The Functional State of the Cortex and Brainstem Regulatory Structures in Children with Speech Development Disorders

EEG recordings of 4- to 12-year-old children with general speech underdevelopment, dysgraphia, dyslexia, and sensorimotor and motor alalia were examined. EEG structural analysis improved the understanding of the neurophysiological mechanisms of these disorders. In most subjects, the left hemisphere was involved more than the right one. All groups were characterized by dysfunction or functional immaturity of the frontothalamic regulatory system or nonspecific activation deficiency. When dysfunction of brainstem regulatory structures was combined with impaired cortical rhythmogenesis, which reflects the functional immaturity of the cortex, this aggravated the defect and impeded corrective pedagogical measures.