There is renewed interest in person-centered approaches to understanding the structure of temperament. However, questions concerning temperament types are not frequently framed in a developmental context, especially during infancy. In addition, the most common person-centered techniques, cluster analysis (CA) and latent profile analysis (LPA),…

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…

Based on Marcia's theory, many researchers consider exploration and commitment as the main processes in identity development. Although some identity theorists have hypothesized that emotional experience may also be an important part of the mechanisms of identity development, empirical research to investigate this claim has been lagging behind. In…

The first months after becoming a new parent are a unique and important period in human development. Despite substantial research on the many social and biological changes that occur during the first months of parenthood, little is known about changes in mothers' attachment. The present study examines developmental stability and change in…

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 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…

Vagal tone is widely believed to be an important physiological aspect of emotion regulation and associated positive behaviors. However, there is inconsistent evidence for relations between children's baseline vagal tone and their helpful or prosocial responses to others (Hastings & Miller, 2014). Recent work in adults suggests a quadratic…

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…

Maltreating mothers often struggle to respond sensitively to their children's distress. Examining psychophysiological processing of own child cues may offer insight into neurobiological mechanisms that promote sensitive parenting among high-risk mothers. The current study used event-related potential (ERP) methodology to examine associations…

The studies reported here aimed to test the proposal that mind-mindedness is a quality of personal relationships by assessing mind-mindedness in caregiver-child dyads in which the relationship has not spanned the child's life or in which the relationship has been judged dysfunctional. Studies 1 and 2 investigated differences in mind-mindedness…

Children practice their spatial skills when playing with spatial toys, such as construction materials, board games, and puzzles. Sex and SES differences are observed in the engagement in such spatial play activities at home, which relate to individual differences in spatial performance. The current study investigated the effects of explicitly…

This study examined associations between perceived degree and style of parental prohibition and adolescents' internalization of and oppositional defiance against parental rules in the friendship and moral domain. Relations were investigated in 2 longitudinal adolescent samples (total N = 532). Results indicated that perceived style but not…

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…

Youth who experience adverse environments in early life initiate sexual activity at a younger age, on average, than those from more advantaged circumstances. Evolutionary theorists have posited that ecological stress precipitates earlier reproductive and sexual onset, but it is unclear how stressful environments interact with genetic influences on…

The recent development in the measurements of spontaneous mental state understanding, employing eye-movements instead of verbal responses, has opened new opportunities for understanding the developmental origin of "mind-reading" impairments frequently described in autism spectrum disorders (ASDs). Our main aim was to characterize the…