It has been argued that facets do not represent the bottom of the personality hierarchy-even more specific personality characteristics, nuances, could be useful for describing and understanding individuals and their differences. Combining 2 samples of German twins, we assessed the consensual validity (correlations across different observers), rank-order stability, and heritability of nuances. Personality nuances were operationalized as the 240 items of the Revised NEO Personality Inventory (NEO-PI-R). Their attributes were examined by analyzing item residuals, controlling for the variance of the facet the item had been assigned to and all other facets. Most nuances demonstrated significant (p < .0002) cross-method agreement and rank-order stability. A substantial proportion of them (48% in self-reports, 20% in informant ratings, and 50% in combined ratings) demonstrated a significant (p < .0002) component of additive genetic variance, whereas evidence for environmental influences shared by twins was modest. Applying a procedure to estimate stability and heritability of true scores of item residuals yielded estimates comparable with those of higher-order personality traits, with median estimates of rank-order stability and heritability being .77 and .52, respectively. Few nuances demonstrated robust associations with age and gender, but many showed incremental, conceptually meaningful, and replicable (across methods and/or samples) predictive validity for a range of interest domains and body mass index. We argue that these narrow personality characteristics constitute a valid level of the personality hierarchy. They may be especially useful for providing a deep and contextualized description of the individual, but also for the prediction of specific outcomes. (PsycINFO Database Record

Most theories of personality development posit that changes in life circumstances (e.g. due to major life events) can lead to changes in personality, but few studies have examined the exact time course of these changes. In this article, we argue that time needs to be considered explicitly in theories and empirical studies on personality development. We discuss six notions on the role of time in personality development. First, people can differ before the event. Second, change can be non‐linear and discontinuous. Third, change can be reversible. Fourth, change can occur before the event. Fifth, control groups are needed to disentangle age‐related and event‐related changes. Sixth, we need to move beyond examining single major life events and study the effects of non‐normative events, non‐events, multiple events, and minor events on personality. We conclude by summarizing the methodological and theoretical implications of these notions. Copyright © 2014 European Association of Personality Psychology

The present study examined the patterns and sources of 10-year stability and change of adult personality assessed by the 5 domains and 30 facets of the Revised NEO Personality Inventory. Phenotypic and biometric analyses were performed on data from 126 identical and 61 fraternal twins from the Bielefeld Longitudinal Study of Adult Twins (BiLSAT). Consistent with previous research, LGM analyses revealed significant mean-level changes in domains and facets suggesting maturation of personality. There were also substantial individual differences in the change trajectories of both domain and facet scales. Correlations between age and trait changes were modest and there were no significant associations between change and gender. Biometric extensions of growth curve models showed that 10-year stability and change of personality were influenced by both genetic as well as environmental factors. Regarding the etiology of change, the analyses uncovered a more complex picture than originally stated, as findings suggest noticeable differences between traits with respect to the magnitude of genetic and environmental effects.

Increasing numbers of empirical studies provide compelling evidence that personality traits change across the entire lifespan. What initiates this continuing personality development and how does this development proceed? In this paper, we compare six theoretical perspectives that offer testable predictions about why personality develops the way it does and identify limitations and potentials of these perspectives by reviewing how they hold up against the empirical evidence. While all of these perspectives have received some empirical support, there is only little direct evidence for propositions put forward by the five‐factor theory of personality and the theory of genotype → environment effects. In contrast, the neo‐socioanalytic theory appears to offer a comprehensive framework that fits the empirical findings and allows the integration of other, more specialized, perspectives that focus on specific aspects of personality development like the role of time, systematic differences between categories of social roles or the active partake of the person himself or herself. We draw conclusions on the likely driving factors for adult personality development and identify avenues for future research. Copyright © 2014 European Association of Personality Psychology

The importance of personality for predicting life outcomes in the domains of love, work, and health is well established, as is evidence that personality traits, while relatively stable, can change. However, little is known about the sources and processes that drive changes in personality traits and how such changes might impact important life outcomes. In this paper, we make the case that the research paradigms and methodological approaches commonly used in personality psychology need to be revised to advance our understanding of the sources and processes of personality change. We propose Longitudinal Experience‐Wide Association Studies as a framework for studying personality change that can address the limitations of current methods, and we discuss strategies for overcoming some of the challenges associated with Longitudinal Experience‐Wide Association Studies. © 2020 European Association of Personality Psychology

Environmental factors shared by co-twins affect BMI in childhood, but little evidence for their contribution was found in late adolescence. Our results suggest that genetic factors play a major role in the variation of BMI in adolescence among populations of different ethnicities exposed to different environmental factors related to obesity.

Individual differences in personality are often described on the basis of a small set of dimensional core characteristics that are commonly defined as largely consistent patterns of thoughts, feelings and actions across time and situations. Some theoretical approaches even consider them to provide the biologically founded basis for individual differences in so‐called surface characteristics such as self‐related evaluations, social attitudes, values, goals or interests, which are commonly hypothesized to be less stable or more environmentally malleable than core characteristics. We examine these hypotheses by reviewing findings about potential core and surface characteristics on the basis of four criteria: (i) level of stability in individual differences; (ii) level of heritability; (iii) direction of causation; and (iv) shared genetic variance. The results from our review call into serious question the labelling of some sets of constructs as either core or surface characteristics of personality. Although certain dimensions—often labelled as basic traits (e.g. extraversion)—are systematically linked to more specific characteristics (e.g. social attitudes and interests), the so‐called basic traits do not appear to provide an essential basis (i.e. the more stable and genetically anchored source) for these characteristics. We argue for more integrative models of personality in adulthood. Copyright © 2014 European Association of Personality Psychology

The occurrence of many life events is not entirely random but genetically influenced. The current study examined the sources underlying the stability or recurrence of life events and the developmental interplay between personality traits and life events. In a longitudinal study of 338 adult twin pairs we estimated (1) the genetic and environmental sources of continuity in aggregates of life events, (2) the sources through which personality influences the experience of life events, and (3) the sources through which life events influence personality. Unlike personality which showed both genetic and environmental influences on substantial continuity over time, stability of life events was moderate and mainly influenced by genetic factors. Significant associations between personality and life events were specific to certain personality traits and qualitative aspects of life events (controllable positive, controllable negative, and less controllable negative), primarily directional from personality to life events, and basically genetically mediated. Controlled for these genetic associations, we also found some small and basically environmentally mediated effects of life events on personality traits. The results support the concept of genotype-environment correlation as a propulsive mechanism of development.