Background and aims: A substantial minority of autistic individuals score within typical ranges on standard language tests, suggesting that autism does not necessarily affect language acquisition. This idea is reflected in current diagnostic criteria for autism, wherein language impairment is no longer included. However, some work has suggested…

Purpose: Expressive language impairments are common among school-age boys with fragile X syndrome (FXS) and autistic boys. Given the high cooccurrence 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…