Historical Perspective In 1842, in a paper entitled "Further Development of a General Law of Vital Periodicity", which was part of a series of seven Lancet papers on periodicities in health and disease, Thomas Laycock wrote: "As everything finite must have a period within which its existence is circumscribed, so every period so circumscribing the finite, being a measure of time, must be divisible into lesser periods. But it has always been found easier to reason from generals to particulars than to ascend from particulars to generals, especially in questions in volving the phenomena of life" (p. 423). From a historical perspec tive, Laycock's insight indeed anticipated the progress of chronobio logic research. In spite of the abundant evidence pointing at the existence of short-term rhythms with periodicities much shorter than 24 hours, termed "ultradian" rhythms after Halberg (1964), it has gen erally been found much easier to investigate circadian rather than uI tradian rhythms. In m~st cases, ultradian rhythms have been ignored, or dismissed as insignificant phenomena, even in cases where they could be easily "eyeballed" in the data. Laycock himself believed that the most basic periodicity in vital phenomena was 12 hours. Short-term fluctuations in the levels of certain behaviors, which could not be accounted for by external stimulation or by internal stimuli, have been known to ethologists and other observers of animal behavior for many years.
Reihe
Sprache
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Verlagsgruppe
Zielgruppe
Für höhere Schule und Studium
Für Beruf und Forschung
Illustrationen
biography, 90 figs., 20 tabs.
Gewicht
ISBN-13
978-3-540-15439-6 (9783540154396)
DOI
10.1007/978-3-642-70483-3
Schweitzer Klassifikation
Introductory Note.- Section 1 Ultradian Rhythms in Physiology and Endocrinology.- Ultradian Rhythms in Behavior: The Case of the Common Vole (Microtus Arvalis).- The Circhoral Gonadotropin Releasing Hormone (GnRH) Pulse Generator of the Hypothalamus and Its Physiological Significance.- Pulsatility of Pituitary Hormones.- Relationship Between Ultradian Rhythms of the Sleep-Wakefulness Cycle and Growth Hormone and Corticosterone Secretion in Rats.- Ultradian Rhythms in Locomotor Activity, Deep Body Temperature and Plasma Corticosterone Levels in Rats: Two Different Origins?.- Interaction Between Circadian and Ultradian Rhythms of Spontaneous Locomotor Activity in Rats During the Early Developmental Period.- Urinary Ultradian Rhythms in Dogs.- Timing Function of the Dorsal Raphe Nucleus and the Temporal Organization of the Ultradian Sleep Cycle.- Section 2 Sleep and Waking Rhythms.- Ultradian Rhythms: Gates of Sleep and Wakefulness.- Ultradian Rhythms in the Nychthemeron of Narcoleptic Patients and Normal Subjects.- The Basic Rest-Activity Cycle Revisited: Some New Perspectives.- Ultradian Rhythms During Sustained Performance.- Three Central Issues Concerning Ultradian Rhythms.- Ultradian Components of Human Sleep/Wake Patterns During Disentrainment.- Section 3 Methods and Models.- Sleep Cycles as a Basic Unit of Sleep.- In Search of REM Cycle in Short Sleep Record: Iterative Nonorthogonal r2 Method.- The REM Sleep Ultradian Rhythm: A Limit Cycle Mathematical Model.- Modes of Interaction Between Ultradian and Circadian Rhythms: Toward a Mathematical Model of Sleep.- Epilogue.- On Diversity and Uniformity of Ultradian Rhythms.
