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This paper analyzes the variation of the functional anatomy of the brain in healthy people performing identical activities on the basis of functional magneticresonance imaging (fMRI). According to the authors, this approach allows you to showcase a variety of individual strategies to achieve the same external (behavioral) result intracerebral different means, and to identify the factors that determine this diversity. Investigated hemodynamic (fMRT) brain reactions at activization of attention to opening of eyes, motor (search of the right and left hand fingers) and speech tests (mental transfer of months or days of the week upside-down) at 21 healthy subjects (21-30 years): 14 men, 7 women. Certain variety of fMRT answers is revealed: 3-4 jet types of hemodynamic changes were allocated for test in group, and the percent of supervision of each type fluctuated from 40 to 10%. Shown marked gender differences responses which specificity is determined by the nature of the functional load. In motor and speech tests, performed with his eyes closed, fMRI response in women is characterized by greater specificity and locality than in men. At motor tests fMRT answers of men are accompanied big, than at women, inclusion in reaction of frontal areas of the cortex, providing realization of regulatory functions. When opening of eyes the women's fMRT responses, on the contrary, become more diffusion, and men's--more local.

Bioelectrical (EEG) and hemodynamic (fMRI) responses of cerebral reactions to active and passive movements by the right hand were analyzed in 17 right-handed healthy persons. Individual and averaged fMRI and EEG data was analyzed. The main cortex fMRI responses (sensorimotor cortex of the contralateral, left hemisphere) were topographically similar during both active and passive movements. This fact allows us to recommend the usage of the passive movement paradigm for the mapping of the motor areas in patients with movement disorders. Including in reactive process of cerebellum and subcortical structures at passive movements was more variability than active ones. FMRI-reactions at passive movements were characterized more individual variability than during active ones at the expense of diversity of cerebellum and subcortical structures answers. The EEG analysis revealed that at both passive and active movements there is a coherence increase in the high-frequency alpha-ban in left central-frontal area of the left, activated hemisphere. The power-frequency changes of the EEG parameters during active and passive movements were primarily shown in a frequency increase and the desynchronization of the beta-band. Consistency with the topography of the fMRI response was not found.

Bioelectrical (EEG) and hemodynamic (fMRI-response) cerebral reactions to performance and imaginary motor tasks by right or left hand were analyzed in 15 right-handed healthy persons (21-39 years old). During actual movement the main fMRI-response was registered in the area of central gyrus of the hemisphere contralateral to the working hand. Areas of activation were also revealed in the supplemental motor area and the ipsilateral hemisphere of the cerebellum. EEG data showed coherence increase in high frequency alpha- and beta-bands in the activated hemisphere. In imaginary motor tasks the intensity and topography of fMRI-response became the more variable; response was decreased in the motor area and in cerebellum, they increased in the subcortical structures and in the parietal association zones. EEG changes were very variable in this situation also; it was observe an increase of EEG coherence in the right hemisphere for higher frequency of alpha and beta spectral bands. Changes of power spectrum parameters were similar to performance and imaginary motor tasks. Spectrum power and middle frequency of beta band were increased. Topographically these changes did not correspond to activated hemisphere and it was more in the left hemisphere. These changes were reflected nonspecific component of reaction.

To gain a deeper insight into the relationship between the electrogenesis and oxygenation of the brain, fMRI and EEG reactions to identical functional loads (opening of the eyes and right- and left-hand fingering) were compared in 11 young right-handed healthy subjects with statistical techniques. Changes in power, frequency and coherent EEG parameters obtained by 18-channel monopolar recording were compared with values of + BOLD-fMRI response, calculated for 18 corresponding cortical areas on the basis of application of the "virtual cap" by the original algorithm. In reactive changes of both hemodynamic and bioelectrical parameters, sets of independent factors were identified, which were regarded on the basis of their topography as specific (localized in the cortical representation ofa relevant analyzer) and nonspecific (diffuse and similar under different functional loads). Specific component dominated in the fMRI response, whereas non-specific component was characteristic of the EEG reaction. The similar topography of reactive fMRI and EEG factors under normal conditions, confirmed by the correlation analysis, reflects the multilevel character of the systemic organization of the brain activity, visualized, in particular, in the sagittal projections of the individual fMRI images. Each of the reactive EEG factors included all of the EEG quantitative characteristics. EEG coherence, which dominated among other parameters (with a local increase in the cortical representation of a relevant analyzer and a diffuse decrease in the areas of the influence of the regulatory structures) displayed the highest correlation with hemodynamic responses of the brain.

21 patients with lumbosacral osteochondritis and diskal hernia were treated. Diagnosis was verified with the help of radiological method. The spinal motion segment after the hernia excision was fixed with the help of fixator with the shape memory for the prevention of post-operation instability. Thioctic acid showed the high effectiveness in complex treatment of radiculopathy.

fMRI (1.5 or 3 T) and EEG studies with estimation of reactive responses on motor task (by right or left hand) were performed in 9 patients with tumors localized in frontal lobe of the brain. Results of this investigation were compared with results of the similar study in 12 healthy persons. It was shown that in cases of the brain pathology disorders of functional specialization and increase of diffuse component of reactivity was observed, fMRI-responses had been characterized the more intact reactions than reactive changes of EEG parameters. This specificity was described in cases of afferent loads in damaged hemisphere. Peculiarity of including different spectral bands in forming of EEG responses on motor tasks and changes of fMRI-answer depend on degree of cerebral decompensation, reflected in the of baseline EEG reorganization and degree of motor defect. Predominantly an increase of EEG coherence in delta-band with the predominance of reaction in the damaged hemisphere in cases of addressing any afferent load was observed in patients with severe cerebral decompensation and reflect dominant character of pathological focus forming. This data indicate on the more including of the deep brain structures in process of reactivity in patients compared with healthy persons and confirmed by fMRI-data.

In order to study systemic brain reactions on transcranial electrical or electromagnetic medical stimulation and specify the neurophysiological criteria of its efficiency, comparative clinical and experimental examination was performed with the analysis of spontaneous bioelectric activity and behavioral or clinical parameters. We examined 6 patients with prolonged posttraumatic unconsciousness states treated with electrical stimulation and 17 intact Wistar rats subjected to electromagnetic stimulation of the brain. The effect of the transcranial stimulation was shown to depend on the initial level of the intercentral interactions of brain bioelectrical activity, estimated by the EEG coherence. Hypersynchronization of biopotentials as the main element of the brain reactivity can be the most useful for the rehabilitation of patients with cerebral pathology in cases of initially lowered level of the intercentral interactions in the absence of pathologically strengthened functional connections.

Thirty two patients, 21 with recurrent and 11 with chronic Korsakoff's syndrome of traumatic genesis, and 20 healthy subjects were studied, using visual and spectral coherent EEG analysis and investigation of three-dimensional localization of dipolar beta 1-activity sources (13-20 Hz EEG bands). In Korsakoff's syndrome, negative prognostic significance of a stable increase of EEG beta 1-activity coherence generated by a limited number of sources, preferably of frontal basal and stem localization, was found. In the context of clinical data, this EEG phenomenon may be related to inhibited state of corresponding cortical areas.

The concern of the work was in detection and analysis of P300 component of the acoustic evoked potential in healthy subjects in different experimental situations. During counting the rare sounds, P300 was most pronounced in the frontocentral and parietooccipital areas mainly of the left-hemisphere. The response shape was correlated with characteristics of the basic rhythm of the background EEG. Responses of simple and complex shapes were distinguished. The simplest responses were recorded in subjects with hypersynchronous alpha-rhythm. Analysis of three-dimensional dipole source localization showed that structures of the brainstem, limbic system, and frontal lobes participate in generation of the wave. In all the subjects, the decisive role in response generation was played by the brainstem structures. In persons with hypersynchronous alpha-rhythm, the contribution of the frontal lobes was less pronounced. During "passive" listening of sounds, P300 parameters significantly differed from those observed during counting only in 46% of cases (in persons having no hypersynchronous alpha-rhythm). A simplification of the response shape during "passive" listening was observed in these cases, the area of the maximal response expression was shifted to symmetrical areas of the right-hemisphere, the number of dipole sources reduced due to a decrease in the contribution of the frontal and limbic structures into the response generation.

The authors specify and describe 7 stages of regaining consciousness by patients who had been in coma from 11 to 180 days, including opening of the eyes; fixation of the eyes on an object; recognition of close relatives; understanding of directly addressed speech; patient's own speech; amnestic confusion; consciousness with all formal signs of being clear. The condition of the patients at these stages is compared with EEG findings suggestive of the functional disintegration of the brain as a system in comatose patients, the vegetative status and the restoration of connections between different departments of the brain corresponding to the recovery of long absent consciousness of patients. It is concluded that at the current stage of medical sciences the maximum duration of coma compatible with the subsequent full recovery of mental activity of the patient under 30 years does not exceed 11 days.