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Personality Development
Personality Development M B Donnellan, Michigan State University, East Lansing, MI, USA R W Robins, University of California, Davis, CA, USA ã 2012 Elsevier Inc. All rights reserved.
Glossary Cumulative continuity prinicple The observation that individual differences become more stable (or less malleable) with age. Dispositions Stable tendencies to think, feel, and behave in certain ways. Heterotypic stability Consistency in the same underlying personality disposition across development that may nonetheless demonstrate different behavioral manifestations at different ages. Homotypic stability Consistency in the same manifestations of personality across development. Intrinsic maturation hypothesis The perspective that changes in levels of personality traits in adulthood are generated by biological processes residing within the individual.
Personality refers to an individual’s stable tendencies to think, feel, and act in particular ways. The field of personality psychology focuses on understanding and assessing these individual differences in thoughts, feelings, and behavior. Accordingly, the subfield of personality development generally seeks to (1) describe patterns of stability and change in personality dispositions across the life span, (2) evaluate the influence of genetic and environmental factors on personality development, and (3) identify the processes that generate both consistency and change in personality dispositions from infancy to old age. Researchers typically address these types of questions using longitudinal designs in which the personality attributes of the same group of participants are assessed repeatedly across an appreciable span of development. Personality is most frequently assessed via self-reports and ratings of the participant by knowledgeable others (peers, parents, teachers); other commonly used assessment methods include observations of behavior in standardized situations; reaction times and other measures of cognitive processing; experience sampling; and a wide range of physiological measures. In this article, we outline three general levels at which personality can be conceptualized, discuss several types of personality stability and change, and then summarize the most recent findings and conclusions emerging from this exciting and interdisciplinary branch of psychology.
Considering Personality at Multiple Levels What are the building blocks of personality; that is, what are the fundamental ways in which individuals differ from each other? McAdams and Pals have proposed an integrative approach that conceptualizes personality at three levels of
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Life course hypothesis The perspective that adult personality changes result, in part, because of investment in adult social roles. Maturity principle The observation that personality trait changes in adulthood facilitate the fulfillment of adult roles (e.g., increases in agreeableness and conscientiousness). Mean-level stability Consistency in average levels for a given trait across developmental periods. Rank-order stability Consistency in the relative ordering of individuals for a given trait across developmental periods. Temperament The term usually refers to the dispositional attributes of young children. However, temperament can also generally refer to biologically based individual differences regardless of developmental period.
individual variability. The first level reflects those dispositional traits that reflect an individual’s general style of adjustment and approach to the social world. Although there are thousands of dispositional traits, personality psychologists generally agree that these traits can be usefully organized into five broad domains: extraversion (talkative, enthusiastic vs. quiet, reserved), agreeableness (kind, sympathetic vs. critical, quarrelsome), conscientiousness (reliable, self-disciplined vs. disorganized, careless), neuroticism (anxious, easily upset vs. calm, emotionally stable), and openness to experience or simply openness (imaginative, novelty seeking vs. uncreative, conventional). These trait domains (commonly referred to as the ‘Big Five’) are relatively consistent over the life course, generalize across cultures, and emerge in childhood. The Big Five have been linked to a variety of genes, neurotransmitters, brain structures, and neural activation patterns. These domains also predict a wide range of important life outcomes, including academic achievement, crime and delinquency, health and longevity, job performance, personality disorders, and relationship satisfaction. The other two levels in the framework of McAdams and Pals are characteristic adaptations and life narratives. Characteristic adaptations capture differences in motives and social cognitive processes such as the internal representations of key relationship partners (e.g., parents, romantic partners). These elements of personality are more contextualized than dispositional traits, and thought to be more responsive to situational forces. The third level captures those ongoing personal stories or narratives that individuals use to construct meaning from their lives. This level of individuality captures an individual’s ‘life story’ and is the bedrock of identity. Most research on personality development has focused on the level of core dispositions. In other words, more is known about the development of the Big Five domains than
Personality Development
characteristic adaptations and life stories. This will probably change in the future as researchers use large-scale longitudinal designs to study constructs at the other two levels of individuality. Nonetheless, this article focuses on dispositional traits because of the dearth of developmental research on the other two levels. However, it is important to keep in mind that there are other ways of characterizing individuals and these other levels of personality also have a developmental dimension.
Defining Different Types of Stability and Change Just how stable are personality dispositions across the life span? There are no easy ways to answer this question because there are different ways of conceptualizing and measuring stability and change in personality. A broad distinction is often made between homotypic and heterotypic stability (or continuity). Homotypic stability concerns the degree to which people express the same thoughts, feelings, and behaviors across time. This kind of stability focuses on the same manifestations of personality across time. In contrast, heterotypic stability refers to the consistency of the underlying personality traits that are theorized to have different observable manifestations at different ages. The investigation of heterotypic stability requires a conceptual understanding of the underlying personality disposition. That is, researchers must draw on a theory to specify how the same underlying personality disposition will appear to outside observers at different ages. The central issue is that many of the more salient behaviors associated with particular personality traits seem to change with development. A shy child might cling to his or her parent in the middle of a crowded room, whereas a shy adult might simply avoid large social gatherings altogether. Likewise, an aggressive toddler might bite classmates and throw temper tantrums, whereas an aggressive teen might use hostile words to insult classmates or use weapons to assault strangers. A theory about the nature of the underlying personality traits (shyness and aggressiveness, respectively) should be able to explain how these different surface manifestations reflect the same underlying personality dispositions. In contrast to heterotypic stability, the assessment of homotypic stability is less conceptual and more statistical. Homotypic stability concerns the evaluation of different kinds of change using the same measure of personality across time or across age groups. This broad category includes several specific types of stability and change. One type concerns the psychometric properties of the measurement instrument and is investigated under the term measurement stability. Two other types of stability and change are typically examined at the level of the sample and refer to particular personality attributes: mean-level stability and rank-order stability (also referred to as differential stability). Researchers can also investigate stability at the individual level by determining whether a particular individual increased or decreased in his or her absolute or relative trait standing over time. Investigations of measurement stability evaluate developmental changes in the measures used to assess personality attributes. This kind of stability is important because it helps researchers confirm that they are assessing the same psychological construct at different points in time (e.g., in childhood
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and adolescence). If measurement stability is not found, then researchers may wrongly infer that personality change has occurred when all that has happened is that the measure is tapping into a different construct across assessment occasions. Measurement properties can change even if the same items and item responses are used at two separate time points. A great deal of research in personality development focuses on mean-level stability, which refers to consistency in the average or typical level of a given trait across different developmental periods. One approach is to compare average scores for a personality attribute across different age groups, such as comparing the average level of shyness in samples of children, adolescents, and young adults. Results from these kinds of cross-sectional studies suggest that middle-aged adults (e.g., adults age 40–50) are higher in conscientiousness than teenagers. One problem with this research strategy is that age differences are conflated with birth cohort differences. Although middle-aged adults may actually be more conscientious than teenagers, it is also possible that individuals born in the 1950s are higher in conscientiousness than individuals born in the 1970s due to changes in cultural norms and expectations. The effects of age and birth cohort are inseparably confounded in a cross-sectional study. A better approach is to examine personality changes by following the same individuals over time using a longitudinal design. This method allows researchers to test whether average levels of conscientiousness increase for the same group of individuals as they mature from adolescence to adulthood. Investigations focused on average levels of personality attributes at different ages are sometimes called investigations of ‘normative’ personality differences because they provide information about the personality characteristics of the so-called ‘typical’ person at different stages of life. A concern is that average trends may obscure a great deal of individual variability in the way people change. Although conscientiousness may increase on average from adolescence to middle age, it is possible that it increases substantially in some individuals, in some only slightly, and in some it actually decreases. Given this possibility, some researchers prefer to focus on individual trajectories of personality development to determine how well each person in a sample follows the overall mean-level trends for the sample. Techniques for these analyses range from sophisticated growth curve models applied to multiwave data to fairly simple indices of real change, based on difference scores computed across two measurement occasions. Another popular area of research in personality development concerns the study of rank-order stability. A longitudinal design is required to investigate rank-order stability as it is typically measured using the correlation between the same personality measures administered at two time points but across an interval of sufficient length that will allow for the possibility of real personality change (e.g., more than a few months). These correlations are often called stability coefficients and they reflect the degree to which the relative ordering of individuals on a given trait is consistent over time. If researchers observe a high degree of rank-order stability for aggressiveness, it would mean that relatively aggressive adolescents tend to grow into relatively aggressive adults, regardless of any normative increases or decreases in aggressiveness that may co-occur with age. Rank-order stability is distinct from absolute stability
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because individuals may experience an overall decline or increase in absolute levels with age but nonetheless maintain their same position relative to others (e.g., there are large normative increases in height across development, but individuals generally maintain a similar rank ordering). A high degree of rank-order consistency is integral to the concept of a personality disposition. In summary, there are a number of conceptually and methodologically distinct ways of addressing questions about personality stability and change. This diversity requires the use of precise language to specify the exact type of consistency and change under investigation. Nonetheless, researchers strive to address all types of stability to provide a comprehensive picture of personality development. We now turn to summarizing basic findings about personality development across the life span.
Early Emerging Personality Attributes: Child Temperament Do emotionally reactive and difficult toddlers become aggressive adults? Do fearful infants become anxious adults? A key research issue in personality development concerns these questions about personality coherence or whether instantiations of individuality in young children are elaborated into adult personality traits. To be sure, individual differences are noticeable in even very young children. Some newborns are extremely fussy and difficult to soothe whereas other newborns are tranquil and easy to comfort. As newborns develop throughout infancy, they exhibit increasingly complex responses to the environment. Emotional reactions, ways of interacting with caregivers, and responses to the broader environment become more differentiated and patterned with age. At some point, these characteristics coalesce into the early emerging individual differences that are commonly referred to as attributes of childhood temperament. Mary Rothbart and John Bates provided one of the most widely used definitions of temperament: “constitutionally based individual differences in emotional, motor, and attentional reactivity and self-regulation.” An important element of this definition is the emphasis on dimensions of individuality that are thought to be rooted in biology. However, temperament researchers acknowledge that nearly all early emerging individual differences are affected by life experiences as well as by genetically influenced tendencies and other physiological factors. A second important element of this definition is an emphasis on emotional processes as many of the separate dimensions of temperament reflect individual differences in the functioning of affective systems that motivate behavior in either an approach or avoidance fashion. As with the research on the structure of adult personality traits that seeks to identify a set of basic domains that can be integrated into a hierarchical structure ranging from broader to narrower dispositions, researchers also seek to identify the basic dimensions and organizing structure of childhood temperament. One prominent model for childhood temperament identifies three broad dimensions – positive emotionality, negative emotionality, and constraint versus disinhibition. Positive emotionality captures the tendencies to approach the environment and engage in interactions with others
(i.e., extraversion). Negative emotionality captures the tendencies to become distressed, experience aversive emotions, and feel threatened (i.e., neuroticism). Constraint versus disinhibition captures the ability to exercise control over impulses and direct behavior toward achieving longer term goals (i.e., conscientiousness). A largely complementary approach classifies temperamental dimensions using childhood analogs of the Big Five dimensions of adult personality – extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience – to organize the dimensions of childhood temperament. Indeed, some researchers actually consider the Big Five to be the dimensions of temperament. These domains are evident in adolescents and even in children as young as 5 years of age. The one caveat is that openness to experience may not have a clear parallel in childhood temperament. The difficultly in linking openness to experience with childhood temperament is perhaps not surprising given that openness seems to have the least consistent link with neurological systems in the brain. As it stands, there is evidence for a connection between childhood temperament and adult personality. A complication is that longitudinal research focused on the same dispositions from childhood to adulthood is fairly rare. This should change as more and more longitudinal studies are designed to explicitly address this important question. One of the most recent and impressive examples of personality coherence comes from a study of the Hawaii Personality and Health Cohort. Investigators of this project have followed roughly 2404 individuals from the time they were elementary school children in the early 1960s to the present. A team of investigators video recorded a subset of these individuals when they were middle-aged adults. These recordings were then coded for a diverse range of personality attributes by trained coders. There was an appreciable correlation between the ratings of the individuals made by their elementary school teachers and the observer ratings of those same individuals at midlife. Individuals rated as talkative by teachers in elementary school developed into middle-aged adults who were rated as socially dominant and assertive by observes. Individuals rated as able to cope with new situations and face uncertainty were rated as cheerful and self-confident as middle-aged adults. A key message from this study is that there is a meaningful personality coherence from childhood to middle age. In a similar vein, researchers studying a cohort of individuals born in New Zealand have found meaningful associations between ratings of 3-year-old children made by clinical interviewers and adult outcomes at age 21. Children who were rated as being irritable and impulsive at age 3 were more likely to be dependent on alcohol and to have been convicted of a violent crime by age 21. The fact that there is a connection between preschool attributes and problems with alcohol and violence during early adulthood is impressive evidence for the coherence of traits related to difficulties with impulse control. This work also points to personality coherence across development even when considering the personality attributes of very young children. All in all, efforts to integrate childhood temperament with adult personality are progressing as researchers converge on a set of basic dimensions that are relevant for adaptation across the life span. This effort at integration will take some time,
Personality Development
however, because it will be years and even decades before participants in newly initiated studies mature from children into adults. Nonetheless, efforts to unify research on childhood temperament and adult personality represent an exciting area of synergy between developmental psychology and personality psychology that may help to curb the ‘jangle fallacy’ that permeates psychological science (i.e., if two constructs have different names then they must be different).
Mean-Level and Rank-Order Stability of the Big Five Across the Life Span What are the patterns of normative personality development? What is the pattern of rank-order stability across the life span? Summarizing research on these topics has been greatly facilitated by a number of meta-analyses that were conducted in the last decade. A meta-analysis is a statistical approach for summarizing research literatures and essentially involves averaging the results from all available studies. This method permits researchers to quantify findings across the entire research literature and is perhaps optimal to narrative reviews, which simply provide qualitative impressions of previous work. A meta-analysis by Roberts, Walton, and Viechtbauer provided a summary of average levels of the Big Five traits using data from 113 longitudinal samples involving 50 120 participants ranging in age from adolescence through old age. These researchers divided the extraversion domain into two facets: social dominance (traits related to independence and dominance) and social vitality (traits related to positive affect, activity level, and sociability). Average levels of social vitality tended to be fairly flat across the life span, although there was a slight spike upward from adolescence to young adulthood followed by a plateau until the mid-50s when there was a slight decline. Social dominance, on the other hand, showed a more pronounced trend such that there was a consistent absolute increase from adolescence to the early 30s where mean levels remained consistent until the mid-50s, after which the lack of studies precluded further analyses. Agreeableness and conscientiousness showed gradual increases in absolute scores across the life span whereas neuroticism showed gradual decreases. Finally, openness showed a mean-level increase from adolescence to young adulthood and then mean levels remained constant until the mid-50s when it started to show a slight decline in average levels. One of the more interesting results that emerged from this meta-analysis concerned the adolescent period. Contrary to the popular belief that adolescence involves tumultuous changes in personality, the Roberts et al. meta-analysis demonstrated that the largest mean-level changes in personality occur during the young adult years (i.e., the 20s). This is the phase in the life span when individuals assume the roles of worker, committed romantic partner, and in many cases, parent and caregiver. Furthermore, it is easy to see how increasing levels of agreeableness and conscientiousness and decreasing levels of neuroticism facilitate the successful enactment of the roles of worker, parent, and committed romantic partner. Thus, average levels of traits change in ways that coincide with the time in the life span during which individuals assume mature social roles, a pattern referred to as the maturity principle of adult personality development.
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In summary, the available data indicate that average levels of agreeableness and conscientiousness increase with age whereas average levels of extraversion (in the aggregate), neuroticism, and openness decline with age. There are two dominant explanations for these mean-level differences in the Big Five domains across the life span. The intrinsic maturational position holds that normative age-related changes in personality are driven by unfolding biological processes related to aging whereas the life course position posits that changes stem from investment in particular social roles and the life experiences that accompany these roles. Researchers are currently debating which perspective has the most empirical support. One of the complicating factors is that critical tests of these two explanations are nearly impossible because experimental manipulations of either biological factors or important social roles are neither ethical nor feasible. At least two different meta-analyses have investigated rankorder stability across the life span. Roberts and DelVecchio examined test–retest correlations from 152 longitudinal studies and found that the rank-order stability of personality increases across the life span, ranging from a low around 0.30 in childhood to a high of 0.70 in late adulthood. This pattern generally held for men and women and for all five of the Big Five traits. A more recent meta-analysis by Ferguson reached similar conclusions, although in his analysis rank-order stability reached a plateau earlier in development than in the Roberts and DelVecchio analysis (perhaps because he corrected the rank-order stability estimates for measurement error). The finding that the rank-order stability of personality increases from childhood to adulthood is known as the cumulative continuity principle of personality development – that is, personality becomes increasingly stable with age (when viewed through the lens of rank-order stability). This naturally raises questions as to why rank-order stability increases with age. Lower stability is expected when individuals respond to experiences differently or experience personality-altering environments at different times. The transition from childhood to adolescence involves rapid maturational changes, shifting societal demands, exploration of new identities and roles, and initiation of new peer and romantic relationships. These changes may impact individuals in relatively unique ways, thus shifting their relative ordering on a trait and thereby reducing stability coefficients. In contrast, the transition to adulthood is accompanied by fewer maturational changes and social transitions that begin to stabilize. Likewise, a hallmark of adulthood is the increased ability to select environments consistent with individual dispositions. These broad developmental considerations may explain the cumulative continuity principle. Indeed, researchers are now moving beyond simply documenting patterns of mean-level and rank-order stability to testing hypotheses about the underlying mechanisms that produce personality consistency and change.
What Mechanisms Account for Personality Stability and Change? What specific mechanisms account for the stability of personality over time and, conversely, what account for change? Contemporary research suggests that personality stability and change result from complicated transactions between
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persons and situations. Three processes in particular might promote stability in personality by producing a correspondence between personality traits and characteristics of the social environment. First, personality traits ‘draw out’ or otherwise evoke corresponding responses from the social environment. This matching between the underlying dimension and the environmental response or reaction may reinforce both the disposition and the individual’s social ecology. This process would tend to promote personality continuity. For example, individuals who are aggressive may evoke more hostile responses from classmates and coworkers. These hostile responses may then accentuate the initial tendency toward aggressiveness. In short, it seems as if many individual dispositions generate responses in social environments which end up reinforcing those very dispositions. Second, personality traits shape how people interpret social situations that can have real consequences for behavior and its effects. The same objective environment, such as a cocktail party, may prove stimulating and exciting to an extraverted individual but terrifying to an introverted person. These different construals of the same objective environment might facilitate self-fulfilling prophecies. The scared introvert might act awkward and stand-offish to fellow party guests, thereby generating unpleasant and strained interpersonal encounters. The upshot is that this process would also tend to reinforce initial personality dispositions. Third, personality traits can influence the settings that individuals select and create for themselves. One of the consequences of human agency and autonomy is that individuals have the freedom to seek out, modify, and even create environments that are consistent with their individual characteristics. The characteristics of individuals and the characteristics of their social situations are therefore correlated. For example, what people do for a living and how they structure their environments may reflect their personalities. These social contexts may then help to maintain the personality characteristics that were initially responsible for the selection processes in the first place. Individuals who are outgoing and sociable may choose careers that fit well with these tendencies and shun solitary occupations with limited potential for social interaction. Such a career may enhance and sustain these extraverted tendencies. The upshot of these three mechanisms is that many life experiences serve to deepen and intensify the personality characteristics that were partially responsible for the environmental or social experiences in the first place. This is known as the corresponsive principle of personality development. The principle would naturally promote personality consistency across developmental periods. A different set of mechanisms, however, may explain how personality change occurs. These mechanisms might have particularly important applied value for those wishing to promote certain personality attributes or modify existing ones (e.g., parents, teachers, or therapists). The first mechanism of personality change stems from the observation that individuals are responsive to contextual features of the situation, in other words, behavior changes in response to the salient cues, rewards, and punishments of a given setting. One possibility is that longterm exposure to specific contingencies may produce lasting personality changes. Life events such as marriage, parenthood, or military service may launch individuals into new
environments with clear and salient reward structures that produce enduring changes in personality. The other processes might involve more complicated social cognitive processes. Observing others might serve as the second process of personality change. The catalyst for this kind of personality change follows from the basic principles of social learning theory. For example, observing that a hardworking coworker is financially rewarded with a year-end bonus might promote imitation of that behavior to achieve a similar reward. Likewise, feedback from others may create personality changes. For example, having a daughter or son who looks to a parent as an important role model might help generate personality changes in the direction of increased maturity for that individual. A countervailing force is perhaps the tendency for individuals to process feedback from others in ways that confirm preexisting self-views. Last, deliberate selfreflection helps generate lasting personality changes. The idea that self-reflection and deliberation can lead to behavioral change is the essence of many psychotherapies. However, an important and perhaps even essential ingredient in these three processes of personality change beyond the responses to situational contingencies might be a strong initial motivation to change. Without this kind of motivation, the individual might not pay attention to particular models, process feedback from others in a way that can promote change, or otherwise invest effort in the process of self-change.
Conclusion The subfield of personality development is an exciting area of synergy that combines insights from behavioral genetics, clinical psychology, developmental psychology, personality psychology, and social psychology. There has been a dramatic accumulation of new knowledge in this area over the past few decades. Researchers have considerably more insight into how to conceptualize personality at multiple levels and how to describe and statistically model different types of personality stability and change. Key insights from the field of personality development are that personality exhibits a degree of coherence from childhood to adulthood. Nonetheless, there are characteristic changes in personality that seem to accompany aging that reflects increasing psychological maturity and the capacity to fulfill important adult roles. Likewise, individual differences in personality appear to become increasingly stable with age when viewed through the lens of rank-order stability such that childhood personality is probably more malleable than adult personality. Even so, personality changes can occur at all periods of the life span as there is no time in the human life span in which personality attributes are completely fixed. Ultimately, the most important message from the field of personality development is that personality stability and change result from dynamic processes that involve a complicated interplay or transaction between individuals and their environments.
See also: Big Five Model and Personality Disorders; Temperament and Individual Differences.
Personality Development
Further Reading Barrick MR and Mount MK (1991) The Big Five personality dimensions and job performance: A meta-analysis. Personnel Psychology 44: 1–26. Bouchard TJ Jr and Loehlin JC (2001) Genes, evolution, and personality. Behavior Genetics 31: 243–273. Canli T (2008) Toward a ‘molecular psychology’ of personality. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 311–327. New York: Guilford Press. Caspi A, Moffitt TE, Newman DL, and Silva PA (1996) Behavioral observations at age 3 years predict adult psychiatric disorders: Longitudinal evidence from a birth cohort. Archives of General Psychiatry 53: 1033–1039. DeYoung CG, Hirsh JB, Shane MS, Papademetris X, Rajeevan N, and Gray JR (2010) Testing predictions from personality neuroscience: Brain structure and the Big Five. Psychological Science 21: 820–828. Donnellan MB and Robins RW (2009) The development of personality across the life span. In: Corr PJ and Matthews G (eds.) Cambridge Handbook of Personality, pp. 191–204. New York: Cambridge University Press. Dyrenforth PS, Kashy DA, Donnellan MB, and Lucas RE (2010) Predicting relationship and life satisfaction in nationally representative samples from three countries: The relative importance of actor, partner, and couple similarity effects for personality traits. Journal of Personality and Social Psychology 99: 690–702. Ferguson CJ (2010) A meta-analysis of normal and disordered personality across the life span. Journal of Personality and Social Psychology 98: 659–667. Hampson SE and Friedman HS (2008) Personality and health: A lifespan perspective. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 770–794. New York: Guilford Press. Hampson SE and Goldberg LR (2006) A first large cohort study of personality trait stability over the 40 years between elementary school and midlife. Journal of Personality and Social Psychology 91: 763–779. McAdams DP and Pals JL (2006) A new Big Five: Fundamental principles for an integrative science of personality. American Psychologist 61: 204–217.
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McCrae RR and Costa PT Jr (1997) Personality trait structure as a human universal. American Psychologist 52: 509–519. Measelle JR, John OP, Ablow JC, Cowan PA, and Cowan CP (2005) Can children provide coherent, stable, and valid self-reports on the Big Five dimensions? A longitudinal study from ages 5 to 7. Journal of Personality and Social Psychology 89: 90–106. Miller JD and Lynam D (2001) Structural models of personality and their relation to antisocial behavior: A meta-analytic review. Criminology 39: 765–798. Nave CS, Sherman RA, Funder DC, Hampson SE, and Goldberg LR (2010) On the contextual independence of personality: Teachers' assessments predict directly observed behavior after four decades. Social Psychological and Personality Science 1(4): 327–334. Noftle EE and Robins RW (2007) Personality predictors of academic outcomes: Big Five correlates of GPA and SAT scores. Journal of Personality and Social Psychology 93: 116–130. Roberts BW and DelVecchio WF (2000) The rank-order consistency of personality traits from childhood to old age: A quantitative review of longitudinal studies. Psychological Bulletin 126: 3–25. Roberts BW, Walton KE, and Viechtbauer W (2006) Patterns of mean-level change in personality traits across the life course: A meta-analysis of longitudinal studies. Psychological Bulletin 132: 1–25. Roberts BW, Wood D, and Caspi A (2008) The development of personality traits in adulthood. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 375–398. New York: Guilford Press. Rothbart MK and Bates JE (1998) Temperament. In: Damon W (Series ed.) and Eisenberg N (Volume ed.) Handbook of Child Psychology: Vol. 3. Social, Emotional, and Personality Development, 5th edn., pp. 105–176. Hoboken, NJ: Wiley. Widiger TA and Smith GT (2008) Personality and psychopathology. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 743–769. New York: Guilford Press.
Glossary Cumulative continuity prinicple The observation that individual differences become more stable (or less malleable) with age. Dispositions Stable tendencies to think, feel, and behave in certain ways. Heterotypic stability Consistency in the same underlying personality disposition across development that may nonetheless demonstrate different behavioral manifestations at different ages. Homotypic stability Consistency in the same manifestations of personality across development. Intrinsic maturation hypothesis The perspective that changes in levels of personality traits in adulthood are generated by biological processes residing within the individual.
Personality refers to an individual’s stable tendencies to think, feel, and act in particular ways. The field of personality psychology focuses on understanding and assessing these individual differences in thoughts, feelings, and behavior. Accordingly, the subfield of personality development generally seeks to (1) describe patterns of stability and change in personality dispositions across the life span, (2) evaluate the influence of genetic and environmental factors on personality development, and (3) identify the processes that generate both consistency and change in personality dispositions from infancy to old age. Researchers typically address these types of questions using longitudinal designs in which the personality attributes of the same group of participants are assessed repeatedly across an appreciable span of development. Personality is most frequently assessed via self-reports and ratings of the participant by knowledgeable others (peers, parents, teachers); other commonly used assessment methods include observations of behavior in standardized situations; reaction times and other measures of cognitive processing; experience sampling; and a wide range of physiological measures. In this article, we outline three general levels at which personality can be conceptualized, discuss several types of personality stability and change, and then summarize the most recent findings and conclusions emerging from this exciting and interdisciplinary branch of psychology.
Considering Personality at Multiple Levels What are the building blocks of personality; that is, what are the fundamental ways in which individuals differ from each other? McAdams and Pals have proposed an integrative approach that conceptualizes personality at three levels of
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Life course hypothesis The perspective that adult personality changes result, in part, because of investment in adult social roles. Maturity principle The observation that personality trait changes in adulthood facilitate the fulfillment of adult roles (e.g., increases in agreeableness and conscientiousness). Mean-level stability Consistency in average levels for a given trait across developmental periods. Rank-order stability Consistency in the relative ordering of individuals for a given trait across developmental periods. Temperament The term usually refers to the dispositional attributes of young children. However, temperament can also generally refer to biologically based individual differences regardless of developmental period.
individual variability. The first level reflects those dispositional traits that reflect an individual’s general style of adjustment and approach to the social world. Although there are thousands of dispositional traits, personality psychologists generally agree that these traits can be usefully organized into five broad domains: extraversion (talkative, enthusiastic vs. quiet, reserved), agreeableness (kind, sympathetic vs. critical, quarrelsome), conscientiousness (reliable, self-disciplined vs. disorganized, careless), neuroticism (anxious, easily upset vs. calm, emotionally stable), and openness to experience or simply openness (imaginative, novelty seeking vs. uncreative, conventional). These trait domains (commonly referred to as the ‘Big Five’) are relatively consistent over the life course, generalize across cultures, and emerge in childhood. The Big Five have been linked to a variety of genes, neurotransmitters, brain structures, and neural activation patterns. These domains also predict a wide range of important life outcomes, including academic achievement, crime and delinquency, health and longevity, job performance, personality disorders, and relationship satisfaction. The other two levels in the framework of McAdams and Pals are characteristic adaptations and life narratives. Characteristic adaptations capture differences in motives and social cognitive processes such as the internal representations of key relationship partners (e.g., parents, romantic partners). These elements of personality are more contextualized than dispositional traits, and thought to be more responsive to situational forces. The third level captures those ongoing personal stories or narratives that individuals use to construct meaning from their lives. This level of individuality captures an individual’s ‘life story’ and is the bedrock of identity. Most research on personality development has focused on the level of core dispositions. In other words, more is known about the development of the Big Five domains than
Personality Development
characteristic adaptations and life stories. This will probably change in the future as researchers use large-scale longitudinal designs to study constructs at the other two levels of individuality. Nonetheless, this article focuses on dispositional traits because of the dearth of developmental research on the other two levels. However, it is important to keep in mind that there are other ways of characterizing individuals and these other levels of personality also have a developmental dimension.
Defining Different Types of Stability and Change Just how stable are personality dispositions across the life span? There are no easy ways to answer this question because there are different ways of conceptualizing and measuring stability and change in personality. A broad distinction is often made between homotypic and heterotypic stability (or continuity). Homotypic stability concerns the degree to which people express the same thoughts, feelings, and behaviors across time. This kind of stability focuses on the same manifestations of personality across time. In contrast, heterotypic stability refers to the consistency of the underlying personality traits that are theorized to have different observable manifestations at different ages. The investigation of heterotypic stability requires a conceptual understanding of the underlying personality disposition. That is, researchers must draw on a theory to specify how the same underlying personality disposition will appear to outside observers at different ages. The central issue is that many of the more salient behaviors associated with particular personality traits seem to change with development. A shy child might cling to his or her parent in the middle of a crowded room, whereas a shy adult might simply avoid large social gatherings altogether. Likewise, an aggressive toddler might bite classmates and throw temper tantrums, whereas an aggressive teen might use hostile words to insult classmates or use weapons to assault strangers. A theory about the nature of the underlying personality traits (shyness and aggressiveness, respectively) should be able to explain how these different surface manifestations reflect the same underlying personality dispositions. In contrast to heterotypic stability, the assessment of homotypic stability is less conceptual and more statistical. Homotypic stability concerns the evaluation of different kinds of change using the same measure of personality across time or across age groups. This broad category includes several specific types of stability and change. One type concerns the psychometric properties of the measurement instrument and is investigated under the term measurement stability. Two other types of stability and change are typically examined at the level of the sample and refer to particular personality attributes: mean-level stability and rank-order stability (also referred to as differential stability). Researchers can also investigate stability at the individual level by determining whether a particular individual increased or decreased in his or her absolute or relative trait standing over time. Investigations of measurement stability evaluate developmental changes in the measures used to assess personality attributes. This kind of stability is important because it helps researchers confirm that they are assessing the same psychological construct at different points in time (e.g., in childhood
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and adolescence). If measurement stability is not found, then researchers may wrongly infer that personality change has occurred when all that has happened is that the measure is tapping into a different construct across assessment occasions. Measurement properties can change even if the same items and item responses are used at two separate time points. A great deal of research in personality development focuses on mean-level stability, which refers to consistency in the average or typical level of a given trait across different developmental periods. One approach is to compare average scores for a personality attribute across different age groups, such as comparing the average level of shyness in samples of children, adolescents, and young adults. Results from these kinds of cross-sectional studies suggest that middle-aged adults (e.g., adults age 40–50) are higher in conscientiousness than teenagers. One problem with this research strategy is that age differences are conflated with birth cohort differences. Although middle-aged adults may actually be more conscientious than teenagers, it is also possible that individuals born in the 1950s are higher in conscientiousness than individuals born in the 1970s due to changes in cultural norms and expectations. The effects of age and birth cohort are inseparably confounded in a cross-sectional study. A better approach is to examine personality changes by following the same individuals over time using a longitudinal design. This method allows researchers to test whether average levels of conscientiousness increase for the same group of individuals as they mature from adolescence to adulthood. Investigations focused on average levels of personality attributes at different ages are sometimes called investigations of ‘normative’ personality differences because they provide information about the personality characteristics of the so-called ‘typical’ person at different stages of life. A concern is that average trends may obscure a great deal of individual variability in the way people change. Although conscientiousness may increase on average from adolescence to middle age, it is possible that it increases substantially in some individuals, in some only slightly, and in some it actually decreases. Given this possibility, some researchers prefer to focus on individual trajectories of personality development to determine how well each person in a sample follows the overall mean-level trends for the sample. Techniques for these analyses range from sophisticated growth curve models applied to multiwave data to fairly simple indices of real change, based on difference scores computed across two measurement occasions. Another popular area of research in personality development concerns the study of rank-order stability. A longitudinal design is required to investigate rank-order stability as it is typically measured using the correlation between the same personality measures administered at two time points but across an interval of sufficient length that will allow for the possibility of real personality change (e.g., more than a few months). These correlations are often called stability coefficients and they reflect the degree to which the relative ordering of individuals on a given trait is consistent over time. If researchers observe a high degree of rank-order stability for aggressiveness, it would mean that relatively aggressive adolescents tend to grow into relatively aggressive adults, regardless of any normative increases or decreases in aggressiveness that may co-occur with age. Rank-order stability is distinct from absolute stability
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because individuals may experience an overall decline or increase in absolute levels with age but nonetheless maintain their same position relative to others (e.g., there are large normative increases in height across development, but individuals generally maintain a similar rank ordering). A high degree of rank-order consistency is integral to the concept of a personality disposition. In summary, there are a number of conceptually and methodologically distinct ways of addressing questions about personality stability and change. This diversity requires the use of precise language to specify the exact type of consistency and change under investigation. Nonetheless, researchers strive to address all types of stability to provide a comprehensive picture of personality development. We now turn to summarizing basic findings about personality development across the life span.
Early Emerging Personality Attributes: Child Temperament Do emotionally reactive and difficult toddlers become aggressive adults? Do fearful infants become anxious adults? A key research issue in personality development concerns these questions about personality coherence or whether instantiations of individuality in young children are elaborated into adult personality traits. To be sure, individual differences are noticeable in even very young children. Some newborns are extremely fussy and difficult to soothe whereas other newborns are tranquil and easy to comfort. As newborns develop throughout infancy, they exhibit increasingly complex responses to the environment. Emotional reactions, ways of interacting with caregivers, and responses to the broader environment become more differentiated and patterned with age. At some point, these characteristics coalesce into the early emerging individual differences that are commonly referred to as attributes of childhood temperament. Mary Rothbart and John Bates provided one of the most widely used definitions of temperament: “constitutionally based individual differences in emotional, motor, and attentional reactivity and self-regulation.” An important element of this definition is the emphasis on dimensions of individuality that are thought to be rooted in biology. However, temperament researchers acknowledge that nearly all early emerging individual differences are affected by life experiences as well as by genetically influenced tendencies and other physiological factors. A second important element of this definition is an emphasis on emotional processes as many of the separate dimensions of temperament reflect individual differences in the functioning of affective systems that motivate behavior in either an approach or avoidance fashion. As with the research on the structure of adult personality traits that seeks to identify a set of basic domains that can be integrated into a hierarchical structure ranging from broader to narrower dispositions, researchers also seek to identify the basic dimensions and organizing structure of childhood temperament. One prominent model for childhood temperament identifies three broad dimensions – positive emotionality, negative emotionality, and constraint versus disinhibition. Positive emotionality captures the tendencies to approach the environment and engage in interactions with others
(i.e., extraversion). Negative emotionality captures the tendencies to become distressed, experience aversive emotions, and feel threatened (i.e., neuroticism). Constraint versus disinhibition captures the ability to exercise control over impulses and direct behavior toward achieving longer term goals (i.e., conscientiousness). A largely complementary approach classifies temperamental dimensions using childhood analogs of the Big Five dimensions of adult personality – extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience – to organize the dimensions of childhood temperament. Indeed, some researchers actually consider the Big Five to be the dimensions of temperament. These domains are evident in adolescents and even in children as young as 5 years of age. The one caveat is that openness to experience may not have a clear parallel in childhood temperament. The difficultly in linking openness to experience with childhood temperament is perhaps not surprising given that openness seems to have the least consistent link with neurological systems in the brain. As it stands, there is evidence for a connection between childhood temperament and adult personality. A complication is that longitudinal research focused on the same dispositions from childhood to adulthood is fairly rare. This should change as more and more longitudinal studies are designed to explicitly address this important question. One of the most recent and impressive examples of personality coherence comes from a study of the Hawaii Personality and Health Cohort. Investigators of this project have followed roughly 2404 individuals from the time they were elementary school children in the early 1960s to the present. A team of investigators video recorded a subset of these individuals when they were middle-aged adults. These recordings were then coded for a diverse range of personality attributes by trained coders. There was an appreciable correlation between the ratings of the individuals made by their elementary school teachers and the observer ratings of those same individuals at midlife. Individuals rated as talkative by teachers in elementary school developed into middle-aged adults who were rated as socially dominant and assertive by observes. Individuals rated as able to cope with new situations and face uncertainty were rated as cheerful and self-confident as middle-aged adults. A key message from this study is that there is a meaningful personality coherence from childhood to middle age. In a similar vein, researchers studying a cohort of individuals born in New Zealand have found meaningful associations between ratings of 3-year-old children made by clinical interviewers and adult outcomes at age 21. Children who were rated as being irritable and impulsive at age 3 were more likely to be dependent on alcohol and to have been convicted of a violent crime by age 21. The fact that there is a connection between preschool attributes and problems with alcohol and violence during early adulthood is impressive evidence for the coherence of traits related to difficulties with impulse control. This work also points to personality coherence across development even when considering the personality attributes of very young children. All in all, efforts to integrate childhood temperament with adult personality are progressing as researchers converge on a set of basic dimensions that are relevant for adaptation across the life span. This effort at integration will take some time,
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however, because it will be years and even decades before participants in newly initiated studies mature from children into adults. Nonetheless, efforts to unify research on childhood temperament and adult personality represent an exciting area of synergy between developmental psychology and personality psychology that may help to curb the ‘jangle fallacy’ that permeates psychological science (i.e., if two constructs have different names then they must be different).
Mean-Level and Rank-Order Stability of the Big Five Across the Life Span What are the patterns of normative personality development? What is the pattern of rank-order stability across the life span? Summarizing research on these topics has been greatly facilitated by a number of meta-analyses that were conducted in the last decade. A meta-analysis is a statistical approach for summarizing research literatures and essentially involves averaging the results from all available studies. This method permits researchers to quantify findings across the entire research literature and is perhaps optimal to narrative reviews, which simply provide qualitative impressions of previous work. A meta-analysis by Roberts, Walton, and Viechtbauer provided a summary of average levels of the Big Five traits using data from 113 longitudinal samples involving 50 120 participants ranging in age from adolescence through old age. These researchers divided the extraversion domain into two facets: social dominance (traits related to independence and dominance) and social vitality (traits related to positive affect, activity level, and sociability). Average levels of social vitality tended to be fairly flat across the life span, although there was a slight spike upward from adolescence to young adulthood followed by a plateau until the mid-50s when there was a slight decline. Social dominance, on the other hand, showed a more pronounced trend such that there was a consistent absolute increase from adolescence to the early 30s where mean levels remained consistent until the mid-50s, after which the lack of studies precluded further analyses. Agreeableness and conscientiousness showed gradual increases in absolute scores across the life span whereas neuroticism showed gradual decreases. Finally, openness showed a mean-level increase from adolescence to young adulthood and then mean levels remained constant until the mid-50s when it started to show a slight decline in average levels. One of the more interesting results that emerged from this meta-analysis concerned the adolescent period. Contrary to the popular belief that adolescence involves tumultuous changes in personality, the Roberts et al. meta-analysis demonstrated that the largest mean-level changes in personality occur during the young adult years (i.e., the 20s). This is the phase in the life span when individuals assume the roles of worker, committed romantic partner, and in many cases, parent and caregiver. Furthermore, it is easy to see how increasing levels of agreeableness and conscientiousness and decreasing levels of neuroticism facilitate the successful enactment of the roles of worker, parent, and committed romantic partner. Thus, average levels of traits change in ways that coincide with the time in the life span during which individuals assume mature social roles, a pattern referred to as the maturity principle of adult personality development.
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In summary, the available data indicate that average levels of agreeableness and conscientiousness increase with age whereas average levels of extraversion (in the aggregate), neuroticism, and openness decline with age. There are two dominant explanations for these mean-level differences in the Big Five domains across the life span. The intrinsic maturational position holds that normative age-related changes in personality are driven by unfolding biological processes related to aging whereas the life course position posits that changes stem from investment in particular social roles and the life experiences that accompany these roles. Researchers are currently debating which perspective has the most empirical support. One of the complicating factors is that critical tests of these two explanations are nearly impossible because experimental manipulations of either biological factors or important social roles are neither ethical nor feasible. At least two different meta-analyses have investigated rankorder stability across the life span. Roberts and DelVecchio examined test–retest correlations from 152 longitudinal studies and found that the rank-order stability of personality increases across the life span, ranging from a low around 0.30 in childhood to a high of 0.70 in late adulthood. This pattern generally held for men and women and for all five of the Big Five traits. A more recent meta-analysis by Ferguson reached similar conclusions, although in his analysis rank-order stability reached a plateau earlier in development than in the Roberts and DelVecchio analysis (perhaps because he corrected the rank-order stability estimates for measurement error). The finding that the rank-order stability of personality increases from childhood to adulthood is known as the cumulative continuity principle of personality development – that is, personality becomes increasingly stable with age (when viewed through the lens of rank-order stability). This naturally raises questions as to why rank-order stability increases with age. Lower stability is expected when individuals respond to experiences differently or experience personality-altering environments at different times. The transition from childhood to adolescence involves rapid maturational changes, shifting societal demands, exploration of new identities and roles, and initiation of new peer and romantic relationships. These changes may impact individuals in relatively unique ways, thus shifting their relative ordering on a trait and thereby reducing stability coefficients. In contrast, the transition to adulthood is accompanied by fewer maturational changes and social transitions that begin to stabilize. Likewise, a hallmark of adulthood is the increased ability to select environments consistent with individual dispositions. These broad developmental considerations may explain the cumulative continuity principle. Indeed, researchers are now moving beyond simply documenting patterns of mean-level and rank-order stability to testing hypotheses about the underlying mechanisms that produce personality consistency and change.
What Mechanisms Account for Personality Stability and Change? What specific mechanisms account for the stability of personality over time and, conversely, what account for change? Contemporary research suggests that personality stability and change result from complicated transactions between
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persons and situations. Three processes in particular might promote stability in personality by producing a correspondence between personality traits and characteristics of the social environment. First, personality traits ‘draw out’ or otherwise evoke corresponding responses from the social environment. This matching between the underlying dimension and the environmental response or reaction may reinforce both the disposition and the individual’s social ecology. This process would tend to promote personality continuity. For example, individuals who are aggressive may evoke more hostile responses from classmates and coworkers. These hostile responses may then accentuate the initial tendency toward aggressiveness. In short, it seems as if many individual dispositions generate responses in social environments which end up reinforcing those very dispositions. Second, personality traits shape how people interpret social situations that can have real consequences for behavior and its effects. The same objective environment, such as a cocktail party, may prove stimulating and exciting to an extraverted individual but terrifying to an introverted person. These different construals of the same objective environment might facilitate self-fulfilling prophecies. The scared introvert might act awkward and stand-offish to fellow party guests, thereby generating unpleasant and strained interpersonal encounters. The upshot is that this process would also tend to reinforce initial personality dispositions. Third, personality traits can influence the settings that individuals select and create for themselves. One of the consequences of human agency and autonomy is that individuals have the freedom to seek out, modify, and even create environments that are consistent with their individual characteristics. The characteristics of individuals and the characteristics of their social situations are therefore correlated. For example, what people do for a living and how they structure their environments may reflect their personalities. These social contexts may then help to maintain the personality characteristics that were initially responsible for the selection processes in the first place. Individuals who are outgoing and sociable may choose careers that fit well with these tendencies and shun solitary occupations with limited potential for social interaction. Such a career may enhance and sustain these extraverted tendencies. The upshot of these three mechanisms is that many life experiences serve to deepen and intensify the personality characteristics that were partially responsible for the environmental or social experiences in the first place. This is known as the corresponsive principle of personality development. The principle would naturally promote personality consistency across developmental periods. A different set of mechanisms, however, may explain how personality change occurs. These mechanisms might have particularly important applied value for those wishing to promote certain personality attributes or modify existing ones (e.g., parents, teachers, or therapists). The first mechanism of personality change stems from the observation that individuals are responsive to contextual features of the situation, in other words, behavior changes in response to the salient cues, rewards, and punishments of a given setting. One possibility is that longterm exposure to specific contingencies may produce lasting personality changes. Life events such as marriage, parenthood, or military service may launch individuals into new
environments with clear and salient reward structures that produce enduring changes in personality. The other processes might involve more complicated social cognitive processes. Observing others might serve as the second process of personality change. The catalyst for this kind of personality change follows from the basic principles of social learning theory. For example, observing that a hardworking coworker is financially rewarded with a year-end bonus might promote imitation of that behavior to achieve a similar reward. Likewise, feedback from others may create personality changes. For example, having a daughter or son who looks to a parent as an important role model might help generate personality changes in the direction of increased maturity for that individual. A countervailing force is perhaps the tendency for individuals to process feedback from others in ways that confirm preexisting self-views. Last, deliberate selfreflection helps generate lasting personality changes. The idea that self-reflection and deliberation can lead to behavioral change is the essence of many psychotherapies. However, an important and perhaps even essential ingredient in these three processes of personality change beyond the responses to situational contingencies might be a strong initial motivation to change. Without this kind of motivation, the individual might not pay attention to particular models, process feedback from others in a way that can promote change, or otherwise invest effort in the process of self-change.
Conclusion The subfield of personality development is an exciting area of synergy that combines insights from behavioral genetics, clinical psychology, developmental psychology, personality psychology, and social psychology. There has been a dramatic accumulation of new knowledge in this area over the past few decades. Researchers have considerably more insight into how to conceptualize personality at multiple levels and how to describe and statistically model different types of personality stability and change. Key insights from the field of personality development are that personality exhibits a degree of coherence from childhood to adulthood. Nonetheless, there are characteristic changes in personality that seem to accompany aging that reflects increasing psychological maturity and the capacity to fulfill important adult roles. Likewise, individual differences in personality appear to become increasingly stable with age when viewed through the lens of rank-order stability such that childhood personality is probably more malleable than adult personality. Even so, personality changes can occur at all periods of the life span as there is no time in the human life span in which personality attributes are completely fixed. Ultimately, the most important message from the field of personality development is that personality stability and change result from dynamic processes that involve a complicated interplay or transaction between individuals and their environments.
See also: Big Five Model and Personality Disorders; Temperament and Individual Differences.
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Further Reading Barrick MR and Mount MK (1991) The Big Five personality dimensions and job performance: A meta-analysis. Personnel Psychology 44: 1–26. Bouchard TJ Jr and Loehlin JC (2001) Genes, evolution, and personality. Behavior Genetics 31: 243–273. Canli T (2008) Toward a ‘molecular psychology’ of personality. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 311–327. New York: Guilford Press. Caspi A, Moffitt TE, Newman DL, and Silva PA (1996) Behavioral observations at age 3 years predict adult psychiatric disorders: Longitudinal evidence from a birth cohort. Archives of General Psychiatry 53: 1033–1039. DeYoung CG, Hirsh JB, Shane MS, Papademetris X, Rajeevan N, and Gray JR (2010) Testing predictions from personality neuroscience: Brain structure and the Big Five. Psychological Science 21: 820–828. Donnellan MB and Robins RW (2009) The development of personality across the life span. In: Corr PJ and Matthews G (eds.) Cambridge Handbook of Personality, pp. 191–204. New York: Cambridge University Press. Dyrenforth PS, Kashy DA, Donnellan MB, and Lucas RE (2010) Predicting relationship and life satisfaction in nationally representative samples from three countries: The relative importance of actor, partner, and couple similarity effects for personality traits. Journal of Personality and Social Psychology 99: 690–702. Ferguson CJ (2010) A meta-analysis of normal and disordered personality across the life span. Journal of Personality and Social Psychology 98: 659–667. Hampson SE and Friedman HS (2008) Personality and health: A lifespan perspective. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 770–794. New York: Guilford Press. Hampson SE and Goldberg LR (2006) A first large cohort study of personality trait stability over the 40 years between elementary school and midlife. Journal of Personality and Social Psychology 91: 763–779. McAdams DP and Pals JL (2006) A new Big Five: Fundamental principles for an integrative science of personality. American Psychologist 61: 204–217.
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McCrae RR and Costa PT Jr (1997) Personality trait structure as a human universal. American Psychologist 52: 509–519. Measelle JR, John OP, Ablow JC, Cowan PA, and Cowan CP (2005) Can children provide coherent, stable, and valid self-reports on the Big Five dimensions? A longitudinal study from ages 5 to 7. Journal of Personality and Social Psychology 89: 90–106. Miller JD and Lynam D (2001) Structural models of personality and their relation to antisocial behavior: A meta-analytic review. Criminology 39: 765–798. Nave CS, Sherman RA, Funder DC, Hampson SE, and Goldberg LR (2010) On the contextual independence of personality: Teachers' assessments predict directly observed behavior after four decades. Social Psychological and Personality Science 1(4): 327–334. Noftle EE and Robins RW (2007) Personality predictors of academic outcomes: Big Five correlates of GPA and SAT scores. Journal of Personality and Social Psychology 93: 116–130. Roberts BW and DelVecchio WF (2000) The rank-order consistency of personality traits from childhood to old age: A quantitative review of longitudinal studies. Psychological Bulletin 126: 3–25. Roberts BW, Walton KE, and Viechtbauer W (2006) Patterns of mean-level change in personality traits across the life course: A meta-analysis of longitudinal studies. Psychological Bulletin 132: 1–25. Roberts BW, Wood D, and Caspi A (2008) The development of personality traits in adulthood. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 375–398. New York: Guilford Press. Rothbart MK and Bates JE (1998) Temperament. In: Damon W (Series ed.) and Eisenberg N (Volume ed.) Handbook of Child Psychology: Vol. 3. Social, Emotional, and Personality Development, 5th edn., pp. 105–176. Hoboken, NJ: Wiley. Widiger TA and Smith GT (2008) Personality and psychopathology. In: John OP, Robins RW, and Pervin LA (eds.) Handbook of Personality: Theory and Research, 3rd edn., pp. 743–769. New York: Guilford Press.