Modelling Sleep Propensity and Sleep Disturbances

  • Hartmut Schulz
  • Erik Bes
  • Marc Jobert


Sleep propensity (SP) can be defined as the readiness to transit from wakefulness to sleep, or the ability to stay asleep if already sleeping. The time course of SP within 24 hours shows several distinct features. The predominant temporal distribution of human sleep is characterized by the occurrence of one long sleep episode within each circadian cycle. This pattern is typical for entrained and free-running conditions (Czeisler et al., 1980; Zulley et al., 1981). It has been shown that the strength of the monophasic sleep—wake distribution depends on the strictness of the sleep—wake schedule and that additional, shorter sleep episodes appear with a greater chance if the experimental or social restrictions to fall asleep are low (Campbell, 1984). The most frequently observed deviation from a monophasic sleep—wake distribution is the occurrence of an additional sleep episode in the afternoon, halfway between two episodes of night sleep (Soldatos et al., 1983; Campbell, 1984; Lack and Lushington, 1996). Although napping is the most obvious indicator for systematic fluctuations of vigilance during daytime hours, additional evidence comes from circadian studies with performance tests (Minors and Waterhouse, 1981, chapter 6), and from the analysis of the temporal distribution of traffic accidents during 24 hours (Prokop und Prokop, 1955; Lauber and Kayten, 1988).


Sleep Onset Slow Wave Activity Multiple Sleep Latency Test Night Sleep Sleep Episode 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Achermann, P. and Borbély, A.A., 1994, Simulation of daytime vigilance by the additive interaction of a homeostatic and a circadian process. Biol. Cybern., 71: 115–121.PubMedCrossRefGoogle Scholar
  2. Åkerstedt, T. and Folkard, S., 1990, A model of human sleepiness, in: Sleep’ 90 (J.A. Horne, ed.), pp. 310–313. Pontenagel Press, Bochum.Google Scholar
  3. Bes, F.W., Jobert, M., Müller, C., and Schulz, H., 1996, The diurnal distribution of sleep propensity: experimental data about the interaction of the propensities for slow-wave sleep and REM sleep. J. Sleep Res., 5: 90–98.PubMedCrossRefGoogle Scholar
  4. Bonnet, M.H., 1985, Effect of sleep disruption on sleep, performance and mood. Sleep, 8: 11–19.PubMedGoogle Scholar
  5. Borbély, A.A., 1982, A two process model of sleep regulation. Human Neurobiol., 1: 195–204.Google Scholar
  6. Borbély, A.A. and Achermann, P., 1992, Concepts and models of sleep regulation: An overview. J. Sleep Res., 1: 63–79.PubMedCrossRefGoogle Scholar
  7. Borbély, A.A. and Wirz-Justice, A., 1982, Sleep, sleep deprivation and depression: A hypothesis derived from a model of sleep regulation. Hum. Neurobiol., 1: 205–210.PubMedGoogle Scholar
  8. Broughton, R., 1975, Biorhythmic variations in consciousness and psychological functions. Can. J. Psychol., 16: 217–239.CrossRefGoogle Scholar
  9. Broughton, R.J., 1985, Three central issues concerning ultradian rhythms, in: Ultradian Rhythms in Physiology and Behavior. (Experimental Brain Research, Supplementum 12, H. Schulz and P. Lavie, eds.), pp. 217–233, Springer Verlag, Berlin, Heidelberg, New York, Tokyo.CrossRefGoogle Scholar
  10. Brunet, D., Nish, D., MacLean, A.W., Coulter, M., and Knowles, J.B., 1988, The time course of ‘process S’: Comparison of visually scored slow wave sleep and power spectral analysis. Electroencephal. Clin. Neurophvsiol., 70:278–280.CrossRefGoogle Scholar
  11. Campbell, S.S., 1984, Duration and placement of sleep in a „disentrained“ environment. Psychophysiology, 21: 106–113.PubMedCrossRefGoogle Scholar
  12. Carskadon, M.A. and Dement, W.C., 1975, Sleep studies on a 90 minute day. Electroencephal. Clin. Neurophysiol., 39: 145–155.CrossRefGoogle Scholar
  13. Colquhoun, W.P., 1971, Biological Rhythms and Human Performance, Academic Press, London.Google Scholar
  14. Czeisler, C., Zimmermann, J., Ronda, J., Moore-Ede, M.C., and Weitzmann, E., 1980, Timing of REM sleep is coupled to the circadian rhythm of body temperature in man. Sleep, 2: 329–346.PubMedGoogle Scholar
  15. Daan, S., Beersma, D., and Borbély, A., 1984, Timing of human sleep: Recovery process gated by a circadian pacemaker. Am. J. Physiol., 246: R161–R178.PubMedGoogle Scholar
  16. Diagnostic Classification Steering Committee; Thorpy, M.J., Chairman, 1990, International Classification of Sleep Disorders, American Sleep Disorders Association.Google Scholar
  17. Dijk, D.J., Beersma, D.G.M., and Daan S., 1987, EEG power density during nap sleep: Reflection of an hourglass measuring the duration of prior wakefulness. J. Biol. Rhythms, 2: 207–219.PubMedCrossRefGoogle Scholar
  18. Dijk, D.J. and Czeisler, C.A., 1994, Paradoxical timing of the circadian rhythm of sleep propensity serves to consolidate sleep and wakefulness in humans. Neurosci. Lett., 166: 63–68.PubMedCrossRefGoogle Scholar
  19. Dijk, D.J. and Czeisler, C.A., 1995, Contribution of the circadian pacemaker and the sleep homeostat to sleep propensity, sleep structure, electroencephalographic slow waves, and sleep spindle activity in humans. J. Neurosci., 15: 3526–3538.PubMedGoogle Scholar
  20. Gaillard, J.-M., 1976, Is insomnia a disease of slow-wave sleep? European Neurology, 14: 473–484.PubMedCrossRefGoogle Scholar
  21. Hume, K.I. and Mills, J.N., 1977, Rhythms of REM and Slow-Wave sleep in subjects living on abnormal time schedules. Waking and Sleeping, 1: 291–296.Google Scholar
  22. Kobayashi, T., Tsuji, Y, and Endo, S., 1985, Sleep cycles as a basic unit of sleep, in: Ultradian Rhythms in Physiology and Behavior. (Experimental Brain Research, Supplementum 12, H. Schulz and P. Lavie, eds.), pp. 260–269, Springer Verlag, Berlin, Heidelberg, New York, Tokyo.CrossRefGoogle Scholar
  23. Kronauer R.E., Czeisler, C.A., Pilato, S.F., Moore-Ede, M.C., and Weitzmann, E.D., 1982, Mathematical model of the human circadian system with two interacting oscillators. Am. J. Physiol., 242: R3–R17.PubMedGoogle Scholar
  24. Lack, L.C. and Lushington, K., 1996, The rhythms of human sleep propensity and core body temperature. J. Sleep Res., 5: 1–11.PubMedCrossRefGoogle Scholar
  25. Lauber J.K. and Kayten, P.J., 1988, Sleepiness, circadian dysrhythmia, and fatigue in transportation system accidents. Sleep, 11:503–512.PubMedGoogle Scholar
  26. Lavie, P., 1985, Ultradian rhythms: Gates of sleep and wakefulness, pp. 148–164 in: Ultradian Rhythms in Physiology and Behavior (H. Schulz and P. Lavie, eds.) Springer Verlag, Berlin.CrossRefGoogle Scholar
  27. Lavie, P., 1986, Ultrashort sleep-waking schedule. III. Gates and „forbidden zones“ for sleep. Electroencephal. Clin. Neurophysiol., 63: 414–425.CrossRefGoogle Scholar
  28. Lavie, P. and Segal, S., 1989, Twenty-four hour structure of sleepiness in morning and evening persons investigated by the ultrashort sleep-wake cycle. Sleep, 12:522–528.PubMedGoogle Scholar
  29. Merica, H. and Gaillard, J.-M., 1991, A study of the interrupted REM episode. Physiol. Behav., 50: 1153–1159.PubMedCrossRefGoogle Scholar
  30. Minors, D.S. and Waterhouse, J.M., 1991, Circadian Rhythms and the Human. Wright PSG, Bristol, 1981.Google Scholar
  31. Prokop, O. und Prokop, L., 1955, Ermüding und Einschlafen am Steuer. Dtsch. Z. gerichtl. Med., 44: 343–355.Google Scholar
  32. Richardson, G.S., Carskadon, M.A., Orav, E.J., and Dement, W.C., 1982, Circadian variation of sleep tendency in elderly and young adult subjects. Sleep, 5: S82–S94.PubMedGoogle Scholar
  33. Roth, T., Roehrs, T., Carskadon, M., and Dement, W., 1989, Daytime sleepiness and alertness, pp. 14–23 in: Principles and Practice of Sleep Medicine. (M.H. Kryger, T. Roth, and W.C. Dement, eds.) W.B. Saunders, Philadelphia.Google Scholar
  34. Schulz, H., 1987, REM latency after deliberate sleep interruptions. Sleep Res., 16: 223.Google Scholar
  35. Schulz, H., 1988, Some properties of the ultradian REM-nonREM sleep cycle and its interaction with circadian rhythms, pp. 171-185 in: Neurobiology of Sleep—Wakefulness Cycle. Metsniereba (T. Oniani, ed.), Tbilisi.Google Scholar
  36. Schulz, H., Bes, F.W., and Jobert, M., 1995, Modelling sleep propensity, Sleep Res., 24A: 6.Google Scholar
  37. Soldatos, C.R., Madianos, M.G., and Vlachonikolis, I.G., 1983, Early afternoon napping: A fading Greek habit, pp. 202–205 in: Sleep 1982, 6th Eur. Congr. Sleep Res. (W.P. Koella, ed.), Karger, Basel.Google Scholar
  38. Stahl, M.L., Orr, W.C., and Bollinger, C., 1983, Postprandial sleepiness: Objective documentation via polysomnography. Sleep, 6: 29–35.PubMedGoogle Scholar
  39. Strogatz, S.H., 1986, The Mathematical Structure of the Human Sleep-Wake Cycle. Lecture notes in mathematics, No. 69. Springer Verlag, Berlin.CrossRefGoogle Scholar
  40. Webb, W.B., 1988, An objective behavioral model of sleep. Sleep, 11: 488–496.PubMedGoogle Scholar
  41. Webb, W.B., 1994, Prediction of sleep onset, pp. 53–72 in: Sleep Onset. Normal and Abnormal Processes (R.D. Ogilvie and J.R. Harsh, eds.). American Psychological Association, Washington, DC.CrossRefGoogle Scholar
  42. Webb, W.B. and Agnew, H., 1975, Sleep efficiency for sleep-wake cycles of varied length. Psychophysiology, 12: 637–641.PubMedCrossRefGoogle Scholar
  43. Weitzman, E.D., Nogeire, C., Perlow, M, Fukushima, D., Sassin, J., McGregor, P., Gallagher, T., and Hellman, L., 1974, Effects of a prolonged 3-hour sleep—wakefulness cycle on sleep stages, plasma cortisol, growth hormone and body temperature in man. J. Clin. Endocrin. Metab., 38: 1018–1030.CrossRefGoogle Scholar
  44. Wever, R.A., 1984, Toward a mathematical model of circadian rhythmicity, pp. 17–79 in: Mathematical Models of the Circadian Sleep-Wake Cycle. (M.C. Moore-Ede and C.A. Czeisler, eds.) Raven Press, New York.Google Scholar
  45. Zulley, J., Wever, A., and Aschoff, J., 1981, The dependence of onset and duration of sleep on the circadian rhythm of rectal temperature. Pflügers Arch. 391: 314–318.PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • Hartmut Schulz
    • 1
  • Erik Bes
    • 2
  • Marc Jobert
    • 3
  1. 1.Department of NeurologyKlinikum Erfurt GmbHErfurtGermany
  2. 2.Department of PsychiatryUniversity Clinic Benjamin FranklinBerlinGermany
  3. 3.PAREXEL GmbHBerlinGermany

Personalised recommendations