Individual differences in music traits are heritable and correlated with the development of cognitive and communication skills, but little is known about whether diverse modes of music engagement (e.g., playing instruments vs. singing) reflect similar underlying genetic/environmental influences. Moreover, the biological etiology underlying the…

Atypical sensory processing is prevalent across neurodevelopmental conditions and a key diagnostic criterion of autism spectrum disorder. It may have cascading effects on the development of adaptive functions. However, its unique contribution to adaptive functioning and the genetic/environmental influences on this link are unclear. In a clinically…

The home literacy environment is a well-established predictor of children's language and literacy development. We investigated whether formal, informal, and indirect measures of the home literacy environment predict children's reading and language skills once maternal language abilities are taken into account. Data come from a longitudinal study…

Background: Twin studies using both clinical and population-based samples suggest that the frequent co-occurrence of attention deficit hyperactivity disorder (ADHD) and reading ability/disability (RD) is largely driven by shared genetic influences. While both disorders are associated with lower IQ, recent twin data suggest that the shared genetic…

The ranking of Wechsler subtests in terms of their "g" loadings is equivalent to ranking them in terms of the cognitive complexity of the tasks measured. Lower performing groups do not always fall behind higher performing groups the more complex the task. But that is the general rule, no matter whether the cause of the lower performance…

The contribution of genetic factors to the memory is widely acknowledged. Research suggests that these factors include genes involved in the dopaminergic pathway, as well as the genes for brain-derived neurotrophic factor (BDNF) and methylenetetrahydrofolate reductase (MTHFR). The activity of the products of these genes is affected by single…

Background: Childhood onset schizophrenia (COS) is a rare disorder. Comparative data on the effect of differential age of onset on clinical profile in schizophrenia are very few. Method: Subjects with COS (n = 15), adolescence onset schizophrenia (AdOS, n = 20) and adulthood onset schizophrenia (AOS, n = 20) were compared on socio-demographic,…

The effects of family background on adolescents' IQ, aptitude, and school achievement test scores challenge some of the usual beliefs about the fairness of achievement rather than IQ tests, and the role of genetic differences among individuals and social class groups in academic achievements. Subjects included 115 adoptive families with adolescent…

Correlations on subscales of Wechsler intelligence quotient tests and the Revised Beta Examination were obtained for biologically related and unrelated individuals in 181 adoptive families in the Texas Adoption Project. Generally higher correlations for biologically related individuals support the importance of genetic influence in intellectual…

We report on a prospective longitudinal research programme exploring the connection between language acquisition deficits and dyslexia. The language development profile of children at-risk for dyslexia is compared to that of age-matched controls as well as of children who have been diagnosed with specific language impairment (SLI). The experiments…

Prison inmates (N=565) classified as underachievers or adequate readers were administered the Wechsler Adult Intelligence Scale-Revised. Analysis of recategorized WAIS-R scores suggested that, as a group, the underachieving readers exhibited a pattern different from that of genetic dyslexic Ss and different from that of reading and learning…

Background: Prader-Willi syndrome (PWS) is a rare genetic disorder characterised by developmental abnormalities leading to somatic and psychological symptoms. These include dysmorphic features, impaired growth and sexual maturation, hyperphagia, intellectual delay, learning disabilities and maladaptive behaviours. PWS is caused by a lack of…

Introduction: The aim of the present study was to determine whether individuals with Prader--Willi syndrome (PWS) have impaired global executive functioning and whether this deficit is linked with intellectual disability. Another objective focussed on the variability in performance of intellectual quotient (IQ) and executive functions (EF)…

Understanding the role of negative emotionality in the development of executive functioning (EF) and language skills can help identify developmental windows that may provide promising opportunities for intervention. In addition, because EF and language skills are, in part, genetically influenced, intergenerational transmission patterns are…

Recent research has established a connection between children's fine motor skills and their academic performance. Previous research has focused on fine motor skills measured prior to elementary school, while the present sample included children ages 5-18 years old, making it possible to examine whether this link remains relevant throughout…