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The biological activity of the catholyte and anolyte of bidistilled water in experiments with the germination of wheat grains in the period from March to May has been studied. The activity of solutions, which was characterized by the grain germination index, was high at the beginning of the period, then it gradually decreased and was equal to zero at the middle of the period; at the end of the period it gradually increased almost to initial values. It has been established that the effectiveness of bidistilled water anolyte was as a rule higher than that of catholyte throughout the observation period. At the beginning and end, the stimulating effect of anolyte was 5-5.5 times greater than that of catholyte. The seasonal changes in the biological activity of M 9 medium catholyte were compared with those of bidistilled water anolyte and catholyte. The stimulating effect of M 9 catholyte was estimated by changes in the growth of E. coli cells. The stimulating effect, which was estimated from an increase in the optical density of cell suspension in the initial period at a cultivation temperature of 20 degrees C was 55-60% relative to control (untreated medium). Then it decreased almost to zero in the middle of the period to increase again approximately to the initial values. The assumption has been made that the physicochemical causes of the influence of catholyte and anolyte of bidistilled water on wheat grains and of the culture medium catholyte on E. coli cells are of different nature.

The fact of modulating influence of low-intensity electromagnetic field on the behavioral acts in mice was established. The dependence of mice behavior on the modulating frequency, electromagnetic field parameters (intermittent or continuous) and on the time of adaplive reaction was found.

The modifying influence of the weak electromagnetic field on the development of the audiogenic spasmodic activity in rats was shown. The decrease of lifetime of experimental rats exposed to electromagnetic fields with different parameters and development of tumours (in one set of experiments) was found.

It was shown that the electromagnetic field of low intensity modifies the evoked epileptiform seizure activity in rats. Cumulative effect of the electromagnetic field persisted over the course of 6 months. It was suggested that inhibition of the increased motor activity under exposure to electromagnetic field is caused by the involvement of dopaminergic brain systems and development of the resonance effects in cortico-subcortical brain structures under the influence of modulated electromagnetic fields.

Effects of CMF on memory processes in adult volunteers (non-sleep us hypnotic condition) has been studied at laboratory and clinical conditions. The results point out that CMF changes the interhemispheric relations and result in memory malfunction. The malfunction of memory activity in volunteers after action of CMF was influenced by two factors: magnetic field position under different brain areas and functional status of volunteers: awake or hypnotic.

Electrical asymmetry of electrograms of the rat symmetrical brain areas was decreased under the UHF irradiation of the animals. Non-modulated UHF field increased the 1.5 and 6 Hz rhythms in the left hemisphere, whereas modulated UHF field decreased the 1 Hz rhythm in the right hemisphere. The effects were only occurring at the initial period of the UHF fields use.

In order to study resonance phenomena in the EEG response to flickering light, 10 subjects were exposed to intermittent photic stimulation with the frequency of flashes linearly changing from 1 to 15 Hz and vice versa. Spectral analysis of occipital electrical activity revealed the occurrence of peaks of spectral density in those frequency components which coincide with the frequency of flashes. Such resonance peaks were observed at individually specific frequencies of stimulation. To assess the stability of the characteristics of the resonance phenomena, a repeated trial with 4-fold higher rate of changing the flash frequency was performed 3 months later. In a repeated trial the resonance phenomena were less pronounced, but were registered at the same frequencies as in the initial trial, showing significant test-retest reliability. The data obtained are interpreted in terms of provoking the activity of multiple brain oscillators having a narrow tuning to individually specific frequencies of photic stimulation by flickering light with the changing frequency of flashes.

A study was made of the influence of SHF radiation (8 mW/cm2, carrier frequency 0.88 Hz, modulation frequency 16 Hz) on rotation of rats induced by apomorphine. A single exposure within an hour was shown to inhibit apomorphine-induced rotation by 21%. Daily one-hour exposure within 5 days caused a more pronounced inhibition of test-response. Different individual sensitivity to SHF radiation was noted.

The influence of lateralized and bilateral electrical stimulations of the rat's brain on the course of audiogenic convulsive fit was analyzed. It was found, that after operative application of electrodes to the animal's skull the strength of fit and audiogenic seizure susceptibility decreased in all experimental groups. At the same time the second group, in which the left hemisphere was stimulated, essentially differed from other groups. The occasions of omission of some stages of fit were not so frequent, there, and only in this group after electrostimulation fits increased in the form of arising of new stages. This allows us to propose a special role of the left hemisphere of rats in forming a complete convulsive fit. The described observations resemble those of human asymmetry.

SHF radiation of low intensity does not influence on a stereotyped behaviour of rabbits induced by a dopamine receptor stimulator, apomorphine. However, 10% of animals exhibited a marked decrease in the test-response after SHF-irradiation (16 Hz) which was perhaps associated with the increased individual sensitivity of some animals to SHF-radiation.

We investigated the electrical activity of the occipital, sensorimotor, and frontal zones in the right and left hemispheres of the cerebral cortex and times for bimanual motor response in healthy adult experimental subjects between the ages of 15 and 25 receiving photostimulation by means of pulse trains with frequencies increasing from 15 to 25 Hz and pulse trains with frequencies decreasing from 15 to 5 Hz. We observed nonspecific physiological reactions in the organism regardless of the type of photostimulation presented and also observed specific reactions dictated by the parameters of the light stimulus acting upon the brain. It was demonstrated that the action of the light was most effective when the frequency of the stimuli was gradually increased. The expressiveness of the alpha-band of oscillations in the electrical brain activity increased in this case, and the asymmetry of the bimanual motor responses changed significantly. A definite connection was noted between the physiological reactions of the experimental subjects and their subjective states.

In experiments on 48 human subjects aged from 16 to 25 years, elaboration of present reactions to a complex stimulus was accompanied by stabilization of SGR not only in response to the first, triggering, and the last, reinforcing, components of the complex stimulus, but also to its central element provided it was a proprioceptive signal. In addition, SGR magnitude at the moment of the stimuli action was more considerable during the formation of trace processes as compared with one observed during elaboration of present reactions. The results obtained lead to the assumption that reproduction of excitation traces is preceded by the brain estimation of the time equal to the interstimuli pause.

The dynamics of formation, reproduction, and recognition of trace conditioned reflexes to positive and differentiation stimuli was studied on subjects of 15-17 years old. Formation and reproduction of such reflexes was found to occur under a close interaction of both levels of the higher nervous activity--recognized and unrecognized levels. Recognized reactions prevailed on unrecognized ones in cases of involvement of active attention. On the basis of this fact, the formation and reproduction of trace conditioned reflexes to positive stimuli has been supposed to occur with an active participation of the left hemisphere. The right hemisphere apparently plays a leading role in formation and reproduction of trace conditioned reflexes to differention stimuli to which the attention of the subjects was not fixed.

Human electrical cerebral reactions to acoustic stimuli and to their omission at fixed moments of a restricted rhythmic sequence repeatedly presented in conditions of distraction and attraction of attention to stimuli, were recorded on the vertex. By special methods of bioelectrical signals processing on a computer, the potentials are singled out in response to stimulus omission (SO) with each set ordinal number, which, as well as the potentials, evoked by the actual stimulus (AS), possessed a main negative-positive complex N1P2. In conditions of attention distraction, the negative component of this complex had a latency of 144 ms and the positive one--about 207 ms. In the situation of the attraction of attention to stimuli a decrease of N1 latency up to 125 ms, took place, as well as complication of SO configuration due to the appearance of a later positive oscillation with a latency of about 560 ms, and parametres stabilization of SO as a whole. The analogous dynamics of N1 latency was characteristic of AS in both situations. The mechanisms of SO formation are discussed in connection with trace processes in the central nervous system.

In 43 female Wistar rats, a loud sound did not alter the asymmetry in behavioral tests even if is was loud enough to induce seizure. Under apomorphine test, the sound tended to decelerate the rotation, the asymmetry being preserved both in sound-activated and in sound-resistant subgroups. A shortening of the rotation onset latency occurred in sound-activated subgroup which may be associated with an increased permeability of the hemato-encephalic barrier following the sound-induced seizure.

The EEG of occipital areas was recorded in adult healthy male subjects on presentation of haphazardly alternating intermittent light stimuli with frequencies varying from 15 to 5 Hz and from 15 to 25 Hz every 5 sec. Two groups were distinguished in respect to a greater or lesser domineering of the main frequency band of the range. Dynamic spectral analysis revealed obvious shifts of the EEG spectral composition in respect to the background under the effect of the stimulation, an enhancement of different bands of the range in light flickering, and the suppression of the EEG trace responses to the time in the EEG range coinciding in frequency with the frequency range of the photostimulation. The above changes were mainly characteristic of the 2nd group of subjects and mostly of the left hemisphere of the brain.

Grown-up subjects revealed both unspecific and specific bimanual motor responses to photostimulation with growing and declining frequency. The former mode of stimulation proved more effective. A relation was found between the physiological responses of subjects and their subjective condition.