Comparison of twins (40 identical and 23 fraternal) for mathematics deficits (MD), in which at least one member had a mathematics disability, found evidence for a significant genetic etiology. However, tests for the differential etiology of MD as a function of reading performance level were nonsignificant. (Author/DB)

This study examined 87 pedigrees of individuals with histories of preschool phonology disorders. Significantly more family members with dyslexia and learning disabilities, but not stuttering or hearing impairment, were found in pedigrees of individuals with phonology disorders than in pedigrees of nondisabled individuals. (Author/JDD)

Pedigree analysis of 12 young adults (9 of whom had learning disabilities) indicated that learning disability (LD) was strongly familial but that the type of disability (reading or math) was not directly inherited. Autoimmune disorders were significantly correlated with LD. In seven of the LD families, adults failed to overcome earlier reading and…

This study provides support for a potential subclinical marker in the executive function domain of siblings (n=18, ages 8-18) of autistic individuals, compared to learning-disabled controls. No group differences in theory-of-mind abilities were found. The need to develop more sensitive measures is discussed. (Author/JDD)

Follows 46 unselected children with various sex chromosome abnormalities using intellectual, language, and achievement testing. Notes that, although most children were not mentally retarded, most received special education help. Finds support for the inference that learning disorders were genetically mediated in this group. (RS)

Examined heritability of reading deficits in dyslexic subtypes. Found reading deficits were heritable in developmental phonological and surface dyslexics, with greater genetic contribution in the former. Findings suggest a partial independence in the development of cognitive processes involved in reading, and affirm accounts of surface dyslexia…

Word recognition data from identical and fraternal twins and siblings (N=172) indicated that the phonological coding deficit of children with reading disabilities was highly heritable. Orthographic coding was not significantly heritable. Poor readers with low IQs were superior to similar reading but average IQ readers in phonological coding.…

This article offers a historical overview of the neurological aspects of dyslexia (originally seen as related to aphasia) and a review of familial and genetic factors in developmental dyslexia. Psycholinguistic models of dyslexia as they relate to neurological concepts are presented and the evolution of successful remedial methods is summarized.…

This investigation examined whether articulation problems represent a more pervasive linguistic or cognitive disability and whether a genetic component exists, by following up a longitudinal articulation study of 394 normally developing children begun in 1960. A group of 24 individuals, aged 31-33, who had participated in the original study and…

This paper reviews the research on fragile X syndrome, the second most common cause of mental retardation related to chromosomal anomaly. It notes that far more males than females are affected by the fragile X syndrome, which typically results in craniofacial changes, delays in growth and development, speech/language difficulties, and cognitive…

The proceedings include 33 papers and two addresses on the psychopathology of mental development. The following six subject areas are considered: genetics and neurophysiology, socio-cultural and paranatal factors; epidemiology; behavior characteristics and learning; observational techniques and measurement of intelligence; and diagnosis and…