21202
Language Abilities at the Age of 36 Months in Children at Risk for Autism Spectrum Disorder
Research shows that language problems are highly prevalent in children with autism spectrum disorder (ASD). The profile of language problems, however, is variable across children and changes with age. Almost all children with ASD show significant difficulties in pragmatics. On the contrary, only some children with ASD show difficulties regarding vocabulary and grammatical language skills. Language ability is a critical element in the overall development and quality of life of individuals with ASD. Furthermore, the quality of early language and speech development is highly predictive of adult outcome. Younger siblings of children with ASD have a higher risk of developing the disorder themselves, a mild expression of the disorder and/or other developmental problems such as delayed language development or atypical general development. It is therefore important to investigate possible language problems and their locus in high-risk siblings.
Objectives:
The aim of the current study was to systematically investigate language at 36 months in children at high and low risk for ASD by looking into different linguistic levels of language.
Methods:
Younger siblings of children with ASD (high-risk siblings, n = 58) and typically developing children (low-risk siblings, n = 65) are followed as part of a larger longitudinal study. Preliminary analyses were conducted with a subsample of 17 high-risk siblings and 16 low-risk siblings. At 36 months expressive and receptive language abilities were assessed using the Dutch version of the Reynell Developmental Language Scales (RTOS). Scores for the different linguistic levels were acquired by combining item scores on the RTOS. Regarding receptive language, scores were obtained for three linguistic levels: lexicon, syntax and semantics. Concerning expressive language, scores for six linguistic levels were calculated: lexicon, morphology, syntax, semantics, pragmatics and grammar (morphology and syntax).
Results:
High-risk siblings showed similar age equivalents when compared to low-risk siblings on receptive, expressive and total language as measured by the RTOS. Nonetheless, differences were found at linguistic level. High-risk siblings scored significantly lower on lexicon (U = 58.5, p = .004) and syntax (U = 81.5, p = .049) in receptive language and on lexicon (U = 74.0, p = .043) in expressive language.
Conclusions:
At the age of 36 months language abilities of high-risk siblings were in general similar to language abilities of low-risk siblings. Despite similar general language scores, high-risk siblings did show significantly lower scores with regard to lexicon (receptive and expressive) and syntax (receptive). It seems to be important to look at the language abilities of high-risk siblings in detail as difficulties might be missed otherwise. In contrast to what was expected from the literature no significantly lower scores were found for pragmatics and semantics. Results of an extended sample of low-risk and high-risk siblings as well as the diagnostic outcome of the latter group will be presented at the conference.