The Time Structure of Adaptive Processes

Journal/Book: In: G. Hildebrandt u. H. Hensel (Eds): Biological Adaptation. Thieme-Verlag Stuttgart-New York 1982 pp. 24-39. 1982;

Abstract: Institut für Arbeitsphysiologie und Rehabilitationsforschung der Universität Marburg/Lahn Summary The different time requirements of the various adaptive processes have long been used as a principle of classification. Living processes however are characterized not only by their temporal duration but also by their periodic time structures. The range of period durations observed in the spontaneous rhythmical functions in man is as extensive as the range of time requirements for the various adaptive processes. Increasing duration involves increasing complexity of both the spontaneous rhythms and the adaptive processes. Like other autonomous reactions adaptive processes are periodically structured their period durations however are never identical to those of the spontaneous rhythms. The phase position of reactive and adaptive periods depends an the timing of the Stimulation and the amplitudes damp down with increasing adaptive compensation. Undisturbed spontaneous rhythmicity thus characterizes the state of complete adaptation. As illustrated by the circaseptan reactive periodicity the periodic time structure of the adaptive processes depends an an alternation between trophotropic and ergotropic phases in the autonomous System. During the trophotropic phases the tolerance-increasing processes are dominant whereas during the ergotropic phases the capacity-increasing processes are preferred for adaptive compensation. The periodic adaptive response is evoked by a sympathetic alarm reaction caused by an exceeding of the capacity limit. The raising of the capacity limit which allows the reactive periodicity to damp down is prepared for under the protection of the tolerance-increasing processes during the trophotropic phases of the periodicity. . . .

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