In many decision situations, individuals must actively search information before they can make a satisfying choice. In such instances, individuals must be aware of the fact that not all information may be equally relevant for the choice at hand--thus, individuals should weight information by its respective relevance. We compared children's and…

Longitudinal data from a large sample of twins participating in the Netherlands Twin Register (n = 42,827, age range 3-16) were analyzed to investigate the genetic and environmental contributions to childhood aggression. Genetic auto-regressive (simplex) models were used to assess whether the same genes are involved or whether new genes come into…

The present study compared the course of parent-report and actigraphy-derived sleep profiles over a 1-year period, in school-age children with autism spectrum disorder and typically developing children. The Children's Sleep Habits Questionnaire and 14 nights of actigraphy were used to assess sleep profiles. Parents also completed the Spence…

Much research has investigated how children relate to norms taught to them by adult authorities. Very few studies have investigated norms that arise out of children's own peer interactions. In two studies, we investigated how 5- and 7-year-old children teach, enforce, and understand rules that they either created themselves or were taught by an…

How do toddlers learn the names of geometric forms? Previous work suggests that preschoolers have fragmentary knowledge and that defining properties are not understood until well into elementary school. The current study investigated when children first begin to understand shape names and how they apply those labels to unusual instances. We tested…

Autism spectrum disorder (ASD) and autism-like traits are associated with deficits in face memory ability, although it is not yet clear whether this deficit reflects a specific aspect of the ASD/autism-like phenotype. We addressed this issue using a neurotypical sample of adolescent twins (N[subscript complete pairs] = 782) drawn from the Twins…

How do toddlers learn the names of geometric forms? Previous work suggests that preschoolers have fragmentary knowledge and that defining properties are not understood until well into elementary school. The current study investigated when children first begin to understand shape names and how they apply those labels to unusual instances. We tested…

The vocabulary size and composition of one group of full-term and three groups of low risk preterm children with different gestational ages (GA) were longitudinally compared at 10, 22 and 30 months of age. Expressive vocabulary development was assessed through the CDI. Cognitive development was also assessed at 22 months (Batelle Developmental…

The teaching of historical time is an important aspect in elementary school curricula. This study focuses on the effects of a curriculum intervention with "Timewise," a teaching approach developed to improve students' understanding of historical time using timelines as a basis with which students can develop their understanding of…

Deaf and hard of hearing school-aged children are at risk for delayed development of emotion understanding; however, little is known about this during the preschool years. We compared the level of emotion understanding in a group of 35 4-5-year-old children who use hearing aids to that of 130 children with typical hearing. Moreover, we…

Fragmented sleep is common in infancy. Although night awakening is known to decrease with age, in some infants night awakening is more persistent and continues into older ages. However, the influence of fragmented sleep on development is poorly known. In the present study, the longitudinal relationship between fragmented sleep and psychomotor…

This study looked at the relationship between participation in a structured sports program and gross-motor-skills development in children aged 3 to 6 years. Twenty-seven children participated in the study, with 16 children receiving an eight-week sports program intervention. Children were assessed at pre- and postintervention using a modified…

Given the dependent nature of parent-infant interactions necessary for language development, it is important to understand how context may influence these interactions. This study examines how contextual variables influence communicative, cognitive and social measures of parent-infant interactions. Specifically, how do feedback toys and…

Saccade latency is widely used across infant psychology to investigate infants' understanding of events. Interpreting particular latency values requires knowledge of standard saccadic RTs, but there is no consensus as to typical values. This study provides standard estimates of infants' (n = 194, ages 9 to 15 months) saccadic RTs under a range of…

Play is essential for growth and learning during early childhood. However, the current focus on academics in preschool education has resulted in less emphasis placed on play as a learning tool. In the current study, parents' value of play was investigated. Parent gender, child gender, and child age were examined as potential influences on parents'…