Background: Empirical evidence demonstrates that conduct disorder (CD) symptoms tend to cluster into covert and overt domains. We hypothesized that overt and covert CD symptoms may be distinct constructs with distinct risk factors. An important risk factor for CD is maternal smoking during pregnancy. We further investigated this association,…

Background: We investigated the aetiology of language impairment in 579 four-year-old twins with low language performance and their co-twins, members of 160 MZ twin pairs, 131 same-sex DZ pairs and 102 opposite-sex DZ pairs. Methods: Language impairment in 4-year-olds was defined by scores below the 15th percentile on a general factor derived from…

Drawing upon self-categorization theory, we predicted that the content of children's stereotypes concerning the gender in-group would be contextually variable. Two studies are reported, each looking at five-, seven-, and 10-year-old children's stereotypes of the gender in-group in two different contexts. Study 1 examined judgements of the…

This paper uses internationally comparable household data sets (Demographic and Health Surveys) to investigate how gender and wealth interact to generate within-country inequalities in educational enrollment and attainment. The paper highlights that girls are at a great educational disadvantage in particular regions: South Asia and North, Western,…

Several methods have been developed, presented, and discussed at recent ASEE and EDGD conferences on the topic of computer-based multiview drawing instruction. While small-scale and localized testing of these instruments and methods has been undertaken, no larger-scale or multi-location experiments have been attempted. This paper describes an…

This case study describes the development and field-testing of a research-based scoring rubric for analyzing elementary students' schoolyard habitat drawings. To justify schoolyard learning experiences in U.S. schools, teachers, program evaluators, and others need valid, reliable, and objective assessment tools for determining if, and how, these…

In the present study, a systematic comparison of sex differences for several tests of spatial memory was conducted. Clear evidence for more accurate male performance was obtained for precise metric positional information in a wayfinding task and in an object location memory task. In contrast, no sex difference characterized topological information…

Sex and sexual orientation related differences in processing of happy and sad facial emotions were examined using an experimental facial emotion recognition paradigm with a large sample (N=240). Analysis of covariance (controlling for age and IQ) revealed that women (irrespective of sexual orientation) had faster reaction times than men for…

A semi-structured observational study investigated gender differences in delivered and received relational, physical, verbal, and nonverbal aggression in a young preschool sample (N=60). Findings revealed that gender differences in subtypes of aggression may be apparent as early as 3 years of age. Specifically, girls were found to deliver and…

In an effort to minimize the harmful effects of violent TV, a yearlong intervention was undertaken with children in Grades 1 through 3 (N = 177). The classroom-based intervention consisted of 31 brief lessons that emphasized the many ways in which television distorts violence. As hypothesized, the intervention resulted in a reduction in children's…

The main goal of this study was to examine possible socioeconomic status (SES) differences in 4- and 5-year-old children's informal mathematical knowledge. One hundred and two children, 32 from lower, 39 from middle, and 31 from upper SES families participated in the study. Each participant was given a clinical interview involving several addition…

This article reports two exploratory studies testing a model guided by a social interactional perspective, positing an inverse relation between the quality of parent-child interactions and adolescent problem behaviors. It addresses mixed findings in the literature related to gender differences. Study 1 uses cross-sectional survey data from…

The study assessed views of teachers, pupils and their guardians on left-hand preference. Seventy-five percent of the responders indicated that the left hand should not be preferred for habitual activities and 87.6% of them indicated that left-handers should be forced to change the hand. Gender had significant effect on the view on left hand…

An experiment was devised to test the empathising-systemising (E-S) theory of autism. Three groups of participants took part in the study: males with Asperger Syndrome (AS) (n = 18), males without AS, (n = 44) and females from the general population (n = 45). Each participant completed two tasks: one that involved empathising and another that…

Previous studies have suggested that among affected sib pairs with autism there is an increase in the frequency of twins over what would be expected in comparison to the prevalence of twins in the general population. In this study we sought to determine whether "sub-threshold" autistic traits were more pronounced in twins than in non-twins. The…