Personality development between nature and nurture

and increasing generalizability. Domain sampling models of reliabil- ity are based upon the random choice of items and now subjects can be randomly assigned to presentation conditions. The study of individual differences has gone far beyond simple correlation and simple randomization of conditions. Correlational designs are sometimes hard to distinguish from true experiments, as we analyze data at multiple levels of analysis, over multiple time points, with multiple classes of measures. We can conduct experi- ments, or in the case of behavior genetics, allow nature to conduct the experiment. By integrating correlational and experimental techniques, and by taking advantage of the new tools available to us, we can all further the unification of our field and go beyond Eysenck’s challenge to develop a science of personality and individual differences. Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.paid.2013.12.007. http://dx.doi.org/10.1016/j.paid.2013.12.007 Robert Krueger Keynote Personality, psychopathology, individual differences, and DSM-5 Robert F. Krueger The American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (5th Edition; DSM-5) was published in May 2013. This talk will focus on how DSM-5 is (and is not) con- nected with research in personality and individual differences. For example, relative to DSM-IV, DSM-5 is better connected with per- sonality and individual differences because it encompasses an empirically-based model of maladaptive personality traits, and an associated assessment instrument, the Personality Inventory for DSM-5 (PID-5). Nevertheless, much of DSM-5 remains constrained by the psychiatric proclivity to conceptualize psychopathology in terms of numerous putatively discrete categories, despite extensive evidence to the contrary of this conceptualization. Although numer- ous political and scientific challenges remain, working to enhance the connection between Psychiatry and individual differences research will ultimately enrich both areas. Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.paid.2013.12.003. http://dx.doi.org/10.1016/j.paid.2013.12.003 Roberto Colom Keynote From the Earth to the brain Roberto Colom Intelligence is a trait of paramount relevance for understanding human behavior, mainly because of its integrative nature. Intelli- gence is like the sun and the remaining psychological traits describe orbits around. Some are closer than others. Many are far away. I will underscore the view that scientists are urged to adopt simplified frameworks. Brave simple-minded hypotheses are wanted. Let’s focus on the brain and how everything out there is organized indoors to produce intelligent behavior. We must understand how different brains actually work. European and North-American researchers are currently integrating efforts to this end. Psychologists must join them and stop saying that there are many interesting things under the stars deserving a close scrutiny. This is true, but not really useful. All we need is a deep understanding of how different brains work. Novel descriptions of what happens in the brain when facing situa- tions requiring intelligence will be derived from the use of technol- ogy developments. The (American) Brain Activity Map Project (BAM) and the (European) Human Brain Project (HBP) will help intelligence researchers to test new ideas and approaches. The novel descriptions will tell that not all brains work the same way for achieving comparable goals. The brain is a general-purpose device and it is also highly dynamic. Scientists will describe and characterize ‘personalized brains’ (individual connectomes equiva- lent to individual genomes). At the end of the day, science will find methods for improving our brains by pharmacological/neurological (smart pills/transcranial magnetic stimulation, TMS) and behavioral treatments based on adaptive cognitive challenges that cannot be automated. Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.paid.2013.12.008. http://dx.doi.org/10.1016/j.paid.2013.12.008 Early Career Award Award keynote Sophie von Stumm This talk discusses the far-reaching consequences of individual differences in intelligence for people’s lifespan development on the one hand, and on the other, if, to what extent, and why individual differences in intelligence may change over time. To this end, the relationship between childhood intelligence and later life outcomes, such as social status attainment, health and marital status, is reviewed first. Next, the development of individual differences in intelligence from infancy through adolescence is outlined, as well as possible environmental and genetic causes of such differences. Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.paid.2013.12.009. http://dx.doi.org/10.1016/j.paid.2013.12.009 Early Career Award Personality development between nature and nurture Christian Kandler Different types of continuity and change have revealed interest- ing developmental patterns of personality traits across the life span. The stability (i.e., rank-order, individual, and profile continuity) of Keynotes / Personality and Individual Differences 60 (2014) S79–S82 S81 personality traits tends to increase from .30 in childhood until it plateaus between .70 and .80 in middle adulthood (Roberts & DelVecchio, 2000; Terracciano, McCrae, & Costa, 2010). The continu- ity finally appears to decrease in old age (Lucas & Donnellan, 2011). Mean-level and individual-level change occur across the entire life span and stability tends to decrease as the time intervals between occasions of personality assessment increase (Fraley & Roberts, 2005; Soto, John, Gosling, & Potter, 2011). These patterns show that personality development is a lifelong process. Though personality is relatively stable in middle adulthood, personality change is possible in every age, in particular in young and old ages, and the more time goes by, the more change is likely. Yet the sources of these patterns are unknown. Some theories suggest that the patterns of personality continuity and change may result from age-graded social roles, individual life experiences and major life transitions reflecting an environmental maturation to a socially and culturally functional identity (Roberts & Jackson, 2008; Roberts, Wood, & Caspi, 2008). Other theories, however, explain con- tinuity by genetic set-points and change by biological maturation and short-term but reversible environmental changes (Carey, 2002; McCrae & Costa, 2008). Whereas phenotypic findings provide partial support for both perspectives on personality development, genetically informative and environmentally sensitive longitudinal studies across different age cohorts allow a differentiated picture of genetic and environmental sources of personality development. I will give a short overview of the genetic and environmental contributions to the rank-order stability and change of Neuroticism and Extraversion (Kandler, 2012). Both genetic and environmental factors contribute to continuity and change, but genetic factors represent the primary source of continuity and appear to affect change only in younger decades of life, whereas environmental influences appear to repre- sent a lifelong source of personality development. Heritability of Neuroticism and Extraversion progressively decreases after people enter adulthood due to an increase of environmental variance com- pared to the genetic variance. The findings indicate a model of personality development that integrates genetically driven development (e.g., niche-picking) and social maturation (e.g., changes in social roles and social identity for- mation). Personality development is a complex affair. We can only understand the complete picture, if we focus on both genetic and environmental processes as well as the complex interplay between nature and nurture (e.g., processes of individual adaptation to main- tain the created niches and the functionality of identity). Appendix A. Supplementary data Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.paid.2013.12.002. http://dx.doi.org/10.1016/j.paid.2013.12.002 S82 Keynotes / Personality and Individual Differences 60 (2014) S79–S82 p0035 p0015 p0040 p0040 Appendix A Supplementary data Appendix A Supplementary data Appendix A Supplementary data Appendix A Supplementary data Appendix A Supplementary data