Tarasova O. Brain electric activity of hard of hearing children of primary school age.

The thesis work is dedicated to study of parameters of brain electric activity of children of the age of 7-9 years having the sensorineural deafness of the II-III degree. EEG was recorded in the state of functional calmness, under eyes opening, under photostimulation with frequency of 4, 6, 9, 12 s-1 and under hyperventilation. It was shown that in the state of functional calmness there are differences in electric activity organization of hard of hearing children and children with normal hearing that indicates the functional immaturity of brain-cortex of hard of hearing children. It was revealed that that hard of hearing children have specific weight of delta- and teta-rhythms that is bigger than normal one; greater intensity of brain electrogenesis in ?, ?, ? and ?-bands; geometrical regularity of different zones of brain in delta and teta-bands; medium frequency of the dominant rhythm is lesser than the age norm. The hard of hearing children in response to light activation react in most cases with incomplete depression of alpha rhythm. Under photostimulation hard of hearing boys and girls adopt rhythms with frequency of 4, 6 s-1 better, whereas children with normal hearing - of 9, 12 s-1. Hyperventilation has revealed the signs of immaturity of fronto-thalamic regulating system as well as the dysfunction of lower parts of brainstem of hard of hearing children.