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This paper is a review of hypotheses of consciousness which arose from application of the theory of information and regulation and the cybernetic theory of mathematical machines in medicine. The author presents these hypotheses on the examples of his own works.

Circadian rhythm of TSH was analyzed in patients with cold tumors of the thyroid before and after surgical removal of the tumors and in control subjects. By using special computer program BIOR based on harmonic and regression analysis, designed for verifying and comparing various biorhythms, significant differences were found between TSH biorhythms in patients with cold thyroid tumors before and after the operation.

In a group of 52 patients with hearing and equilibrium disturbances of central origin EEG was done. The obtained EEG findings were correlated with: a) main clinical manifestations of the type of function loss or stimulation, and b) disturbances of behavioural perception, that is specific signs of disturbed perception and non-specific extraperceptive signs. Disturbed hearing, independently of the side of lesion, was accompanied by focal disturbances of electrogenesis in left temporal leads. Vertigo was associated as a rule with focal pathological changes in parieto-occipital leads bilaterally, prevailing in the right-side leads. The pattern of labyrinthine (static) behavioural disturbances was, as a rule, more rich than that of hearing behaviour disturbances. The differences observed in clinical pattern were explained as due to differences in the neurophysiological properties of the temporal and parieto-occipital cortex. Conclusions were based on the hypothesis of minimal brain damage and dipolar organization of the pathological bioelectric function of the brain. Electroencephalography provides objective data which can be used in the diagnosis of diseases affecting the organs of hearing and equilibrium.

Synaptic weights, axonal delays and excitability thresholds are three basic parameters influencing the function of neuronal network as a dynamic system. Changes of the general level of the signal flow, without changes in relation between excitatory and inhibitory connections can cause pathologic oscillations in the network. The conductivity in neuronal nets depends on electrochemical processes and may be influenced by the pH-status, ion concentrations, among other parameters. Also different pathological processes can change it. Even slight changes of axonal delays, as shown above, can cause in certain situations unstable, epileptic oscillations of the net.

The occurrence of synchronous, self-sustaining seizure activity is one of the basic mechanisms underlying epileptic attacks. Using a mathematical model of neuronal network in various simulation experiments carried out in digital computer the conditions were studied of the development of pathological epileptic activity and the conditions of the parameters of this network affecting its stable function. After exceeding of a threshold value in the relation between the weights of the stimulating and inhibiting synapses an unstable epileptic response appears. In the state of the so called conditional stability the network is highly sensitive to even small changes of the parameters. These observations make possible a new look at a number of phenomena found in clinical cases and in experiments.