Comparison of Linguistic Error Production in Conversational Language Among Boys With Fragile X Syndrome + Autism Spectrum Disorder and Autistic Boys.

Researchers compared how boys with Fragile X syndrome and autism make grammar mistakes when talking, versus boys with just autism. Both groups made similar types and amounts of errors, but both groups left out more words when speaking compared to other children their developmental age. This suggests that leaving out words during conversation might be a specific language pattern in autism.

This comparative study examined grammatical errors in conversational language samples from 39 school-age boys: 20 with Fragile X syndrome plus autism spectrum disorder (FXS + ASD) and 19 with autism only. Participants were matched on autism severity, and their language samples were analyzed for word and utterance-level errors and omissions. Both groups showed similar error rates across categories but produced significantly more omissions compared to mental age-matched and mean length of utterance-matched reference groups. The findings suggest that omissions in conversational speech may represent a specific grammatical marker associated with the autism phenotype, regardless of underlying genetic condition.

Speech-language pathologists should pay particular attention to word omissions in conversational speech when assessing and treating autistic children. This pattern appears consistent across different autism presentations and may be a useful clinical marker for identifying language difficulties.

Small sample size (39 participants total) limits generalizability. Study focused only on school-age boys, excluding girls and other age groups. Cross-sectional design prevents understanding of developmental trajectories. Limited to conversational language samples only.

Expressive language impairments are common among school-age boys with fragile X syndrome (FXS) and autistic boys. Given the high co-occurrence of autism spectrum disorder (ASD) among individuals with FXS, cross-condition comparisons can elucidate the specificity of such impairments as they relate to ASD. Language samples can provide fruitful information regarding individuals' grammatical skills in less structured formats relative to standardized measures. This study examined grammatical errors produced during a conversational language sample among 20 boys with FXS and co-occurring ASD (FXS + ASD) and 19 autistic boys matched on ASD severity.

Language samples were coded for omissions and errors at the word and utterance levels. Participants' grammatical errors were also compared to separate mental age-matched and mean length of utterance-matched boys from a reference database. Boys with FXS + ASD and autistic boys produced similar rates of errors across all categories. Relative to their matched comparison groups, boys with FXS + ASD and autistic boys produced significantly more omissions during conversation.

These findings suggest that omissions may be a unique grammatical marker associated with the ASD phenotype. Further examination of omissions across diagnostic groups would aid in clarifying the specificity of omissions in the language phenotype of ASD.