Why We Nap pp 82-101 | Cite as

The Impact of Irregular Sleep-Wake Schedules on Circadian Rhythms and the Role of “Anchor” Sleep

  • D. S. Minors
  • J. M. Waterhouse


In humans the inherent period of the internal oscillator controlling overt circadian rhythmicity is, on average, 25 hr (Wever, 1979). However, when we live under normal nychthemeral circumstances, the internal circadian oscillator is synchronized to a period of exactly 24 hr. The adjustment is achieved by means of rhythmic cues from the external world, for example, the alternation of light and dark, the sleep-wake cycle, social influences, known as Zeitgebers (Aschoff, 1954; Wever, 1979; Minors and Waterhouse, 1981a; Moore-Ede et al., 1982).


Circadian Rhythm Experimental Phase Control Phase Internal Oscillator Isolation Unit 
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Copyright information

© Springer Science+Business Media New York 1992

Authors and Affiliations

  • D. S. Minors
  • J. M. Waterhouse

There are no affiliations available

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