During adolescence, increases in pubertal hormones lead to reproductive maturity as well as changes in cognitive development. Yet, little is known about how to best characterize interindividual differences in hormone concentrations. The goal of the current study was to examine the antecedents and consequences of membership in empirically derived…

This study explores the cognitive development of children born to adolescent mothers within South Africa compared to existing reference data, and explores development by child age bands to examine relative levels of development. Cross-sectional analyses present data from 954 adolescents (10-19 years) and their first-born children (0-68 months).…

The present studies (N = 159) investigated children's and adults' preferences for label and property conjunctions for cross-classifiable toys. In Study 1, 4-year-olds, 5-year-olds, and adults participated in a labelling and property attribution task involving experimental toys that belong to two categories and control toys that belong to only one…

Attention allocation in word learning may vary developmentally based on the novelty of the object. It has been suggested that children differentially learn verbs based on the novelty of the agent, but adults do not because they automatically infer the object's category and thus treat it like a familiar object. The current research examined…

This research examined children's performance on second-order false belief tasks as a function of the content area for the belief and the method of assessing understanding. A total of 70 kindergarten and first-grade children responded to four second-order stories. On two stories, the task was to judge a belief about a belief, and on two, the…

This study examined the contribution of child temperament, parenting, and their interaction on inhibitory control development in a sample of maltreated and non-maltreated preschool children. One hundred and eighteen mother-child dyads were drawn from predominantly low-income, rural communities. Dyads participated in a laboratory session in which…

Children's ability to distinguish between enjoyment and non-enjoyment smiles was investigated by presenting participants with short video excerpts of smiles. Enjoyment smiles differed from non-enjoyment smiles by greater symmetry and by appearance changes produced in the eye region by the Cheek Raiser action. The results indicate that 6- and…

This study examined the prevalence and determinants of spanking of children at 3?years of age and the associations between spanking and externalizing behaviour and receptive verbal ability at age 5?years. Overall, we find maternal spanking rates of 55.2% and paternal rates of 43.2% at age 3?years. Mothers facing greater stress and those who…

This study used the Alberta Infant Motor Scale (AIMS) with the aim of characterizing motor acquisition rate in 70 healthy 0-6-month-old Brazilian infants, as well as comparing both emergence (initial age) and establishment (final age) of each skill between the study sample and the AIMS normative data. New motor skills were continuously acquired…

As part of a longitudinal investigation of infants at familial risk for attention-deficit hyperactivity disorder (ADHD), mothers and fathers independently completed temperament ratings on their infants. In this paper, we examine the 7-, 12-, and 25-month temperament of 58 boys, 36 of whom were considered at familial risk for ADHD and 22 of whom…