This study examined whether children's growth on measures of fluid (Raven Colored Progressive Matrices) and crystallized (reading and math achievement) intelligence was attributable to domain-specific or domain-general functions of working memory (WM). A sample of 290 elementary school children was tested on measures of intelligence across three…

Previous studies based on population cohorts born at least 35 years ago, have reported appreciable childhood cognitive deficits for twins. We compared longitudinal IQ scores from approximately 188,000 singletons and some 6000 twins who went to primary school in the Netherlands from 1994 to 2003. In addition, we used a family-based design in which…

Results from a quasi-experimental research design used with 578 10-year-old children showed considerable effects of schooling on all intelligence tests given, including tests of fluid intelligence, and indicated that schooling effects explained most of the intellectual progress made in 1 year at that age. (SLD)

Administered two intelligence batteries and a computer-assisted elementary cognitive test battery to 474 second-generation migrant and 747 majority-group students, aged 6 to 12 years, in the Netherlands. Findings suggest that performance differences between these groups are better predicted by a cultural complexity ("c") factor than by…

A 76-item test of intellect-related personality traits was developed and administered to 46 gifted 13 year olds, 51 undergraduates, and 53 seventh and eighth graders. Three component-based traits were obtained: intellectual absorption, apathy, and pleasure. These traits were found to be related to intellectual performance. (TJH)

Results from a battery of 17 diverse tests completed by 877 white and 855 black students in grades 3 through 8 support Spearman's hypothesis that the white-black difference in test performance is predominantly a general intelligence ("g") difference rather than a unitary developmental difference affecting all factors in test performance.…

Inspection time (IT) and Peabody Picture Vocabulary Test (PPVT) scores from 75 school children aged 6-13 years in 2001 were compared with the performances of 70 children aged 6-13 years who had attended the same primary school in 1981 ["J. Exp. Child Psychol." 40 (1985) 1.]. ITs for the 2001 sample were measured with the same four-field…

The predictive validity and utility of assessment procedures can be increased by adding predictors to the prediction supplied by general ability tests. Of Jensen's early work comes the suggestion of focusing on the cognitive ability short-term memory (STM), especially for low-"g" Black children. Meta-analysis convincingly shows high…

The hypothesis was investigated that conflicting evidence on Japanese intelligence has arisen because the Japanese have a distinctive profile of abilities. It was found that Japanese children do not differ from American children on general intelligence, score higher on the group perceptual factor, and lower on the group verbal factor. (Author/LMO)

Major visuospatial and verbal abilities were assessed for 197 10-year-olds in Hong Kong and 170 10-year-olds in the United Kingdom. The Hong Kong subjects resembled their Japanese counterparts in having high Searman's "g," exhibiting abstract reasoning ability, high spatial ability, high perceptual speed, and low word fluency. (SLD)

Intelligence tests were administered twice to 426 members of 93 transracial adoptive families, once when the adopted children's ages averaged 7 years and again when they averaged 17 years. Correlations suggest that influences on intellectual development in this sample of black and interracial adoptees reared in white families are similar to those…

Genetic and environmental etiologies of individual differences in tests of intelligence and school achievement were investigated in a study from the Colorado Adoption Project. A multivariate conditional path model was fitted to general cognitive ability and reading performance data from 119 adoptive and 120 nonadoptive families. (SLD)