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Biomedical subjects

R I Machinskaia

Publications and source records attributed to R I Machinskaia.

At least 19 recordsLinked to original sources
PubMed2000

[Pathogenetic mechanisms of stuttering].

A complex study including neurologic, psychologic, neurophysiologic and EEG investigation of 33 stutter patients was performed to determine pathogenetic mechanisms of stutter. All clinical data obtained were presented by means of structural schemes based on topical diagnosis. All the symptoms were divided into blocks containing information about functional state of separate CNS structures and systems, character and degree of observed deviation. The analysis of obtained results permits to consider dysfunction of hypothalamus-hypophysis-adrenal system under emotional stress as a cause of stutter. Peculiarities of the neurohumoral regulatory system development determine both age and sex specificity of the considered syndrome.

Adolescent↗
PubMed1999

[EEG diagnostic potential in the estimation of the severity and sequelae of ischemic stroke].

Simultaneous consideration of both electroencephalographic and neurologic data as well as the results of both computer and emission computer tomography in patients with consequences of ischemic stroke during a process of neurorehabilitation gave chance for more accurate definition of organic origin of some EEG phenomena. It was found that a damage of the conductive pathways between the cortex and subcortical structures associated with disorders of blood circulation in the area of the middle cerebral artery was accompanied by local disorders in electric activity of the cortex mainly in form of polymorphic waves of theta- and delta-ranges and groups of theta-waves. Besides, a character of the slow waves depended on the size of the damage and on the degree of a decrease of blood circulation in the area of the damage. A decrease of the damage focus and improvement of circulation during restoration process was accompanied by changes in local deviations in cortical electric activity: polymorphic slow waves activity was replaced by sharp waves of alpha- and theta-ranges. Location of the changes of electric activity in caudal regions of the cortex is an unfavourable prognostic sign for restoration of motor activity in patients with ischemic stroke.

Adolescent↗
PubMedDate not supplied

[EEG-Expert automated diagnostic system].

The system is designed to describe and collect data of virtual analysis of electroencephalograms (EEG), as well as to make an expert conclusion on the functional status of the brain and its particular regions. The system includes three parallelly operating systems in the form of a EEC visual analysis schedule as a questionnaire. A programme provides recommendations for describing the level, pattern, and magnitude of the changes detected. Another programme automatically makes an EEC description and a conclusion on cerebral function in conformity with the signs given in the questionnaire and displays them on the screen and sends them to the print. The system may be used for practice in the in- and outpatient settings, for training and postgraduate training of young specialists, and for researches.

Adolescent↗
PubMedDate not supplied

[Neurophysiological mechanisms of voluntary attention: a review].

The review is focused on attention as behavior-controlling process. Neurophysiological, electrophysiological and neuropsychological studies of different brain structures during voluntary attention are analyzed. These data show that selective voluntary attention modulates activity of sensory specific cortical zones involved in relevant signal processing. Fronto-thalamic system consisting of prefrontal cortex and thalamic mediodorsal nuclei is shown to be main source of top-down selective modulation of voluntary attention. The review proposed the hypothetical model of selective cortical activity modulation during voluntary attention based upon the available data and evidence of own electroencephalographic studies.

Animals↗
PubMedDate not supplied

[Spatial synchronization of cortical electrical activity at different stages of visual set in preschool children].

Changes in the alpha-rhythm synchronization were revealed at different stages of cognitive visual set in 5- to 7-year-old children. We found a clear-cut correlation of these changes with set plasticity. In children with a plastic set, the EEG synchronization between the frontal and other brain regions substantially increased in the period of set-shifting (the actualization stage). At the set extinction stage, after set-shifting has already taken place, the EEG-synchronization becomes minimal. On the contrary, in children who formed a rigid set, EEG coherence considerably increases at the set extinction stage. This finding suggests that the rigid set still affects the cognitive activity even after (judging from oral reports) the set shift has been completed. The age-related differences in cognitive set formation clearly correlate with the time course of the EEG synchronization between the frontal and other brain regions. We think that the ability to form a plastic visual set depends on the frontal cortex maturation, which occurs at the age of 6-7 years, and its age-related effect on the brain cognitive functions.

Age Factors↗