Language phenotypes in children with autism spectrum disorder, expressive language disorder, and typical language development.

The aim of this study was to compare language abilities in 4-6-year-old Georgian-speaking children with typical language development (TLD), expressive language disorder (ELD), and autism spectrum disorder (ASD). Language linguistic components, such as phonology, semantics, syntax, morphology, and pragmatics, were examined along with verbal behavior types like "mand," "tact," "echoic," and "intraverbal." Our sample comprised 148 children, with a gender distribution of 50 girls and 98 boys. Significant differences were observed in the application of various parts of speech across the three groups. Children with ELD were found to use pronouns more frequently compared to TLD and ASD groups. Conversely, children exhibiting typical language development displayed a greater usage of conjunctions and particles than the other groups. Notably, linguistic error patterns varied across groups: children with ELD predominantly committed errors in phonetics and morphosyntax, while children with ASD had more pragmatic errors and also struggled with morphosyntax. Moreover, the ASD group was found to use "mands" and "echoics" more frequently than both the TLD and ELD groups.