Language and reading abilities of children with autism spectrum disorders and specific language impairment and their first‐degree relatives

Abstract

SCIENTIFIC ABSTRACTAutism spectrum disorder (ASD) and specific language impairment (SLI) are developmental disorders exhibiting language deficits, but it is unclear whether they arise from similar etiologies. Language impairments have been described in family members of children with ASD and SLI, but few studies have quantified them. In this study, we examined IQ, language, and reading abilities of ASD and SLI children and their first-degree relatives to address whether the language difficulties observed in some children with ASD are familial and to better understand the degree of overlap between these disorders and their broader phenotypes. Participants were 52 autistic children, 36 children with SLI, their siblings, and their parents. The ASD group was divided into those with (ALI, n=32) and without (ALN, n=20) language impairment. Relationships between ASD severity and language performance were also examined in the ASD probands. ALI and SLI probands performed similarly on most measures while ALN probands scored higher. ALN and ALI probands' language scores were not related to ADI-R and ADOS algorithm scores. SLI relatives scored lowest on all measures, and while scores were not in the impaired range, relatives of ALI children scored lower than relatives of ALN children on some measures, though not those showing highest heritability in SLI. Given that ALI relatives performed better than SLI relatives across the language measures, the hypothesis that ALI and SLI families share similar genetic loading for language is not strongly supported. Keywordsautism spectrum disorder; specific language impairment; parents; siblings; broader phenotype; genetics; language; reading INTRODUCTIONThere is a long-standing debate in the literature about the extent of overlap between the language phenotypes of autism spectrum disorder (ASD) and specific language impairment (SLI) and whether these deficits arise from similar genetic bases (for review, see Williams et al., 2008). Studies have attempted to address this issue by investigating language abilities in first-degree relatives. Atypical language, or a broader language phenotype, has been described in family members of individuals with ASD and SLI, but few studies have NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript quantified these deficits using standardized language measures, particularly those assessing structural aspects of language. Such studies are necessary to test the specificity of the language phenotypes in ASD and SLI as well as identify which aspects may be genetically mediated. Overlap Between ASD and SLIAutism and SLI are two developmental disorders that share language as a deficit. In both disorders, concerns are typically raised during the toddler years (Dahlgren & Gillberg, 1989; Tager-Flusberg & Cooper, 1999). Autism and SLI are both considered spectrum disorders (Bishop, 1989; Gillberg & Coleman, 2000;Resnick & Rapin, 1991), and this is supported by the considerable heterogeneity in language abilities observed in affected individ...

A Comprehensive Examination of Reading Heterogeneity in Students with High Functioning Autism: Distinct Reading Profiles and Their Relation to Autism Symptom Severity

“…The most prominent difference was that no dyslexic profile emerged in our study whereas this subgroup made up 35.5% of the poor readers in their sample. This finding is consistent with previous studies of reading in samples with ASD (Lindgren et al 2009;Lucas and Norbury 2014;Norbury and Nation 2011). Similar to these prior studies, poor word reading and decoding in our sample was generally associated with structural language difficulties as well as language and reading comprehension impairments, not as a stand-alone dyslexic profile.…”

“…However, the two measures reported to be sensitive markers of language impairment, Nonword Repetition and Recalling Sentences (Condouris et al 2003;Norbury and Nation 2011;Rapin et al 2009), posed a challenge for many of these children. Therefore, in this subgroup, word recognition abilities did not necessarily align with structural language abilities as reported in prior studies of reading and language in ASD (Lindgren et al 2009;Lucas and Norbury 2014;Norbury and Nation 2011). Furthermore, children in this profile displayed higher-level linguistic comprehension deficits ranging from approximately 1 to nearly 2 standard deviations below average across the auditory reasoning/inference, story recall, and reading comprehension measures.…”

“…Empirical evidence exists to demonstrate that both word recognition and linguistic comprehension account for substantial unique variance in reading comprehension for children with ASD, supporting the Simple View in this population (Jones et al 2009;Lindgren et al 2009;Nation et al 2006;Norbury and Nation 2011;Ricketts et al 2013). Similar to the subtypes described by Catts et al (2003) with a typically developing reading sample, many samples with ASD have displayed profiles comparable to poor comprehenders, or hyperlexics, who demonstrate adequate word decoding alongside poor language and reading comprehension (e.g.…”

“…Similarly, in several other studies, word recognition skills have been shown to correlate with language abilities, reporting subgroups of children with poor word recognition associated with poor oral language skills (e.g. Brown et al 2013;Jacobs and Richdale 2013;Lindgren et al 2009;Nation et al 2006;Norbury and Nation 2011;Ricketts et al 2013). Three studies have reported that children with ASD who have age-appropriate language skills scored significantly higher than those with language impairments on standardized measures of reading comprehension, word recognition, and decoding (Lindgren et al 2009;Lucas and Norbury 2014;Norbury and Nation 2011).…”

“…There is some evidence that beyond reading comprehension disturbance, there are different profiles of readers in school-aged children with ASD (e.g., Brown et al 2013;Jones et al 2009;Nation et al 2006). In addition, research has delineated language subgroups in children and adolescents with ASD (Rapin et al 2009;Tager-Flusberg and Joseph 2003), and language impairments have been linked to reading difficulties in this population (Lindgren et al 2009;Lucas and Norbury 2014;Norbury and Nation 2011). However, the relation between these language and reading subgroups was previously unexamined using comprehensive reading and language batteries.…”