Background: In this study several aspects of attention were studied in 237 nearly 6-year-old twin pairs. Specifically, the ability to sustain attention and inhibition were investigated using a computerized test battery (Amsterdam Neuropsychological Tasks). Furthermore, the Teacher's Report Form (TRF) was filled out by the teacher of the child and…

Objective: To test for gene-environment interaction with depressive symptoms and family conflict. Specifically, to first examine whether the influence of family conflict in predicting depressive symptoms is increased in individuals at genetic risk of depression. Second, to test whether the genetic component of variance in depressive symptoms…

This longitudinal study investigated hereditary and environmental influences on life situation, self-reported health, and coping ability at mid-life in relation to background factors collected during adolescence. A nationally representative Swedish sample comprised of monozygotic (MZ) and dizygotic (DZ) twins; a control group of singletons was…

This book, for children aged 7 and up, is designed to teach younger children about human biology and healthy sexuality, allowing parents and teachers to answer children's questions. Comic book style, full-color artwork illustrates the age-appropriate text and reflects an elementary school child's interest in biology and how things work. The book…

Background: Socioeconomic status is often assumed to be of importance for the development of antisocial behavior, yet it explains only a fraction of the variance. One explanation for this paradox could be that socioeconomic status moderates the influence of genetic and environmental effects on antisocial behavior. Method: TCHAD is a Swedish…

Background: Five DNA markers (single-nucleotide polymorphisms, SNPs) have recently been found to be associated with general cognitive ability "g") in a sample of 7414 7-year-old twins. These children have also been studied at 2, 3, 4, and 7 years of age on measures of cognitive and language development and behaviour problems; family environment…

This longitudinal monozygotic (MZ) twin differences study explored associations between birthweight and early family environment and teacher-rated behaviour problems and academic achievement at age 7. MZ differences in anxiety, hyperactivity, conduct problems, peer problems and academic achievement correlated significantly with MZ differences in…

Purpose: This study examined (a) the extent of genetic and environmental influences on children's articulation and language difficulties and (b) the phenotypic associations between such difficulties and direct assessments of reading-related skills during early school-age years. Method: Behavioral genetic analyses focused on parent-report data…

A case study of a pair of extremely deprived twin boys focuses on their verbal communication. Talkativeness alone was not regarded as a measure of intelligence, but attention was paid to the less talkative twin's greater use of imaginative speech. Speculations are made on the evolutionary role of creative speech. (IS)

The Twins and Siblings study is available in a machine-readable data file that is part of the High School and Beyond (HSB) Class of 1980 Survey, administered in 1980 to a national sample of over 30,000 sophomores and 28,000 seniors from 1,015 high schools throughout the United States. This file contains data from 616 sampled twins and triplets…

Directed to parents, the text discusses normal and delayed speech development and considers the causes of delay. Suggestions are given for helping deaf, emotionally disturbed, brain damaged, and physically handicapped children. Additional suggestions are provided for parents of twins, of stutterers, and of mongoloid or multiply handicapped…

Conceived around the notion that there are multiple sources of influence on children's development, this volume describes when, where, and how parenting matters and the major antecedents and moderators of effective parenting. The chapters of the volume are as follows: (1) "Beyond the Nurture Assumption: Testing Hypotheses about the Child's…

Background: It is not known if the prevalence of parental psychiatric disorders is higher in stepfather than intact families, or if parental alcoholism is differentially associated with risk for conduct disorder (CD) symptoms in stepfather families versus intact families. Method: The sample comprised 839 girls and 741 boys from 792 intact families…