Purpose: Individuals with proximal 16p11.2 copy number variants (CNVs), either deletions (16p11.2DS) or duplications (16p11.2Dup), are predisposed to neurodevelopmental difficulties and disorders, such as language disorders, intellectual disability, and autism spectrum disorder. The purpose of the current study was to characterize language…

This study investigated to what extent the Peabody Picture Vocabulary Test (PPVT-4) is a reliable tool for measuring vocabulary knowledge of English as a second language (L2), and to what extent L1 characteristics affect test outcomes. The PPVT-4 was administered to Dutch pupils in six different age groups (4-15 years old) who were or were not…

We examined the response to a phonics through spelling intervention for children with developmental dyslexia in word and pseudoword reading efficiency and word spelling. Furthermore, we investigated to what extent the response to the intervention is robust across different cognitive profiles (phonological awareness, rapid automatized naming, and…

Listening comprehension is important for daily communication and at school, yet relatively little is known about the variables contributing to listening comprehension, especially in the upper elementary years. The aim of this study was to explore whether vocabulary, verbal memory, but also self-efficacy and self-reported concentration contribute…

Formal thought disorder (FTD) is a disruption in the flow of thought and a common feature in psychotic disorders and autism spectrum disorder (ASD). Executive dysfunction has often been associated with FTD, yet for ASD convincing evidence is lacking. This study investigated FTD and three core executive functions in 50 young children and…

This longitudinal study investigated to what extent the acquisition of cognates among bilingual children depends on the degree of cross-language similarity and intensity of exposure to the tested language, and whether children's sensitivity to cognates with different degrees of cross-language similarity changes over time. For three consecutive…

The mental lexicon plays a central role in reading comprehension (Perfetti & Stafura, 2014). It encompasses the number of lexical entries in spoken and written language (vocabulary breadth), the semantic quality of these entries (vocabulary depth), and the connection strength between lexical representations (semantic relatedness); as such, it…

While stress is a common experience for parents caring for a child with a developmental disability, current measures fail to distinguish between general stress in parents and the demands of parenting and perceptions of parenting skills (parenting stress). This study examined differences in "parenting stress" reported by parents of…

Do children who go on to develop dyslexia show normal verbal and nonverbal development before reading onset? According to the aptitude-achievement discrepancy model, dyslexia is defined as a discrepancy between intelligence and reading achievement. One of the underlying assumptions is that the general cognitive development of children who fail to…

In a longitudinal genetic study we explored which factors underlie stability in verbal and nonverbal abilities, and the extent to which the association between these abilities becomes stronger as children grow older. Measures of verbal and nonverbal IQ were collected in Dutch twin pairs at age 5, 7, 10, 12 and 18 years. The stability of both…