This study investigated the systematic rise in cognitive ability scores over generations, known as the "Flynn Effect," across middle childhood and early adolescence (7-15 years; 291 monozygotic pairs, 298 dizygotic pairs; 89% White). Leveraging the unique structure of the Louisville Twin Study (longitudinal data collected continuously…

Intellectual performance is highly heritable and robustly predicts lifelong health and success but the earliest manifestations of genetic effects on this asset are not well understood. This study examined whether early executive function (EF) or verbal performance mediate genetic influences on subsequent intellectual performance, in 561 U.S.-based…

This paper estimates the acute effect of community-level homicides on early childhood language development and explores the moderating role of maternal efficacy and satisfaction in Chile. It uses data from the 2017 wave of the Early Childhood Longitudinal Survey of Chilean Children (N = 1194, M[subscript age]: 52.8 months, 52% girls). Children in…

The Wechsler Preschool and Primary Scale of Intelligence, 4th ed. includes two measures of working memory normed on children 2;6-7;7. The present analyses of the typically developing children (N = 1,591, 812 female, 779 male, with an ethnic distribution approximating the United States) provide new, theoretically important information about these…

The study investigated whether age at attainment of 20 developmental milestones within the areas of language, walking, eating, dressing, social interaction, and toilet training was associated with adult intelligence. Mothers of 821 children of the Copenhagen Perinatal Cohort recorded 20 developmental milestones at a 3-year examination, and all…

We compared the extent to which the long-term influence of family socioeconomic status (SES) on children's school performance from age 7 through 16 years was mediated by their preschool verbal and nonverbal ability. In 661 British children, who completed 17 researcher-administered ability tests at age 4.5 years, SES correlated more strongly with…

This study investigates the relationship between early maternal employment history and children's vocabulary and inductive reasoning ability at age 5, drawing on longitudinal information on 2,200 children from the Growing Up in Scotland data. Prior research rarely addresses dynamics in maternal employment and the methodological ramifications of…

This study explores children's early academic and self-regulatory skills as potential pathways through which a preschool enrichment program--the Chicago School Readiness Project (CSRP)--may contribute to low-income children's long-term outcomes (N = 466; M[subscript age] at baseline = 4.10 years). We find that CSRP's impact on high school grades…

Cognitive impairment is common among children born very preterm (VPT), yet little is known about how this risk changes over time. To examine this issue, a regional cohort of 110 VPT (= 32 weeks gestation) and 113 full-term (FT) born children was prospectively assessed at ages 4, 6, 9, and 12 years using the Wechsler Preschool and Primary Scale of…

This study examined the relation of 3-year core information-processing abilities to lexical growth and development. The core abilities covered four domains--memory, representational competence (cross-modal transfer), processing speed, and attention. Lexical proficiency was assessed at 3 and 13 years with the Peabody Picture Vocabulary Test (PPVT)…

The purpose of this study was to empirically examine the dimensionality of language ability for young children (4-8 years) from prekindergarten to third grade (n = 915), theorizing that measures of vocabulary and grammar ability will represent a unitary trait across these ages, and to determine whether discourse skills represent an additional…

This study uses a national sample of 1,215 children, ages 6-17, who spent some time in formal kinship or nonrelative foster care to identify the effect of placement type on academic achievement, behavior, and health. Several identification strategies are used to reduce selection bias, including ordinary least squares, change score models,…

The analysis of WISC scores for 314 school-age twins and 221 of their siblings revealed high concordance of full-scale and verbal IQ for monozygotic twins. The IQ concordance for dizygotic twins, twin-sibling pairs, and sibling pairs were comparable to each other but significantly lower than that for monozygotic twins. (Author/JMB)

No reliable IQ differences were found when the Stanford-Binet was administered to 100 4-year-old Negro children under two conditions of language (Standard English and Negro dialect) and two conditions of reinforcement (praise and candy). (Author/WY)