School psychologists use intelligence and academic achievement test scores to understand individual differences in abilities that may be directed towards learning and the learning that has already occurred. To make ethical and effective decisions regarding individualized educational programs and interventions, test users must understand the…

Purpose: Researchers have previously shown that individual differences in measures of receptive language ability at age 12 are highly heritable. In the current study, the authors attempted to identify some of the genes responsible for the heritability of receptive language ability using a "genome-wide association" approach. Method: The…

Genetic and environmental correlations among 11 Wechsler Intelligence Scale for Children-Revised (WISC-R) subtests were estimated from a sample of 143 twin pairs using the methodology of multivariate behavioral genetics. Correlations due to within-pair environmental influences were generally small, whereas those due to shared environmental…