Differentiation hypotheses concern changes in the structural organization of cognitive abilities that depend on the level of general intelligence (ability differentiation) or age (developmental differentiation). Part 1 of this article presents a review of the literature on ability and developmental differentiation effects in children, revealing…

The architecture of sleep undergoes distinct changes during childhood and early adolescence. Slow wave sleep is involved in memory processing and may support active consolidation of newly encoded representations to support the formation of abstracted "gist" memories. Here, we examined sleep and overnight memory formation in German school…

Few studies have investigated associations of milestone development in early childhood with intelligence in adulthood in typically developing children. The current study is an extension of 2 previous studies on smaller samples and investigated associations of age at attainment of 32 developmental milestones attained between 0 and 3 years of age…

HIV-exposed uninfected (HEU) children during the preschool and early school ages may be at-risk for neurodevelopmental challenges due to in utero and perinatal exposure to HIV and/or antiretroviral (ARV) medications. HEU children and HIV-unexposed uninfected (HUU) children from the community were recruited and tested at 3 to 4 and 5 to 6 years of…

As a spoken word unfolds over time, similar sounding words ("cap" and "cat") compete until one word "wins". Lexical competition becomes more efficient from infancy through adolescence. We examined one potential mechanism underlying this development: lexical inhibition, by which activated candidates suppress…

Some previous reviews conclude that breastfeeding is not significantly associated with increased intelligence in children once mother's IQ is statistically controlled. The conclusion may potentially have both theoretical and methodological problems. The National Child Development Study allows the examination of the effect of breastfeeding on…

Guided by evolutionary-developmental models, this study tested the hypothesis that children's exposure to parental relationship instability, defined by initiation and dissolution of caregiver intimate relationships, has both costs in cognitive impairments and benefits in enhanced learning skills. Participants included 243 mothers and their…

Given the importance of writing for academic achievement, this study aimed to understand how early oral language contributes to later writing skills. The first objective was to determine if preschool language skills were associated with high school writing, and if so, whether they contributed directly or indirectly through school age language. The…

Throughout childhood and adolescence, humans experience marked changes in cortical structure and cognitive ability. Cortical thickness and surface area, in particular, have been associated with cognitive ability. Here we ask the question: What are the time-related associations between cognitive changes and cortical structure maturation.…

This study examines the extent to which iron deficiency in infancy contributes to adverse neurocognitive and educational outcomes in young adulthood directly and indirectly, through its influence on verbal cognition and attention problems in childhood. Young adults (N = 1,000, M age = 21.3 years, 52% female; of Spanish or indigenous descent) from…

To benefit from the exploration of their bodies and their physical and social environments, infants need to detect sensorimotor contingencies linking their actions to sensory feedback. This ability, which seems to be present in babies from birth and even in utero, has been widely used by researchers in their study of early development. However, a…

Decision-making impairments during emerging adulthood confer risk for challenges in social and occupational roles and may increase the odds of developing health problems. Childhood maltreatment is related to maladaptation in cognitive and affective domains (e.g., executive functioning, emotion regulation) implicated in the development of…

Young children removed from institutions and placed into foster care or adoptive homes have been shown to experience significant gains in IQ relative to children who remain in institutions. Less is known about the long-term impact of severe early deprivation on development in late childhood. Data are presented from a follow-up of children at 12…

Proper segmentation of auditory streams is essential for understanding music. Many cues, including meter, melodic contour, and harmony, influence adults' perception of musical phrase boundaries. To date, no studies have examined young children's musical grouping in a production task. We used a musical self-pacing method to investigate (1) whether…

Understanding the role of negative emotionality in the development of executive functioning (EF) and language skills can help identify developmental windows that may provide promising opportunities for intervention. In addition, because EF and language skills are, in part, genetically influenced, intergenerational transmission patterns are…