The study of functional organization of the brain of people with sensory defects is an urgent problem today. Orthostatic test used in clinical practice to study the excitability vasomotor centre of the medulla oblongata. Since this center is part of the reticular formation of the brain, we can assume the features of functional changes in EEG brain hard-of-hearing teenagers during orthostatic test performance. The studied teenagers (12 - 15 years) were divided into two groups: group of teenagers with hearing impairments formed on the basis of Kherson boarding school № 29 for children with impaired hearing and was 82 individuals with sensorineural hearing loss II - III degree (40 boys and 42 girls). The control group consisted of 80 students of the school № 30 of Kherson - teenagers with normal hearing (40 boys and 40 girls). All surveyed teenagers were right-on self-assessment and manual tests. Conducted analysis zonal distribution of normalized spectral power main frequency ranges of electrical activity in the brain functional state of rest and during orthostatic test. Numerous studies show that the transition from horizontal to vertical position runs a number of adaptive vascular responses: decrease in percussive volume, decreased systolic blood pressure, increased heart rate. This indicates the excitation vasomotor centre of the medulla oblongata. The EEG normal teenagers during orthostatic test, we observed an increase in slow-activity by increasing the activity of delta-rhythm and reducing the representation of high-activity by decreasing the alpha-rhythm. The transition from horizontal to vertical position vasomotor centre accompanied by excitation of the medulla oblongata. Vasomotor centre is part of the medulla oblongata reticular formation of the brain. Stimulation vasomotor centre of the medulla oblongata, and hence the reticular formation of the brain will cause a slow-activity and correspondingly reduce the high-frequency activity that we observe in the EEG normal teenagers during orthostatic test. The EEG hard-of-hearing teenagers we saw a different picture: reducing the representation of delta-rhythm, increasing the representation of theta-rhythm on EEG girls, increasing the representation of alpha- and beta-rhythm during orthostasis. In hard-of-hearing teenagers as a result of a decrease in sensory defect sensory inflow. Perhaps an increase of vascular baroreceptors during the transition from horizontal to vertical position increases the number of afferent information, so we are seeing an increase in the tone of the cerebral cortex in hard-of-hearing teenagers. The results of electroencephalographic examination hard-of-hearing and normal teenagers during orthostasis. It was found that the orthostatic test caused a decrease in normalized spectral power of delta rhythm of EEG hard-of-hearing teenagers compared with the functional state of rest; EEG normal teenagers, on the contrary, an increase the volume of the delta rhythm EEG during orthostasis. It was found that the transition from the horizontal to the vertical position has caused an increase the volume of the alpha rhythm in the EEG hard-of-hearing teenagers, whereas EEG brain normal teenagers observed the opposite phenomenon. It was found that the decrease in the auditory sensory causes changes in the brain neurodynamic organization and the interactions between parts of the brain in the implementation of adaptive responses such as orthostasis.
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