To illuminate individual differences in the development of attention-deficit hyperactivity disorder (ADHD) symptoms in the general population, psychometric measures are needed that can capture general population-level symptom variation reliably, validly, and comparably from childhood through to the transition to adulthood. The ADHD subscale of the…

One long-standing theoretical model of shyness proposes that the origins and maintenance of shyness are associated with an approach-avoidance motivational conflict (Asendorpf, 1990), such that shy individuals are motivated to socially engage (high approach motivation) but are too anxious to do so (high avoidance motivation). However, this model…

Longitudinal measurement enables the examination of behavioral or psychological change. One approach to examining longitudinal measurements is the use of latent growth curve modeling (LGCM). This approach affords the assessment of inter- and intraindividual change. Yet, this approach likely is underused in exercise science. The purpose of the…

Lifespan research has long been interested in how contexts shape individual development. Using the separation and later reunification of Germany as a kind of natural experiment we examine whether and how living and dying in the former East or West German context has differentially shaped late-life development of well-being. We apply multi-level…

Growth mixture modeling (GMM) is a method for identifying multiple unobserved sub-populations, describing longitudinal change within each unobserved sub-population, and examining differences in change among unobserved sub-populations. We provide a practical primer that may be useful for researchers beginning to incorporate GMM analysis into their…

Inherent limitations on the feasibility of experimentation have made it difficult for investigators to formulate an adequate understanding of individuality as a psychological phenomenon. Recently, Fiske (1979) and Sontag (1971) have suggested that application of a longitudinal or developmental strategy might be of some use in remedying this…

A 13-month study of preschoolers' conversations with friends examined development of understanding of mind and emotion and mental-state talk. Findings indicated significant and related improvements in theory-of-mind task performance and affective perspective-taking. There were qualitative and quantitative changes in mental-state references in…

Longitudinal analyses were performed on changes in life satisfaction among a sample of 378 community residents, aged 46-70. There were no significant changes in the mean life satisfaction scores for any age-sex cohort and no significant differences between the sexes, although there were some individual changes. (Author)

Examined early development of guilt in 106 children observed in laboratory paradigms in which they were led to believe they had damaged valuable objects during 2 sessions at 22, 33, and 45 months. Found support for a mediational model in which fearful temperament contributed to guilt proneness, which served to inhibit children's tendency to…

A six-year study investigated relationships between individual development and: (1) changes in aggressive expression; (2) continuities of aggressive behavior in girls and boys; and (3) convergence between self-concepts and social attributions of others in ontogeny. Participants were 220 fourth grade students who were followed from childhood…

A longitudinal study examined memory span at 5, 7, and 12 months in full-term and low-birth-weight preterm infants. Findings were similar for both groups: longer spans were more difficult, especially at younger ages, memory capacity increased over first year of life, there was marked recency effect for spans of 3 and 4 at all ages, and modest…

Examined development of child and adolescent self-concept in two overlapping age cohorts as a function of the self-concept domain, social/developmental/educational transitions, and gender. Structural equation modeling addressed questions about stability of individual differences over time. Multilevel modeling addressed questions about mean-level…

Reviews development of rehearsal and organizational strategies based on cross-sectional and longitudinal research, focusing on the Munich Longitudinal Study. Found that longitudinal data reveal greater individual variability in strategy acquisition, suggesting that canonical development patterns inferred from cross-sectional studies obfuscate…

Used Visual Expectation Paradigm to describe information processing changes and individual differences during first year of life. Found regular age changes in mean reaction time and variability but not in minimum reaction time, suggesting that growth rate of sensory-detection information is constant during first year but age changes occur in level…

Speculates on underlying processes for the reaction time variance and age differences in anticipation latency using the Visual Expectation Paradigm. Discusses the dichotomization of reactive and anticipatory behavior, limitations of longitudinal designs, drawbacks in using standard procedures and materials, and inferences that can be made…