Lexical Knowledge in School-Aged Children with High-Functioning Autism Spectrum Disorder: Associations with Other Linguistic Skills

Abstract

Background: This quasi-experimental comparative group study examined vocabulary knowledge and its associations with other language skills in Greek-speaking children with high-functioning Autism Spectrum Disorder and mild language impairment (HF-ASDLI) and typically developing (TD) peers. Methods: 25 children aged 7–10 years old participated in each group. Groups were matched in age, gender, and non-verbal IQ. Naming and word definition tasks were used to evaluate vocabulary knowledge in both groups. Results: Groups did not differ in the naming task; however, children with HF-ASDLI scored lower in the definition task. Both vocabulary tasks positively correlated with morpho-syntactic and overall language ability in both groups, although a significant positive correlation was detected between vocabulary knowledge and informational competence exclusively in the group with HF-ASDLI. Conclusions: Being in the HF-ASDLI group and having narrative ability significantly predicted participants’ performance in the definitions task, indicating that language impairment better explains vocabulary difficulties. These results agree with findings from the English language.