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Sleep viewed as a state of adaptive inactivity

Nature Reviews Neuroscience volume 10, pages 747753 (2009) | Download Citation

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Abstract

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Sleep is often viewed as a vulnerable state that is incompatible with behaviours that nourish and propagate species. This has led to the hypothesis that sleep has survived because it fulfills some universal, but as yet unknown, vital function. I propose that sleep is best understood as a variant of dormant states seen throughout the plant and animal kingdoms and that it is itself highly adaptive because it optimizes the timing and duration of behaviour. Current evidence indicates that ecological variables are the main determinants of sleep duration and intensity across species.

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  • 06 August 2009

    In the version of this article initially published online, figure 2 read "Similar phenomena seen in all other land mammals examined" in the "Comments" row of the columns headed "Cat (Felis catus)" and "Virginia opossum (Didelphis virginiana)". The error has been corrected in the HTML and PDF versions

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Acknowledgements

The author's work is supported by the Medical Research Service of the Veterans Affairs Greater Los Angeles Healthcare System, grants NS14610, HL41370, MH64109 and NSF0234687. I thank G. Barber and W. Domhoff for helpful comments.

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  1. Jerome M. Siegel is at the Department of Psychiatry, School of Medicine, University of California, Los Angeles, California 90095, USA and at Neurobiology Research (151-A3), Veterans Affairs Greater Los Angeles Healthcare System, North Hills, California 91343, USA.

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https://doi.org/10.1038/nrn2697

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