The first major objective of the current project is to uncover language growth, possible language impairments and their specific developmental pathways in very young children at risk for ASD. To this end, language development will be analyzed in great detail. Until now, language in these children has been mainly researched by examining the number of words they produce and understand. Language, however, contains more elements by which different impairments are specified. Therefore, in this project we will include language form (phonology, morphology and syntax), language content (semantics) and language use (pragmatics) in order to discover specific shortcomings in expressive, receptive and pragmatic language at different time points. The second main objective is to uncover possible precursors (social-communicative abilities) of language development and characteristics of parent-child interaction in children at risk of ASD. Thereby, we want to determine the predictive value of these precursors and the possible mediating role
of parent-child interaction on the development of expressive, receptive and pragmatic language abilities. Knowledge of which precursors in the early development of siblings influence the different language abilities, offers possibilities to start an intervention before language is largely acquired. Due to a lack of research in this domain however, this information is currently unavailable. In order to investigate and better understand the developmental pathways and precursors of language development and the characteristics of parent-child interaction early in life, a longitudinal study of children with ASD starting in the first months of life is required. Given the high recurrence rate,
siblings of children with ASD are a very suitable group to study early characteristics of ASD and to increase our knowledge on the early development of language and its precursors in children developing ASD, the BAP or other developmental delays. Furthermore, the development of different types of language impairment and its precursors will be investigated. This will also allow us to evaluate the potential value of language and its precursors for early diagnosis and the possible impact on early interventions.