Specific language impairment (SLI) in children is characterized by severe and persistent difficulties in acquiring a native language, unrelated to intellectual disability, physical limitations, or psychosocial deprivation. The etiology of SLI, in particular the role of neurocognitive processes such as learning and information processing, is poorly understood. Progress in this domain is difficult because of the large etiologic and phenotypic heterogeneity of the SLI population.
Here, we propose to address this challenge by examining a population with developmental language impairment resulting from a uniform etiology: the 22q11.2 deletion (22q11DS). Children with 22q11DS display delayed language development, and learning- and information processing deficits similar to SLI. The fact that all 22q11DS share the same genetic etiology provides us with a unique opportunity to identify the mechanisms underlying this language disorder.
Our program has three interrelated objectives: (1) to provide a detailed description of language development in 2-6-year old children with 22q11DS; (2) to examine neurocognitive mechanisms associated with language acquisition in children with 22q11DS, with special reference to implicit learning and executive functions; (3) to describe the language skills of adolescents with 22q11DS and investigate its possible relationship to psychopathology, in particular the elevated genetic predisposition (25-30%) for schizophrenia. The synthesis will investigate what the language profile of 22q11DS and its neurocognitive underpinnings tell us about developmental language disorders and general language acquisition. This program will provide further clues into the etiology of language impairment in both 22q11DS and SLI, and can be used to inform coaching and professional intervention.
Full program proposal: NWOGWVC_22q11_Wijnen_2016_def_Sep6