[The dependence of the discharge frequency of muscle spindle afferents in the cat on the direction of the change in muscle loading].

Hysteretic effects in activity of the muscle spindle endings were studied using slow reciprocating changes in the external load. It was shown that the hysteretic loops of the frequency-muscle length were always broader than those of the frequency-muscle force. A conclusion has been made than the spindle tension tracking was better than the length one with respect to the corresponding static errors.

[Dependence of the character of EPSP summation in mollusk neurons on the level of the membrane potential].

The dependence of monosynaptic EPSP summation properties on the membrane potential level was studied in the experiments on identified neurons of mollusc Planorbis corneus. Summation functions were obtained by means of randomized paired stimuli technique. It was shown that the value of the interstimulus++ interval corresponding to the most marked EPSP interactions depended, mainly, on the postsynaptic mechanism.

[Nonlinear temporal summation of EPSP in mollusk neurons].

Temporal summation of monosynaptic EPSPs produced by paired afferent stimuli was studied in the experiments on identified neurons of mollusc Planorbis corneus. Nonlinear properties of the summation were shown; there were three types of the summation: facilitation, depression and mixed type. It was shown that summation functions (characterizing the dependence of the ratio between the test and conditioning EPSP amplitudes and the value of the corresponding interstimulus++ interval) had some local extremum in most cases.

[Histological types of lung cancer and environmental factors].

The incidence rates of different histologic patterns of lung cancer for 1950-1970 and 1981-1985 were compared at 15-30 year-intervals. The relationship between smoking, occupational hazards and distribution of histologic patterns of lung cancer was studied, too. The study failed to establish any correlation between histologic pattern of lung cancer and said factors.

[Determination of the topical organization of the discharges of identified mollusk neurons].

Identified RPa1, RPa2 neurons of the right parietal ganglion of Planorbis corneus were investigated. Coherent analysis of accumulated electrical activity in periferal nerves and spike discharges in identified neurons was done. Using this analysis, the presence of axon processes of RPa1 and RPa2 cells in the left and right pallial nerves was determined.

[Wiener analysis of transmission of signals of identified mollusk neurons].

Mathematical model of spike train transmission by identified neurons of the mollusc Planorbis corneus was obtained by means of Wiener analysis. Poisson distributed sequences of near-threshold stimuli were used as input trains for construction and testing. It was shown that addition of terms sensitive to the nonlinear properties of the synapse-neuron system to the model decreased the model error from 25% to 16%.

[Deterministic and stochastic identification of neurophysiologic systems].

The paper deals with deterministic and stochastic identification methods applied to the concrete neurophysiological systems. The deterministic identification was carried out for the system: efferent fibres-muscle. The obtained transition characteristics demonstrated dynamic nonlinearity of the system.