Upon hearing a novel label, listeners tend to assume that it refers to a novel, rather than a familiar object. While this disambiguation or mutual exclusivity (ME) effect has been robustly shown across development, it is unclear what it involves. Do listeners use their pragmatic and lexical knowledge to exclude the familiar object and thus select…

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…

Emerging cognitive control supports increasingly efficient goal-directed behaviors. With age, children are increasingly expected to decide autonomously and with little external aid which goals to attain. However, little is known about how children engage cognitive control in such a self-directed fashion. The present study examined self-directed…

Emerging evidence suggests interventions can improve childhood self-regulation. One intervention approach that has shown promise is Taekwondo martial arts instruction, though little is known about its acceptability among stakeholders or its mechanisms of effect. We extend evidence on Taekwondo interventions in three ways: (1) testing the efficacy…

Children tell prosocial lies from the age of three years onward, but little is known about for whom they are inclined to lie. This preregistered study examined children's (N = 138, 9-12 years) prosocial lying behavior toward minimal in-group and out-group peers. Additionally, children evaluated vignettes in which an in-group peer told a prosocial…

Conflict adaptation is key in how children self-regulate and assert cognitive control in a given situation compared with a previous experience. In the current study, we analyzed event-related potentials (ERPs) to identify age-related differences in conflict adaptation. Participants of different ages (5-year-old children, 10-year-old children, and…

Given the centrality of prosociality in everyday social functioning, understanding the factors and mechanisms underlying the origins of prosocial development is of critical importance. This experiment investigated whether experience with reciprocal object exchanges can drive the developmental onset of sharing behavior. Seven-month-old infants took…

This study tests the hypothesis that adolescents with romantic partners are less similar to their friends on rates of alcohol abuse than adolescents without romantic partners. Participants (662 girls, 574 boys) ranging in age from 12 to 19 years nominated friends and romantic partners, and completed a measure of alcohol abuse. In hierarchical…

We investigated the role of sociocultural (between-groups) and individual (within-group) factors on the development of preschoolers' resource-allocation preferences. We tested claims of the "joint impact hypothesis" of social values development that social-emotional understanding skills would predict the transition from simpler…

The present longitudinal study addressed the ongoing debate regarding the benefits and risks of infant-parent cosleeping by examining associations between sleep arrangement patterns across the first year of life and infant and parent sleep, marital and family functioning, and quality of mothers' behavior with infants at bedtime. Patterns of infant…

Controversy continues to surround parenting by lesbian and gay (LG) adults and outcomes for their children. As sexual minority parents increasingly adopt children, longitudinal research about child development, parenting, and family relationships is crucial for informing such debates. In the psychological literature, family systems theory contends…

This study used data from 356 children, their mothers, teachers, and peers to examine the longitudinal and dynamic associations among 3 dimensions of social competence derived from Hinde's (1987) framework of social complexity: social skills, peer group acceptance, and friendship quality. Direct and indirect associations among each discrete…

A robust finding across research on early childhood educational interventions is that the treatment effect diminishes over time, with children not receiving the intervention eventually catching up to children who did. One popular explanation for fadeout of early mathematics interventions is that elementary school teachers may not teach the kind of…

Reviews of behavioral genetic studies note that "control" aspects of parenting yield low estimates of heritability, while "affective" aspects (parental feelings) yield moderate estimates. Research to date has not specifically considered whether positive and negative aspects of parenting--for both feelings and control--may…

Developmental studies on heuristics and biases have reported controversial findings suggesting that children sometimes reason more logically than do adults. We addressed the controversy by testing the impact of children's knowledge of the heuristic stereotypes that are typically cued in these studies. Five-year-old preschoolers and 8-year-old…