Words Listening Related Electroencephalography Reactivity in Children of Preschool and Primary School Age

An analysis was made of event-related changes in the electroencephalogram (EEG) spectrum during the auditory perception of nouns in 83 typically developing children aged 4 to 10 years, including 50 children of preschool age and 33 children of primary school age. Following intergroup differences were revealed: in preschool children, neuronal systems are more involved in word processing, the activity of which is reflected in extensive desynchronization of alpha and synchronization of theta activity in the frontal zones of the left hemisphere. The EEG reactivity of primary school children is characterized by bilateral and more pronounced theta synchronization, which indicates an increased intensity of lexico-semantic operations, as well as a decrease in the background and an increase in the evoked theta activity. In children of this group, EEG synchronization in the beta range was also observed, represented by separate flashes and most pronounced in the frontal leads, which is typical for more mature speech processing mechanisms. The study results are important for clarifying the mechanisms of speech understanding in typically developing preschool and primary school age children.