Background: Parenting factors may be important to the development of attributional style in adolescence, which in turn relates to depression symptoms. These relationships have mainly been considered in terms of social risk mechanisms, and little is known about the role of genetic influences. Method: Self-reported measures of attributional style,…

Background: Individuals with early warning signs of life-long psychopathy, callous-unemotional traits (CU) and high levels of antisocial behaviour (AB) can be identified in childhood. We report here the first twin study of high levels of psychopathic tendencies in young children. Methods: At the end of the first school year, teachers provided…

Multivariate genetic analysis was used to examine the genetic and environmental aetiology of the interrelationships of diverse linguistic skills. This study used data from a large sample of 4 1/2-year-old twins who were tested on measures assessing articulation, phonology, grammar, vocabulary, and verbal memory. Phenotypic analysis suggested two…

This study of 4,274 pairs of 4-year-old twins from the Twins Early Development Study explored the magnitude of genetic and environmental effects on low expressive vocabulary skill, both as a function of general cognitive ability and as a function of the severity of expressive vocabulary impairment. Assessments were conducted through parent report…

A study investigated whether young children use sentence accent to mark new information as systematically as they have been shown to handle contrastive stress within naturally-occurring discourse. Data were drawn from the spontaneous conversations of a boy-and-girl twin pair with adults. The twins' speech was coded in carefully-defined categories…

Used the Sibling Inventory of Differential Experience with 396 adolescent and young adult children to determine the extent to which genetic differences between siblings or sibling differences in family constellation variables were responsible for differential experiences. (HOD)

Parent-based assessments of vocabulary, grammar, nonverbal ability, and use of language to refer to past and future were obtained for 8,386 twins at age 2. Of the children who had early language delay, 44.1% had persisting language difficulties at 3 years and 40.2% had persisting language difficulties at 4 years. (Contains references.) (CR)

Various types of recent research studies using data on twins, from longitudinal surveys of different cohorts, and cross-section data on earnings, all suggest that the payoff to schooling in the United States is high and especially high for investment in college. Discusses why this is so. (SLD)

To study the social-emotional development of triplets, 23 sets of triplets, 23 sets of twins, and 23 singleton infants (N=138) were followed from birth to 2 years. Maternal depression and social support were assessed in the postpartum period, mother-infant and father-infant interaction and the home environment were observed at 3 months, a…

Parental divorce is associated with problematic offspring adjustment, but the relation may be due to shared genetic or environmental factors. One way to test for these confounds is to study offspring of twins discordant for divorce. The current analyses used this design to separate the mechanisms responsible for the association between parental…

Objective: We investigated the role of genetic and environmental factors in the developmental association among symptoms of eating disorders, depression, and anxiety syndromes in 8-13-year-old and 14-17-year-old twin girls. Methods: Multivariate genetic models were fitted to child-reported longitudinal symptom data gathered from clinical interview…

Background: Childhood psychopathology is associated with both high and low levels of prosocial behaviour. It has been proposed that the development of prosocial behaviour shows emerging and consolidating individual differences as children grow older. The influences on these individual differences have not previously been examined in children and…

Objective: The purpose of this study was to assess heritability of activity, attention, and impulsivity by comparing young monozygotic (MZ) twins with dizygotic (DZ) twins using objective measures. Method: The OPTAx test is an infrared motion analysis to record the movement pattern during a continuous performance test. Seventeen MZ and 12 same…

The authors apply descriptive and sequential analyses to a mother's distancing strategies toward her 3-year-old twin sons in puzzle assembly and book reading tasks. One boy had normal hearing and the other a mild hearing loss (threshold: 30 dB). The results show that the mother used more distancing behaviors with the son with a hearing loss, and…

Objective: To investigate children selected from a community sample for showing extreme autistic-like traits and to assess the degree to which these individual traits--social impairments (SIs), communication impairments (CIs), and restricted repetitive behaviors and interests (RRBIs)--are caused by genes and environments, whether all of them are…