Differentiation hypotheses concern changes in the structural organization of cognitive abilities that depend on the level of general intelligence (ability differentiation) or age (developmental differentiation). Part 1 of this article presents a review of the literature on ability and developmental differentiation effects in children, revealing…

Goals: This study examined: (a) crystallized/fluid intelligence trajectories of adolescents and adults with Down syndrome; and (b) the contribution of endogenous (health, activities of daily living--ADL) and exogenous (cognitively stimulating leisure activities) factors on adults' intelligence with age. Method: Four cohorts (N = 80) with Down…

Despite the lasting interest towards the relationship between intelligence and creativity, comparably less attention is paid to its age-related changes. Our paper considers the organization of fluid intelligence and psychometric indicators of creativity and is based on the experimental data obtained for children aged 11 (n = 99) and for young…

The goal of this study was to test nonverbal intelligence and neighborhood social capital as protective factors against future delinquency in early adolescent youth placed at risk by virtue of their involvement in childhood conduct problems. Analyzing longitudinal data from 3,028 youth (1,565 boys, 1,463 girls) in one cohort of the Longitudinal…

Background: Understanding the reading ability of children with intellectual disabilities (ID) can help them improve their communication skill and cognition, but little is known about how home literacy environment (HLE) improves the reading ability of children with ID. The aim of the current study was to explore the mutual predictive relationship…

Executive functions (EF) have long been recognized as critical factors in accounting for individual differences in literacy development. However, their role in second language (L2) learning, particularly in non-alphabetic languages such as Chinese, has not been fully explored. This study endeavored to examine the role of EF in word reading among…

Children with autism often display discrepancies in their intellectual functioning, with nonverbal skills frequently being more developed than verbal. Compared to monolingual autistic children, however, much less is known about how bilingualism affects intelligence in autism. The current study examined the intelligence profiles of 146 bilingual…

Several studies have demonstrated that individual differences in processing speed fully mediate the association between age and intelligence, whereas the association between processing speed and intelligence cannot be explained by age differences. Because measures of processing speed reflect a plethora of cognitive and motivational processes, it…

Differentiation of intelligence refers to changes in the structure of intelligence that depend on individuals' level of general cognitive ability (ability differentiation hypothesis) or age (developmental differentiation hypothesis). The present article aimed to investigate ability differentiation, developmental differentiation, and their…

In the current study, we tested a network model of reading difficulty by using state-of-the-art psychological network analysis. Four hundred and fifty-three Chinese first-grade children (about 38% female, mean age = 7.00, SD = 0.41) were divided into good (n = 154), competent (n = 147), and struggling (n = 152) readers based on their scores of…

This study examined the identification frameworks, specific models, and assessment practices used by school psychologists to identify students with specific learning disabilities (SLD) in public schools in the United States. We surveyed school psychologist practitioners using an online survey, conducted a review of state regulations addressing…

This paper provides a meta-analytic update on the relationship between intelligence and divergent thinking (DT), as research on this topic has increased, and methods have diversified since Kim's meta-analysis in 2005. A three-level meta-analysis was used to analyze 849 correlation coefficients from 112 studies with an overall N = 34,610. The…

Background: Recent research suggested fluent processing as an explanation on why number sense contributes to simple arithmetic tasks--'Fluency hypothesis'. Aims: The current study investigates whether number sense contributes to such arithmetic tasks when other cognitive factors are controlled for (including those that mediate the link); and…

An enduring challenge in visual-spatial research has been to identify the factors contributing to individual differences in ability. This research investigated the overall, verbal, and nonverbal visual-spatial ability of 61 (34 boys) three- to five-year-olds (M[subscript age] = 57.3 months; SD = 7.9) and the following factors known to be related…

Intelligence tests and adaptive behavior scales measure vital aspects of the multidimensional nature of human functioning. Assessment of each is a required component in the diagnosis or identification of intellectual disability, and both are frequently used conjointly in the assessment and identification of other developmental disabilities. The…