Behavioral inhibition (BI) is an early-appearing temperamental trait characterized by intense negative affect and withdrawal behaviors to novel and challenging situations. Inhibited children are more likely to display social withdrawal and experience an increased risk for internalizing problems. Trait inference, the way children interpret…

There is considerable variability in the extent to which young people with developmental language disorder (DLD) experience mental health difficulties. What drives these individual differences remains unclear. In the current article, data from the Twin Early Development Study were used to investigate the genetic and environmental influences on…

Research shows greater mindfulness is associated with less negative affect and more positive affect. Fewer studies have examined the mediating psychological processes linking mindfulness to these outcomes in adolescents. This three-wave, prospective longitudinal study examines rumination--the tendency to engage in repetitive and negative…

Exposure to deviant friends has been found to be a powerful source of influence on children's and adolescents' aggressive behavior. However, the contribution of deviant friends may have been overestimated because of a possible non-accounted gene-environment correlation (rGE). In this study, we used a cross-lagged design to test whether friends'…

Adolescent stress-related growth refers to enhancement in an adolescent's cognitive-affective or social resources as a result of experiencing stressors. We tested whether adolescents reporting high levels of stress-related growth showed superior adaptation outcomes on a day-to-day basis. Participants (n = 91; females = 46, age = 14) completed a…

For many African Americans, racial identity is an important aspect of their individual identity. We explored developmental change and stability of individual differences in the racial centrality of African American youths and their mothers as well as the relation between maternal and child racial centrality across time. African American youths (N…

Although spending time in criminogenic settings is increasingly recognized as an explanation for adolescent delinquency, little is known about its determinants. The current study aims to examine the extent to which (change in) self-control and (change in) delinquent attitudes relate to (change in) time spent in criminogenic settings, and the…

This longitudinal study aimed to differentiate between acculturative and developmental processes by (a) comparing levels and change rates in victimization among ethnic German immigrants and native German adolescents in Germany and Russian Jewish immigrants in Israel, and (b) testing whether interindividual differences in victimization among…

Given the sharp increase in rates of depression during adolescence, especially in girls, it is important to identify which youth are at greatest risk across this critical developmental transition. During the present research, we examined whether (a) individual differences in cognition-emotion interaction, as reflected in cognitive control (CC)…

The current study investigated the development of global and domain (academic, physical, same-sex peer relationship, opposite-sex peer relationship) self-esteem from age 10 to 16 in a sample of Mexican-origin adolescents. Participants' (N = 674) responses on the Self-Description Questionnaire (SDQ; Marsh, 2005) II-S showed moderate rank-order…

In order to advance our understanding of educational processes, we present a tutorial of intraindividual variability. An adaptive educational process is characterised by stable (less variability), and a maladaptive process is characterised by instable (more variability) learning experiences from one learning situation to the next. We outline step…

Late-life well-being often shows steep deteriorations, but the contributing factors are not well understood, in part because data about people's final year of life are scarce. Here, we draw from and test theoretical perspectives that health-related vulnerabilities undermine the experience and skills older adults typically use to maintain…

Most of the individual difference variance in the population is found "within" families, yet studying the processes causing this variation is difficult due to confounds between genetic and nongenetic influences. Quasi-experiments can be used to test hypotheses regarding environment exposure (e.g., timing, duration) while controlling for…

Adults demonstrate difficulty and pronounced variability when developing second language (L2) grammatical knowledge and reading skills. We examine explanations in terms of individual differences in working memory (WM). Despite numerous studies, the association between WM and adult second language (L2) acquisition remains unclear, and longitudinal…

The present longitudinal study examines the interaction of learner variables (gender, motivation, self-efficacy, and first language literacy) and their influence on second language learning outcomes. The study follows English learners of French from Year 5 in primary school (aged 9-10) to the first year in secondary school (Year 7; aged 11-12).…