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…

Phonological difficulties characterize children with developmental dyslexia across languages, but whether impaired auditory processing underlies these phonological difficulties is debated. Here the causal question is addressed by exploring whether individual differences in sensory processing predict the development of phonological awareness in 86…

Experts claim that individual differences in children's formal understanding of mathematical equivalence have consequences for mathematics achievement; however, evidence is lacking. A prospective, longitudinal study was conducted with a diverse sample of 112 children from a midsized city in the Midwestern United States (M[subscript age] [second…

Little research has considered whether prenatal experience contributes to executive function (EF) development above and beyond postnatal experience. This study tests direct, mediated, and moderated associations between prenatal risk factors and preschool EF and IQ in a longitudinal sample of 1,292 children from the Family Life Project. A composite…

This research examined how motivation (perceived control, intrinsic motivation, and extrinsic motivation), cognitive learning strategies (deep and surface strategies), and intelligence jointly predict long-term growth in students' mathematics achievement over 5 years. Using longitudinal data from six annual waves (Grades 5 through 10;…

The authors examined 284 maltreated and nonmaltreated children's (6- to 12-year-olds) ability to inhibit true and false memories for neutral and emotional information using the Deese/Roediger-McDermott (DRM) paradigm. Children studied either emotional or neutral DRM lists in a control condition or were given directed-remembering or…

Academic achievement and cognitive ability have been shown to predict later age at first sexual intercourse. Using a sample of 536 same-sex twin pairs who were followed longitudinally from adolescence to early adulthood, this study tested whether relations between intelligence, academic achievement, and age at first sex were due to unmeasured…

While father absence due to divorce, desertion, or separation had the most negative influence in the initial 2 years of the child's life for boys and girls, father absence due to death was the most detrimental when it occurred in the 6 - 9 period of the boy's life. (Author)

Intelligence test scores were obtained from parents and children in 300 adoptive families and compared with similar data available from the children's biological mothers. Results support the hypothesis that genetic variability is an important influence in the development of individual differences in intelligence. (Author/RH)

Examined the relative role of parent-child relationships, family stress, and disease factors in predicting behavior problems in children with epilepsy. Found that children's self-reliance correlated with parent-reported behavior problems, whereas expression of affect related to teacher-reported problems. Overall, parent-child relationship factors…

This study explored the relationships among children's performance on a simplified version of Kagan's Matching Familiar Figures (MFF) Test of conceptual tempo, their IQ, their performance on several measures of self-regulatory behavior, and their general activity level. Subjects were 55 preschool boys and girls. (Author/JMB)

Reexamines data from a study by Bayley and Schaefer and argues that no significant sex difference was demonstrated in their study. Points out that the male and female samples differed significantly with respect to both level of mother's education and children's IQ variance. (Author/JMB)

The IQ performance of children who experienced the birth of a younger sibling was found to drop 10 points during the next two years for singleton children and 5.8 points for last-born children from families of comparable size. The study controlled for sex, family size, age at assessment, and IQ before the birth of the sibling. (Author/RH)

Analyzed genetic and environmental contributions to intellectual change in 258 adopted and 93 biological children of 3-14 years. The effect of genes and family environment was significant at the time of the first measurement, but only genes made an additional contribution between the first and the second. (RJC)

Significant correlations were obtained between Home Observation for Measurement of the Environment (HOME) Inventory scores and two clusters of items from the Bayley Scales of Infant Development: goal directedness and language use. HOME assessments were made when children were 6 and 12 months old; the Bayley was administered at 12 months.…