[Speech and motor disorders in Rett syndrome]

Rett syndrome (RS) is a severe genetically conditioned disorder of an early childhood with an definite clinical phenotype in girls. Motor and speech disturbances are noted as the essential part of RS clinical picture. The variability of motor dysfunction and degree of speech deterioration were noted at different stages of the illness. The aim of the present investigation was to study dynamics of both speech and motor disturbances during 2-5 years of the course of the illness and to analyze a correlation of motor and speech functions' disorders. The study was performed in 50 girls with classical RS aged from 12 months to 14 years. The data obtained show a gradual involvement of different brain cortex structures in pathological process during the course of RS (especially of frontal and temporal-parietal regions) at the early stage of the illness and subsequent spread of the pathological process with successive involvement of subcortical structures, cerebellum, brain stem and eventually spinal cord. The neurophysiological investigation showed a strong correlation of speech and motor disturbances' degree with the EEG parameters. The level of theta-activity was significantly lower and the level of alpha- and beta-activity was significantly higher in EEGs of RS patients with more preserved speech and motor functions. In discussion mechanisms of motor and speech disturbances in RS were considered.