After a stroke, in 80% of patients developed disorders of motor control, including paresis, syndromes of spasticity and pathological synergies. Restoration of motor control is caused by activation of primary motor representations around the perilesional region, while development of maladaptive models of motor control is relative with complex process of reorganization, both the affected and unaffected hemispheres. According to TMS, paresis regresses with the restoration of corticospinal innervation. While development of functional compensatory models which calls are «maladaptive models of motor control» are causes by activation of secondary ipsilateral motor representations, hyperactivation of motor representations of the contralateral hemisphere and release of subcortical activity. For mapping of complexity of brain plasticity in neuroscience are using the combination of TMS and EEG. The aim of the topic is to study the reorganization of bioelectrical activity of the brain using the complementarity of tms and eeg methods, among patients with cortical ischemic stroke with varying severity. In the study we described the results of examination, conducted by TMS and EEG methods, of 21 patients with chronical ischemia I-II stages without a neurological deficiency and 63 patients with the consequences of ischemic stroke with cortical localization. As a result of the research carried out by the method of TMS, three types of pathophysiological reactions were found depending on the state of corticospinal innervation, which resulted in the distribution of the patients into three groups of the study. Patients of the first study group (SG) are characterized by a moderate decrease of corticospinal innervation – up to 35% and a pronounced development of segmental hyperexcitability, bilateral decrease in the power of Beta-1 and Beta-2 rhythms, while maintaining the total frequency of the Alpha rhythm and the lack of release of slow-wave activity. In the study of corticospinal innervation among patients of second SG, was found a significant decrease of parameters up to 64%, while segmental hyperexcitability was not registered. The bioelectrical activity of brain are characterized by disorganization of Alpha rhythm with the release of subcortical activity, according to Delta and Theta rhythms bilaterally in a few regions, with maintaining the power of Beta rhythm in the central part of the ipsilateral and contralateral hemispheres. Patients of the third SG are characterized by the absence of cortical evoked motor potential, including in the trial with facilitation, and the most pronounced segmental hyperexcitability among the study groups. Patients with right hemispheric stroke are characterized by disorganization of physiological cortical activity in both hemispheres according to Alpha rhythm, and release of subcortical activity according to Delta and Theta rhythms, and suppression of the ability to reorganize and learn according to Beta rhythms, which generally indicates a low control and even the development of maladaptive compensatory models. Patients with left hemispheric stroke are characterized by disorganization of physiological cortical activity, according to Alpha rhythm, and release of subcortical activity, according to Delta and Theta rhythms, only in the affected hemisphere. At the same time, the preservation of Beta-1 and Beta-2 rhythms in the central regions of the contralateral hemisphere indicates its dominant role in the reorganization of motor control, which corresponds to the literature on the role of the contralateral hemisphere in compensating proximal movements through similar models of motor control. Mild injury of CSI are characterized by the improvement of the physiologically networks of both hemispheres in the process of recovery of the affected brain. The severe injury of CSI are characterized by the involvement to maladaptive reorganization of the brain both ipsilesional, contralesional hemispheres and subcortical structures. Complete injury of CSI are accompanied by the activation of the contralateral hemisphere in the left hemispheric localization of the stroke and the dominance of subcortical activity in the right hemisphere stroke. The release of subcortical activity, in the form of an increase in the power of the slow rhythms of Delta and Theta, increases in the groups according to the degree of KST damage, as shown in groups 2 and 3.
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