Understanding Speech in Primary Schoolchildren with Autism Spectrum Disorders and Its Relationship with EEG Characteristics

The article discusses heterogeneity of autism spectrum disorder (ASD) in terms of the severity of autistic manifestations, cognitive, and speech abilities in children with different levels of functioning. The results of a study of speech understanding at the level of phonology, vocabulary, morphosyntax, and discourse in primary schoolchildren with ASD are presented. The study has revealed correlations between the severity of autistic manifestations of a socio-communicative nature and nonverbal IQ with various aspects of speech understanding. Comparison of the correlations in the subgroups of children with different levels of functioning detected the differences between the subgroups, indicating different mechanisms of disorders. The differences of EEG spectral characteristics in children with ASD compared with the age norm and characteristics in the studied subgroups are shown. The differences in EEG spectral characteristics have been found between subgroups with ASD with different levels of functioning: the subgroup with less pronounced disorders is characterized by a higher index of β 2 -activity, while the subgroup with more pronounced disorders, by a higher index of slow-wave activity.