[The Features of Saccadic Reactions to a Consequent of Visual Stimuli in Healthy Subjects and Patients with Schizophrenia].

We studied the features of cognitive functions of attention and decision making in 18 healthy subjects and 15 patients with schizophrenia with the use of pairs of two short visual stimuli (double step). In the group of patients with schizophrenia, we observed a higher number of errors and higher frequency of modified saccadic pattern--two saccades to each stimulus instead of only one saccade to the second stimulus. In these patients, the latency period of the first saccade was shorter, while the latency period of a single saccade to the second stimulus was longer as compared with healthy subjects. The lateral differences in the saccade latency in schizophrenic and healthy subjects are opposite. The data provide an evidence of disorders in the cognitive control and prognostic processes of saccade programming in schizophrenic patients.

[The changes of EEG correlation synchrony at depressive disorder of psychogenic type].

In this work we use the alternative method of assessing the EEG-synchrony which previously has proved its high sensitivity to the differentiation of psychopathological and functional states. The original recording of EEG had been performed in the state of quiet wakefulness with eyes closed for two groups of examinees/patients at the age of 49-82 years: a group of normal subjects (n = 29) and the group of subjects with depressive deviations of F43.21 category according to ICD-10 (n = 51). As a result of research it is received the comprehensive picture of significant topographical, interhemispheric and regional differences between groups of norm and depression. One of basic features of the obtained integrated picture is existence at a depression of the extended zones of reduced EEG-synchrony covering the entire premedial region in the frontal-occiptal direction, including intrahemispheric connections as well as lateral frontal-temporal connections in both hemispheres. It testifies to the deep deprivation with depression frontal-occipital and interhemispheric interaction. As a compensatory reaction during depression the increase of synchrony in axial aimed intrahemispheric pairs of derivations. It is noted the similarity of changes in EEG-synchrony topography of depression to those observed in schizophrenia. The used method has provided close to 100% reliability of the classification of the EEG norms and depressive deviations, which makes possible and promising its use as an auxiliary quantitative differential indicator.

[Saccade latency and pattern of saccade response in the experimental scheme "double step"].

To investigate the decision-making process at the saccade programming we used modification of the "double step" experimental scheme, in which two short stimuli are presented successively in the opposite semifields (puls overshoot--scheme). The dependence of saccades to visual stimuli number, responses pattern (two saccades, or a single saccade to the second stimulus) and the value of saccade latency from the first stimulus duration (150 or 50 ms), the spatial stimuli arrangement and the individual characteristics of the subjects was shown. The findings suggest the relationship of attention and decision making processes at saccade programming and indicate to the possible influence of prognostic processes on the saccadic response "pattern" at the expectation period in the experimental "double step" scheme.

[Comparative analysis of EEG correlation synchronism and EEG amplitude relationships in all-night sleep].

We used a new methodological approach to the evaluation of EEG synchronization based on correlation between amplitude modulation processes (EEG envelopes). We revealed: left-hemispheric dominance and dominance of frontal over occipital regions characteristic of all sleep stages; differences in synchronization in frequency bands and their patterns characteristic of a specific sleep stage; stage-dependent differences in inter-hemispheric synchrony and patterns of their changes from the frontal to occipital regions; and stage-dependent topographical distributions of high synchronization foci with respect to frequency domains. Analysis of amplitude topography also revealed left-hemispheric dominance and many significant differences in activity distribution patterns over parasagittal chains of electrodes (meridians) depending on sleep stages and frequency domains. The combination of EEG synchrony estimates with the amplitude spectral estimates made it possible to perform a reliable discriminant recognition of five sleep stages with errors in the range of 3-20%.

[The method of correlation analysis of EEG synchronism and its possibilities].

A new method for estimation of EEG synchronism based on the analysis of correlation between amplitude modulation processes (envelopes) is considered. The efficiency of the given method is shown in different aspects: for detection of a topographical pattern, for analysis in frequency domains, for estimation of stability of the functional state and its changes, for detection of heterogeneous subgroups of subjects and outliers, for analysis of individual and group distinctions and distinctions in synchronism between symmetrical pairs of leads and hemispheric asymmetry, and for classifying division between mentally healthy subjects and deviations of schizophrenic spectrum with reliability approaching 100%.

[On the informative value of coherence analysis in EEG studies].

Numerous methodological and computing errors characteristic of coherence analysis as applied to EEG studies are discussed. The comprehensive review of basic disadvantages of coherence function does not allow the author to consider it as a reliable and effective index of EEG synchronism.

Functional characteristics of the mature and developing brain following neuroimmunization: analysis of short-term plasticity in the rat hippocampus.

The influence of neuroimmunization by the total antigens of the cytosol fraction of hippocampal tissue or neocortical tissue on the indices of short-term plasticity in adult and developing (3 to 4 week old) Wistar rats has been investigated. Short-term plasticity was evaluated on the basis of changes in the slow-wave component of the focal potentials (FP) of the CA3 field of the hippocampus upon stimulation of the region of the dentate gyrus. The FP were recorded under nembutal anesthesia. In the groups of the hippocampus of adult and developing immunized rats, the greatest changes in short-term plasticity in the form of extreme intensification of the expressivity of the properties of paired facilitation and frequency potentiation were confined to the pyramidal layer. In the neocortex groups, the changes, as a rule, were less marked, and had the opposite sign; the main differences were found in the recording of the FP in the zone of the apical dendrites of the pyramidal neurons. It was noted that the focal activity of the young immunized animals is characterized by greater maturity as compared with the age norm. A conclusion is drawn regarding the different primary localization of the targets of the neuroimmune effect when antigens of different brain structures are used, namely hippocampus versus neocortex, and regarding the dependence of the physiological effect of neuroimmunization on the degree of maturity of the target structure.

[Functional characteristics of the mature and developing brain following neuroimmunization: an analysis of the short-term plasticity of the rat hypothalamus]. / Funktsional'nye kharakteristiki zrelogo i razvivaiushchegosia mozga posle neiroimmunizatsii: analiz kratvovremennoi plastichnosti v gippokampe krys.

In experiments on mature and developing (3-4 weeks old) rats the influence was shown of neuroimmunization with summate antigens of hippocampal or neocortical tissue cytosolic fraction on short-term plasticity of hippocampal CA3 field potentials under dentate gyrus zone stimulation. An increase of paired facilitation and frequency potentiation was revealed in pyramidal layer responses of hippocampal tissue immunized animals. In case of immunization with neocortical antigens the changes were less expressed, had mainly the opposite direction and took place in the apical dendrites zone. In young animals besides antigen spectrum depending effects of neuroimmunization an earlier manifestation (in comparison with age norm) of some focal activity definitive properties was described. The suggestions are made about different localization of hippocampal or neocortical tissue immunization "targets" with possible preferential damage of intrahippocampal systems when using this structure antigens, and also about dependence of physiological consequences on the extent of target structure ontogenetic maturity.

[Differences in the EEG synchrony between healthy children and adolescents and patients with schizophrenia].

In this paper, we have used a method for EEG synchrony estimation (an analysis of correlation synchrony of EEG. EEG recording was performed in a group of children and adolescents, aged 8-15 years, normal group (n=40) and schizophrenic group (n=30). One of the basic features of the integrated EEG picture is the presence of a pathology of extended zones of sharply lowered EEG-synchrony dividing the local and isolated areas in frontal and occipital regions, mainly of normal or sometimes raised synchrony. Also, there were significant correlations of synchrony estimates with memory and attention. The results obtained are in line with the theory of disintegration of cortical electrical activity in schizophrenia spectrum disorders. It is important that the used method provides the high reliability (up to 100%) of the differentiation between normalcy and a pathology.

[A multifunctional system for automating physiological experiments]. / Mnogofunktsional'naia sistema avtomatizatsii fiziologicheskogo ékseprimenta.

The methodical problems of automatization of physiological investigations on the basis of modern computer complexes "micro-CAMAC-lab" are discussed. The considered conceptions are illustrated by example of CAMEX-program-system ensuring the measurement, storing, visual control, editing and analysis of physiological experimental data.

[Automation of research on memory using computers]. / Avtomatizatsiia issledovanii pamiati s pomoshch'iu EVM.

The article discusses the direction of integrated automation in memory investigations on the basis of hardware-software conveyor consisting of three interacting polyfunctional systems. All the systems are characterized by flexibility, accessibility and efficiency for memory investigations on the behavioral, macro- and microphysiological levels.