Friendships are important sources of support during adolescence. However, a growing literature indicates some adolescents co-ruminate, or talk with friends about problems in a way that is excessive, speculative, and negatively focused, which confers risk for internalizing problems. Still, previous research had not examined the types of problems…

This preregistered, longitudinal study examined how much adolescents value and integrate their parents' and peers' attitudes into their own attitudes from early to middle adolescence. Across three waves, participants (N = 172, 91 female, 11-16 years across three waves; 439 data points) decided whether to pay money to learn their parents' or peers'…

Previous research shows that children evaluate the competence of others based on how effectively someone accomplished a goal, that is, based on the observed outcome of an action (e.g., number of attempts needed). Here, we investigate whether 5- to 10-year-old children and adults infer competence from how efficiently someone solves a task by…

In the present research, we provide empirical evidence for the process of symbolic integration of number associations, focusing on the development of simple addition (e.g., 5 + 3 = 8), subtraction (e.g., 5 - 3 = 2), and multiplication (e.g., 5 × 3 = 15). Canadian children were assessed twice, in Grade 2 and Grade 3 (N = 244; 55% girls). All…

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…

The interrelationships between math and behavioral skill development prior to school entry are not well understood, yet have important implications for understanding how to best prepare young children for kindergarten. This study addresses this gap by utilizing a sample of 1,750 children (53% male; 47% White, 16% Black, 16% Hispanic, 8% Asian, and…

Parasympathetic nervous system functioning as indexed by respiratory sinus arrhythmia (RSA) is widely used as a measure of physiological regulation. We examined developmental patterns of children's resting RSA and RSA reactivity from 2 to 15 years of age, a period of time that is marked by considerable advances in children's regulatory abilities.…

Complexity is one of the major demands of adolescents' future life as adults. To investigate adolescents' competence development in applying problem-solving strategies in complex environments, we conducted a 2-wave longitudinal study in a sample of Finnish adolescents (11-17 years old; N = 1,959 at Time 1 and N = 1,690 at Time 2, 3 years later).…

Anger is a central characteristic of negative affect and is relatively stable from infancy onward. Absolute levels of anger typically peak in early childhood and diminish as children become socialized and better able to regulate emotions. From infancy to school age, however, there are also individual differences in rank-order levels of anger. For…

Evidence from physiological studies has been integral in many causal theories of behavioral and emotional problems. However, this evidence is hampered by the heterogeneity characterizing these problems. The current study adds to prior work by identifying neuro-physiological markers associated with heterogeneity in conduct problems (CP),…

This longitudinal study examined coparenting and child adjustment during early and middle childhood (Ms = 3 and 8 years, respectively) among 106 lesbian, gay, and heterosexual parent adoptive families. When children were in middle childhood, no differences emerged as a function of parental sexual orientation in observations or self-reports of…

Basic perspective taking and mentalizing abilities develop in childhood, but recent studies indicate that the use of social perspective taking to guide decisions and actions has a prolonged development that continues throughout adolescence. Here, we aimed to replicate this research and investigate the hypotheses that individual differences in…

This article used a sample of 2 adolescents per family to (a) examine the extent to which parental monitoring and adolescent information management are characteristics of families or of dyads and (b) replicate past research on parental monitoring and adolescent information management using models that distinguish differences between families from…

The current 3-generation (N = 204 families), 3-year longitudinal study examined the intergenerational transmission of cultural socialization among Mexican-origin young mothers and their own mothers (i.e., children's grandmothers) and, in turn, whether young mothers' cultural socialization informed their children's developmental competencies (i.e.,…

This research examined whether following social and physical aggression trajectories across Grades 3-12 predicted psychological maladjustment. Teachers rated participants' (n = 287, 138 boys) aggressive behavior at the end of each school year. Following the 12th grade, psychosocial outcomes were measured: rule-breaking behaviors, internalizing…