General cognitive ability ("g") does not explain sex differences in academic test performance by the end of compulsory education. Instead, individual differences in specific reasoning abilities, after removing the effects of "g," may contribute to the observed gender gaps. Associations between general or specific cognitive…

This study explores whether or not intelligence tests' scores predict individual differences in scholastic achievement irrespective of SES factors such parents' income and education. The variables of interest are analyzed considering three independent samples of participants comprising a total of 641 children. The participants belonged to a…

The roles of attention in reaction time and in relationships among reaction time, intelligence, and achievement were studied in seventh graders. Reaction time measures were correlated with attention and perceptual speed as well as general intelligence and achievement measures. Implications for current theories linking reaction time and…

Reaction time and movement time were negatively and moderately-to-strongly correlated with Ravens matrices performance and with reading comprehension and performance on the California Test of Basic Skills for 20 ninth-grade girls. Weaker relationships were found for mathematics and English grades, although the direction was consistently negative.…

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)