[In search of an effective algorithm for rhythmic transcranial magnetic stimulation in neurorehabilitation after severe traumatic brain injury]. / V poiskakh éffektivnogo algoritma ritmicheskoi transkranial'noi magnitnoi stimuliatsii v neiroreabilitatsii posle tiazheloi cherepno-mozgovoi travmy.

Rehabilitation of patients with severe traumatic brain injury (sTBI) is a topical medical and social issue because this pathology is one of the main causes of mortality and disability in the young working age population [1]. The most common sTBI consequences include motor and cognitive impairment as well as depression of consciousness [2, 3]. Despite significant progress in treatment of the consequences of severe traumatic brain injury, there are no treatment and rehabilitation standards for these patients, and the used rehabilitation measures are not always effective. These circumstances substantiate the need for the development of additional methods of neurotherapy. Over the past decade, transcranial electrical and magnetic stimulation (TMS) has been increasingly used as neuromodulatory treatment in clinical practice [4-12]. The accumulated experience has shown that transcranial neurostimulation methods require a more individualized approach in terms of both careful selection of patients and choice of exposure parameters. This review is based on an analysis of the most significant publications and recommendations recognized in the scientific community, as well as on reports of domestic and foreign authors presented at dedicated congresses in comparison with experience of our own research on transcranial stimulation. The paper discusses the main problems of using this method in medical practice of sTMI and their possible solutions.

[The cholinergic deficiency syndrome in patients with depressed consciousness after severe brain injury]. / Sindrom kholinergicheskoi nedostatochnosti pri dlitel'nom ugnetenii soznaniya posle tyazheloi cherepno-mozgovoi travmy.

AIM: To determine the clinical and electrophysiological (EEG) signs of cholinergic deficiency in the process of recovery of consciousness in patients with severe brain injury. MATERIAL AND METHODS: Thirty-seven people (24 men and 13 women, mean age 32±14 years) were studied. A comprehensive study included assessment of neurological status, mental activity, and EEG. RESULTS AND CONCLUSION: A set of neurological symptoms, including reduced muscle tone, autonomic disorders (dry mucous membranes and skin, tachycardia, hypotension, gastrointestinal tract), eye movement disorders, that were,in accordance with the literature, characteristicof the cholinergic deficiency syndrome was found. This syndrome was detected against the background of a comatose state, akinetic mutism and mutism with understanding of speech, disintegration of speech, disorientation and amnestic decline. EEG revealed stable over time (months) characteristic changes: slowing and asymmetric alpha activity, equivalent dipole sources of hippocampal and stem localization, persistent strengthening of intra-hemispheric coherent connections, especially on the left side. The regression of the cholinergic deficiency syndrome was accompanied by an increase of regularity, capacity and frequency of alpha-activity (from 7-8 to 9-10 Hz), prevalence of equivalent dipole sources in the hippocampus with their appearance in the occipital cortex, normalization of connections with right-brain coherence with the preservation of their pathologically high values on the left side.

[The Futures of Auditory Passive Perception While Listening to Sounds in Healthy Persons of Young or Advanced Age (ERP and Psychology Tests Analysis).]

The study analyzed ERPs in 37 healthy right handed subjects without neurological and psychiatric disorders. Young age group consisted of 18 persons aged 18 to 27; advanced age group included 19 persons aged 32 to 59. ERPs were recorded by 32 scalp electrodes according to 10-20% system. Two toned addball paradigm including standard and target tones was used for ERP-recording. The sound sequence was given to examinees without any preliminary instruction. Complex psychology testing included Stroop color and word test for the attention and interference assessment, and Wisconsin card sorting test. Significantly larger amplitude of N200 was detected in young persons in comparison to ones of advantage age. Wavelet-analysis revealed stronger wavelet-connections in frontal-central area on the time range of P300 in persons of advanced age vs. younger ones. The correlation of data of psychological tests examining executive functions was detected with latency of P300 in young examinees and with amplitude of P300 in advanced age ones. Obtained data suggests that switching from one activity to another is prevalence in young persons and focusing on a current activity in advanced age persons.

[Clinical/encephalographic syndrome of dopamine deficiency in patients with depressed consciousness after severe brain injury].

OBJECTIVE: To determine electroencephalographic signs of dopamine deficiency syndrome during the recovery after severe brain injury (SBI). MATERIAL AND METHODS: We studied 35 patients with SBI (23 men and 12 women, mean age 29 ± 13 years). RESULTS AND CONCLUSION: We identified a set of neurological symptoms (increased muscular tone of extrapyramidal type, rest tremor, autonomic disorders, which were most characteristic of the autonomic state, and some forms of mutism associated, according to current conceptions, with the dopaminergic system deficiency syndrome. This clinical picture was accompanied by stable EEG changes: an increase in the severity of beta activity of 13-14 Hz, enhanced in the frontal and anterior temporal areas, synchronized with equivalent dipole source localization in subcortical and frontal/basal areas. Dopamine deficiency regression syndrome was accompanied by an increase in beta EEG activity (from 13 to 16 Hz), but with the persistent abnormal enhancement of coherent hemispheric relations, especially in the occipital-temporal areas.

[The analysis of fMRT answer's individual variability at healthy examinees when opening eyes, motor and speech tests].

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.

[EEG-correlates of consciousness recovery after traumatic brain injury].

The aim of studies of patients in long-term posttraumatic unconscious state (PUS) was to outline prognostically significant EEG-markers of consciousness condition and an assessment of its dynamics orientation. We analysed outcomes of dynamic (from days to 16 years after trauma) EEG studies in 196 patients in TBI-caused PUS and different degrees of mental recovery: from chronic unconscious state up to clear consciousness. These results were compared to clinical protocols and data of MRI. It is revealed that dynamic features of EEC pattern (with the analysis of equivalent dipolar sources of separate components) allow to characterize the severity of patient's current state, to reveal the brain structures with the most expressed dysfunction, to define a zone of local cortical damage, and also the general direction of development of a traumatic illness (as though dynamics of a homeostasis of a brain). Frequency characteristics of EEG power spectrum (average frequency--an effective frequency strip) in a background and at reactions find the greatest predictive importance, especially at their assessment in 2-3 months after a trauma. The background interhemispheric EEG coherence (first of all, frontal) as the integrative characteristic of system brain activity, and its change at reactions to external incentives most reflect degree of consciousness oppression, dynamics and potential of its restoration. It was shown the high informational of the researches EEG changes to indifferent and functionally significant signs for an assessment of CNS functionality, and also of PUS pathogenesis.

[EEG and fMRI reactions of a healthy brain at active and passive movements by a leading hand].

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.

[Structural and functional peculiarity of brain activity to performance and imaginary motor tasks in healthy persons (EEG and fMRI study)].

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.

[The comparative analysis of changes of short pieces of EEG at perception of music on the basis of the event-related synchronization/desynchronization and wavelet-synchrony].

The going of present pilot study is an analysis of features changes of EEG short pieces registered from 32 sites, at perception of musical melodies healthy examinees depending on logic (cognizance) and emotional (it was pleasant it was not pleasant) melody estimations. For this purpose changes of event-related synchronization/desynchronization, and also wavelet-synchrony of EEG-responses at 31 healthy examinees at the age from 18 till 60 years were compared. It is shown that at a logic estimation of music the melody cognizance is accompanied the event-related desynchronization in the left fronto-parietal-temporal area. At an emotional estimation of a melody the event-related synchronization in left fronto - temporal area for the pleasant melodies, desynchronization in temporal area for not pleasant and desynchronization in occipital area for the melodies which are not causing the emotional response is typical. At the analysis of wavelet-synchrony of EEG characterizing jet changes of interaction of cortical zones, it is revealed that the most distinct topographical distinctions concern type of processing of the heard music: logic (has learned-hasn't learned) or emotional (it was pleasant-it was not pleasant). If at an emotional estimation changes interhemispheric communications between associative cortical zones (central, frontal, temporal), are more expressed at logic - between inter - and intrahemispheric communications of projective zones of the acoustic analyzer (temporal area). It is supposed that the revealed event-related synchronization/desynhronization reflects, most likely, an activation component of an estimation of musical fragments whereas the wavelet-analysis provides guidance on character of processing of musical stimulus.

[Comparison of reactive EEG changes and fMRI characteristics of brain health based on multivariate statistics].

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.

[Functional effects of transcranial electromagnetic stimulation (60 and 70 Hz) of the brain of intact rats and rats with acute brainstem damage].

Behavior and brain electrical activity of 79 male Wistar rats (intact and with acute experimental brainstem injury) were studied during the course of therapeutic transcranial electromagnetic stimulation (TEMS) with frequencies 60 and 70 Hz. In intact animals this effect was accompanied by a decrease in voluntary motor activity and increase in synchronization of the brain electrical activity, in particular, in the delta and beta1 frequency ranges. This inhibitory effect was similar to that of sleep. In the early period of acute experimental stem pathology, the TEMS course was accompanied by suppression of EEG signs of adaptive post-operative stress response and could lead to increased severity of the condition of an animal, along with the slowing of postoperative recovery. Cytomorphological evidence was obtained to the importance of vascular factor in the formation of cerebral reactions to TEMS.

[Long-latency components (N100, N200 and P300) of acoustic evoked potentials in prediction of mental recovery in severe traumatic brain injury].

The authors analyzed correlations of amplitude and latency levels of N100, N200 and P300 components of acoustic evoked potentials (AEP) registered during sonic stimulation and counting of target-oriented stimuli in 22 patients in vegetative state and mutism as an outcome of traumatic brain injury. Results were analyzed with association of electrophysiological findings with data of diffusion-tensor MRI. 55 healthy volunteers were included into control group. It is described that patients in vegetative state with formal recovery to the level of clear consciousness develop all three components of AEP in response to target-oriented tone. The instruction "to counts" leads to their better development. Patients with restoration to minimal level of consciousness produce all components during audition of sounds and only N100 and N200 in response to standard tone after instruction "to count". It is discovered that levels of amplitude have bigger correlation according to Spearman's criterion with outcome in comparison to latency. There changes are more prominent in N100 and N200 components rather in P300. In addition, after instruction "to count sounds" the registered changes between stages of vegetative state and mutism are significant for leads of left hemisphere, and during audition of sounds--for sagittal leads. The study showed correspondence of acquired changes with MRI data. Chronic unconscious state is associated with changes in corpus callosum (degeneration fibers) and corticospinal tracts in the brainstem. The data are discussed in light of hypothesis of the role of morphofunctional disconnections (brainstem-thalamus and interhemispheric) in impairment of attention and in genesis of different forms of posttraumatic unconscious state.

[Clinical and electroencephalographic effects of amantadine sulfate (PK-Merz) on consciousness disorders due to the severe traumatic brain injury].

It was carried out a complex clinical-neurological and electroencephalographic study of 12 patients with consequences of severe traumatic brain injury with changes in consciousness, motor deficit, higher tonus of voluntary muscles and cognitive disorders. The study was conducted before, during and after treatment with amantadine sulfate. There were correlations between changes in mental and neurological status of patients and basic EEG.

[Possibilities of wavelet-syncronization method for estimation of the spatial distribution of components of auditory evoked potentials in healthy subjects].

Event-related potentials (ERP) are informative indicators of higher nervous activity of healthy people and patients in pathological states. Traditionally, methods of ERP processing include peak-time characteristics, topographical mapping and localization of equivalent dipole sources. At the same time, estimation of ERP synchronization is complicated by a short duration of the process. The wavelet analysis makes it possible to overcome the disadvantages of the traditional Furrier analysis and to calculate characteristics of ERP synchronization, in particular, phase synchronization. A new approach to estimation of the auditory ERP in healthy persons is proposed in the article. The method is based on the analysis of phase wavelet-synchronization of ERP individual components under conditions of differentiation of different degrees of attention concentration in healthy persons.

[Complex approach to the treatment of the diskal hernia of lumbosacral spine].

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-EEG estimation of cerebral reactivity to motor tasks in patients with brain tumors].

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.

[Healthy person's cerebral reactions to the rhythmic transcranial magnetic stimulation of different intensity].

At 8 healthy examinees-volunteers of 22-25 years the functional effects of super-threshold (above 1.2 T) and subthreshold (70-80% of a motor threshold) rTMS of premotor cortexes medial departments were compared. Functional brain activity changes were estimated (before and 1 hour after stimulation) by comparing data including neuropsychological testing, visual and spectral-coherent EEG-analysis, and also haemodynamic parameters. The number of the work's problem included selection of activating orientated stimulation's frequency, and also specification objective EEG--criteria of efficiency rTMS. It is established the effect of EEG-analysis during different frequency photostimulation for a choice of activating rTMS. The received results reveal EEG-coherence as one of the most informative characteristics of cerebral neuro-dynamics under rTMS-influence. Dependence of stimulation's functional effects (activated or brake character) from initial level of the intercentral coherent communications is noted. It is revealed that rTMS of the healthy examinees causes certain changes of functional activity of a brain, distinct from placebo-effects. rTMS-effect dependent on intensity (super--or sub-threshold), and also from features of an initial intercentral rations. More expressed functional changes are observed in the left hemisphere. It is shown big by reactance of the left hemisphere on this influence. In formation of brain responses on rTMS the active role of the vascular factor is shown.

[Study of the role of the right and left orbitofrontal cortex in compensatory cerebral reactions after acute brainstem damage].

Significance of the right and left orbitofrontal cortex (OFC) in recovery after acute brainstem lesion (at the level of n. Deiters) was investigated using rat model of complex brainstem-orbitofrontal cerebral damage. It was found that the right-side lesion of the OFC combined with isolated brainstem damage resulted in aggravation of the animal condition and highly probable lethal outcome within the first two weeks after surgery (because of the brain circulation disorder of hemorrhagic type). It may be associated with sympathetic activation. It is suggested that a certain "stimulation" of the left OFC (as the effect of its incomplete destruction) involves a parasympathetic compensatory reaction that allows animals with a severe brainstem pathology to survive. It is shown that, with the general nonspecific tendency to postoperative increase in emotionality, the greatest shifts in the emotional sphere take place under conditions of a combined damage of the brainstem and left OFC.