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PubMedDate not supplied

[The interaction of circahoral and circadian rhythms. A cybernetic model].

Parameters of ideal circadian cycle were compared with those of a circadian cycle composed of near-hour fluctuations. The integral cycle was optimized by the algorithm of matrix random search studying the approximation of its parameters to the ideal cycle after the phase shift of the latter. Computer calculations revealed a low efficiency of the search by fluctuation amplitude. The search by phase and frequency was effective in a narrow range of changes and needed time. The average level of fluctuations tuned up practically immediately: ideal and optimized curves coincided in all points. Examples of interactions between day, near-hour and shorter cycles are cited.

Algorithms↗
PubMed1989

Cybernetic model of psychophysiological pathways: I. Control functions.

Electrophysiological events carry information, but the signals are not specific for a given bit of information. Therefore, the nervous system is required to extract the information from a multitude of signals. The process of information recognition is achieved by a superization process, i.e., by means of transition from many lower-order signals to a superior-order signal. In this way, a gradual recognition of the respective signal's emitting sources is realized. The recognition is performed with the aid of certain logical circuits representing models of different sources written in the structure of the neuronal network. In this manner, the nervous system passes step by step from control by means of signals to control by means of information. The superior structures can thereby exert much more subtle control and supervise the inferior structures that work by signals. However, because this control cannot refine all the general information of the inferior structures, psychophysiological dysfunction may occur. The nature of the superization process from signals to information is examined in this paper.

Cybernetics↗
PubMed1989

Cybernetic model of psychophysiologic pathways: II. Consciousness of tension and kinesthesia.

This paper describes a series of experiments directed toward the following questions: a) do signals from musculotendinous receptors reach consciousness?, and b) does feed-forward information of muscular force and expected extent of voluntary movement exist? To answer these questions, data from voluntary compression of springs and strain-gauge have been analyzed in healthy young subjects. By successive elimination of information from other sources, it was possible to verify that receptors in muscles and tendons do signal movement magnitude and muscular tension to the cerebral cortex, and that this information does reach consciousness. There also exists a feed-forward mechanism signalling parameters of voluntary contraction. However, it is unclear whether peripheral, subcortical or intracortical loops are directly involved.

Biofeedback, Psychology↗
PubMed1989

Cybernetic model of psychophysiologic pathways: III. Clinical impairment of tension and kinesthesia.

It is unclear whether peripheral, subcortical or intracortical loops are directly involved between receptors in muscles and tendons and the cerebral cortex in signaling movement magnitude and muscular tension information. Previous experiments have indicated that this information does reach consciousness. Data from voluntary compression of springs and strain-gauge were analyzed in patients with unilateral focal lesions of the cerebral hemispheres. It was found that the perception of signals of muscular tension is abolished by lesions of the contralateral cortex near the central sulcus. It was concluded that the possibility exists of separate cortical projection areas for kinesthetic signals from muscles and from joints.

Brain Diseases↗
PubMed1988

On cybernetics.

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Attitude to Computers↗
PubMedDate not supplied

A trial of cybernetic explanation of the development and regression of benign child epilepsy.

Using as an example the verification of a hypothetic mechanism of the course of benign child epilepsy the authors demonstrate a method of simulation investigations of neuron-like networks. The structure and possibilities of a digital system for network modelling are discussed, including the properties of the neuron-like element used presently for the experiments. The results of the simulation investigations described in the second part of the paper confirm the hypothesis that an attack of benign child epilepsy is a result of transgressing of the stability border by a fragment of the neuronal network with development in it of a self-exciting activity of a neuronal group.

Child↗