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Insights from studying human sleep disorders


Problems with sleep are one of the commonest reasons for seeking medical attention. Knowledge gained from basic research into sleep in animals has led to marked advances in the understanding of human sleep, with important diagnostic and therapeutic implications. At the same time, research guided by human sleep disorders is leading to important basic sleep concepts. For example, sleep may not be a global, but rather a local, brain phenomenon. Furthermore, contrary to common assumptions, wakefulness, rapid eye movement (REM) and non-REM sleep are not mutually exclusive states. This striking realization explains a fascinating range of clinical phenomena.

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Figure 1: Ambiguous sleep in a patient with narcolepsy.
Figure 2: A sleepwalking episode.
Figure 3: The rapid evolution of a sleep terror episode.
Figure 4: REM sleep behaviour disorder.
Figure 5: REM sleep without atonia in a patient with REM sleep behaviour disorder.


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Correspondence to Mark W. Mahowald.

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The authors declare competing financial interests: Mark W. Mahowald - Research/Grant Support: Takeda, Cephalon, Lorex, Neurocrine, GalaxoKlineSmith, Pharmacia, Pfizer, Boehringer Ingelham, Aventis .

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Abnormal REM sleep behaviours documented in older men with 'REM sleep behaviour disorder'during sleep laboratory video-polysomnographic monitoring at the Minnesota Regional Sleep Disorders Center. (MPG 5362 kb)

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Mahowald, M., Schenck, C. Insights from studying human sleep disorders. Nature 437, 1279–1285 (2005).

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