Identifying Areas of Overlap and Distinction in Early Lexical Profiles of Children with Autism Spectrum Disorder, Late Talkers, and Typical Talkers

This study compares the lexical composition of 118 children with autism spectrum disorder (ASD) aged 12 to 84 months with 4626 vocabulary-matched typically developing toddlers with and without language delay, aged 8 to 30 months. Children with ASD and late talkers showed a weaker noun bias. Additionally, differences were identified in the proportion of nouns and verbs, and in the semantic categories of animals, toys, household items and vehicles. Most differences appear to reflect the extent of the age differences between the groups. However, children with ASD produced fewer high-social verbs than typical talkers and late talkers, a difference that might be associated with ASD features. In sum, our findings identified areas of overlap and distinction across the developing lexical profiles.