Personality Development in Adulthood Research Paper

In this research paper we define and examine the nature of personality in adulthood and old age from multiple perspectives. We first provide a historical overview of theoretical approaches, and then we present the current major theoretical perspectives in the field, including a discussion of relevant findings from key empirical studies. We examine trait approaches (e.g., McCrae & Costa, 1987; Roberts & DelVecchio, 2000) to the study of personality with a focus on rank-order and mean-level consistency, as well as individual differences in personality and how these differences shape the experiences of older adults. We also examine theories with a life-span approach to personality such as stage theories (e.g., Erikson, 1963; Levinson, 1978) and contextual models that incorporate person-environment interactions (e.g., Caspi, 1987; Helson, 1984; Neugarten & Gutmann, 1958). The phenomenological approach to personality is also relevant to the study of adulthood and old age. Some of the major findings regarding subjective personality change (e.g., Fleeson & Baltes, 1998) and personality as a predictor of later life outcomes (e.g., Caspi, 1987) are discussed. We also examine specific aspects of the self-construct such as identity (e.g., Whitbourne, 1987), self-efficacy and control (e.g., Bandura, 1997; Lachman & Weaver, 1998), well-being (e.g., Ryff, 1989), and emotions and coping (e.g., Lazarus & Folkman, 1984). Finally, we summarize the current state of the adult personality literature and make suggestions for the direction of future research.

Historical Background

The view of development as a lifelong process can be traced to the eighteenth and nineteenth century philosophers Quetelet, Carus, and Tetens (Baltes, 1983). However, psychological development beyond young adulthood was not embraced by those studying human behavior until much later. Early theorists conceptualized development as a phenomenon unique to the early years of life, suggesting that beyond this point development was virtually nonexistent. This popular sentiment was epitomized in the classic statement by William James when he wrote that by the age of 30, character is “set like plaster, and will never soften again” (W. James, 1890, p. 121). Others, such as Freud, believed that psychological maturity was reached at an even younger age. According to Freud’s psychoanalytic theory, personality is determined at some time during middle childhood. Any observation of psychological change after this point in life was seen as the result of early experiences and not of continued development. The child-centric view of development has its roots in the work of Rousseau (1762/1948) and has been reinforced by the writings of Freud (1905) and other preeminent theorists such as Piaget (1936/1974) and Bowlby (1982).

A life-span view of personality development emerged in the early twentieth century with work by C. Jung, C. Buhler, G. Stanley Hall, and E. Erikson. The most well known of these perspectives are Jung’s (1933) psychoanalytic theory, which dealt primarily with issues of balancing polarities such as masculinity and femininity throughout adulthood, and Erikson’s (1963) psychosocial model of ego development, which expanded Freud’s theory to include developmental stages throughout the life-span, including old age.

Advanced primarily by Erikson’s psychosocial theory of lifelong development and by early empirical studies conducted by Neugarten and Gutmann (1958), which support the idea of change in later adulthood, research and theory have expanded beyond the child-centric approach to psychological development (e.g., Field & Millsap, 1991; Loevinger, 1976; Vaillant, 1977). A recent surge of theoretical conceptualizations and empirical investigations has culminated in a sizable literature that adopts the view of personality as a lifelong process of development (e.g., Baltes, 1987; Baltes et al., 1998; Featherman & Lerner, 1985; Lachman & Baltes, 1994; R. M. Lerner, 1976). The life-span approach is a useful perspective from which to study personality development in later adulthood. First, through a comprehensive host of theories, the life-span approach represents the dynamic complexities inherent in the experiences of middle-aged and older adults. In addition, this approach integrates sources of variation such as sociocultural, historical, and genetic factors that are especially important to consider when examining the trajectory of development into adulthood and old age.

Furthermore, the advancement of powerful methodological techniques has provided developmentalists with the tools necessary for effectively modeling personality and the self in later years within the context of the life-span perspective (e.g., Schaie, 1996). We are no longer restricted to the investigation of normative individual differences; longitudinal research designs and sophisticated statistical techniques provide the opportunity to model intra-individual change so that complex patterns of development throughout the life span can be explored. With longitudinal designs and state-of-theart methodological techniques, confounding factors such as age and cohort effects can be teased apart and contextual qualities such as socioeconomic status can be tested for the efficacy of their mediational effects. The adoption of a lifespan approach for the study of personality facilitates the investigation of stability and change well into old age.

Theoretical Perspectives on Personality

The research on personality development in adulthood and aging has been guided by a variety of theoretical perspectives and conceptual models. For example, some investigations employ contextual models that emphasize the life-span approach. These studies focus on the dynamic interaction between social and historical contexts on personality patterns (Schaie & Hendricks, 2000). Other studies utilize trait and stagetheoriesofdevelopment.Theunderlyingpremiseoftrait theory (e.g., Costa & McCrae, 1988; Roberts & DelVeccho, 2000) is that personality attributes are formed early in life and that they exhibit consistency across adulthood. In contrast, stage theories (e.g., Erikson, 1963; Levinson, 1977) are built on the concept that personality continues to evolve throughout adulthood according to the epigenetic principle (see R. M. Lerner, 2002); each stage unfolds from its previous stage in a predetermined, sequential way. Human personality in adulthood and old age is a complex, multifaceted phenomenon that is best represented using multiple perspectives.

Trait Theories

Perhaps the most well-known perspective on personality is the trait view (Costa & McCrae, 1984). A trait is commonly described as an enduring personality characteristic that remains stable over time and is consistent across situations. Purportedly, roots of traits can be traced to genetic components, and their expression is manifested in early temperament (Bouchard, 1997; but see R. M. Lerner, 2002, for a contrasting point of view based on life-span developmental systems theory or Baltes et al., 1998). From the perspective of trait theory, personality can be defined as the expression of these sustaining inherent attributes.

The Big Five

Although several trait taxonomies have been proposed to delineate the structure of personality, the five-factor model known as the Big Five is the most widely applied to adulthood and aging. The five-factor model includes the following dimensions: neuroticism, extroversion, openness to experience, agreeableness, and conscientiousness. There is widespread support for the Big Five using multiple measures including the California Q-Set (McCrae, Costa, & Busch, 1986) and the NEO Personality Inventory (McCrae & Costa, 1987), which have demonstrated convergent and discriminant validity for self-reports and peer and spouse ratings.

Stability and Change

The preponderance of empirical research points to rank-order stability across time on the trait dimensions (e.g., Costa & McCrae, 1988; Haan et al., 1986; Roberts & DelVecchio, 2000). This implies that the ordinal position of individuals within a group remains the same relative to other individuals on trait dimensions over time. For example, using the California Q-sort (see Block, in collaboration with Hann, 1971), Haan et al. (1986) found substantial stability over 50 years (i.e., ages 5–62) in the Oakland Growth and Guidance studies. With one exception occurring in the component of “warm/hostile” during the transition from late adolescence to early adulthood, all test-retest, interval-specific correlations were positive across the life span and into old age.

Support for the stability position comes largely from studies based on the Baltimore Longitudinal Study of Aging. This ongoing, large-sample survey of relatively healthy, highly educated individuals was begun in 1958 and includes individuals from across adulthood ranging in age from the late 20s into the 90s. When analyzed longitudinally, findings from these studies demonstrate remarkable stability on self-reports of personality behavior across approximately 30 years of adulthood (e.g., Costa & McCrae, 1984, 1988; McCrae & Costa, 1985, 1987, 1994). Converging evidence for these findings comes from peer ratings on personality dimensions (Costa & McCrae, 1988; McCrae & Costa, 1987). Across a 6-year span, consistency in the ratings of personality traits reported by participants’ spouses was also revealed.

Meta-analyses conducted by Roberts and DelVecchio (2000) provide a more complicated picture with less definitive answers regarding stability. Their examination of 124 longitudinal studies revealed high levels of rank-order consistency on personality trait dimensions over time, but it was not until the period between middle and older adulthood (i.e., ages 50–59 and 60–73) that trait consistency stabilized, a finding that conflicts with the popular notion that trait stability peaks by the age of 30 (e.g., Costa & McCrae, 1988; W. James, 1890; McCrae & Costa, 1994).

It is important to note that rank order stability does not imply stability at the mean level. Although there is strong evidence for trait consistency when considering rank order, there is also evidence from longitudinal investigations for normative, mean-level changes in some of the traits across time and suggestive support from cross-sectional studies for age differences (e.g., McCrae & Costa, 1994; Haan et al., 1986). For example, Roberts and DelVecchio (2000) reported that although high levels of rank-order stability were found in their meta-analysis, the estimates of between-age-group consistency were not high enough to argue that personality dimensions are impervious to change. This conclusion is supported in the findings from other studies that examine meanlevel change in personality traits. For example, McCrae and Costa (1994) reported that compared to younger adults, older adults reported lower levels of extroversion, particularly activity and thrill-seeking, neuroticism, and openness to experience. As a result, older adults were less anxious and selfconscious but also less likely to explore new horizons.

In a 14-year longitudinal study of older adults, Field and Millsap (1991) found an increase in the dimension of agreeableness between ages 69 and 83. Similarly, Haan et al. (1986) noted that in the Oakland Growth and Guidance studies substantial changes in personality continued to occur into later adulthood. Theses authors concluded that with increased age, people confront greater experiential change that, in turn, can lead to a change in the expression of personality. In contrast, other researchers explain consistency in personality dimensions across time as due to fewer novel experiences confronted by the older adult (Glenn, 1980).

Further suggestive evidence for mean-level differences in personality across adulthood comes from the study of Midlife in the United States (MIDUS; John D. and Catherine T. MacArthur Foundation Research Network on Successful Midlife Development) using trait attribute ratings. Findings from this nationally representative cross-sectional study revealed significant mean age-group differences between young, middle-aged, and older adults on some of the Big Five traits (Markus & Lachman, 1996). Specifically, results indicated that scores on agreeableness were highest in the group of older adults, whereas scores on openness to experience and neuroticism were lowest among the older adults. Conscientiousness was highest in the midlife group.

It appears from the discussion of rank-order versus meanlevel consistency in trait dimensions that to a large degree the findings vary based on the type of question asked and the type of methodology utilized to answer the question (see Caspi & Roberts, 1999). Specifically, among the studies reported here, those investigating rank order across time by examining testretest correlations largely demonstrated stability, whereas those interested in between-age-group comparisons revealed mean-level differences on some personality dimensions. Moreover, mean-level differences were revealed in both longitudinal studies that examined intra-individual change in personality dimensions over time and cross-sectional studies that explored differences between age/cohort groups. For example, intra-individual change over time in average agreeableness was demonstrated longitudinally (Field & Millsap, 1991), with supporting cross-sectional evidence revealing age/cohort differences favoring older adults (Markus & Lachman, 1996). Further, between-group differences in neuroticism and openness to experience were found in cross-sectional studies with older adults showing lower levels in these personality traits than younger groups (McCrae & Costa, 1994). Although the issue of stability versus change in personality development across the life span continues to be an interesting topic of study, the focus of personality research has shifted to the potentially more important question of how these stable personality styles impact the course of aging (Lachman, 1989).

Personality Dimensions as Antecedents

Personality attributes are believed to play a major role in the nature and course of development in adulthood and old age (Lachman & Bertrand, 2001). For example, on one hand, it is possible that certain personality styles such as neuroticism may drive individuals toward risk-taking behaviors that could negatively influence their life course and health status in older adulthood. On the other hand, personality styles such as conscientiousness may direct individuals to practice protective health-behaviors that could delay morbidity and mortality in the later adult years (Schwartz et al., 1995; Friedman et al., 1995). Longitudinal evidence from the Terman Life Cycle Study of Children with High Ability supports the hypothesis that childhood personality dispositions predict later life outcomes. Findings demonstrated that certain childhood and early adult personality traits such as conscientiousness predict increased longevity (Schwartz et al., 1995). The authors concluded that conscientious children were healthier and lived longer because they were more likely to adopt healthy self-care patterns that would prevent or delay illness. In addition, they were more likely to avoid dangerous situations that would put their health at risk. The issue of how the course of aging varies as a function of personality attributes will be addressed in greater detail in a subsequent section of this research paper.

The trait view assumptions of individual differences in personality and stability across adulthood are in direct contrast to stage views of personality development. In the following section we examine some of the predominant stage models of psychological development giving particular attention to the later stages that include adulthood and old age.

Stage Theories

Whereas trait theories assume that personality characteristics are acquired early in life and demonstrate life-long stability (e.g., Costa & McCrae, 1988), stage theories are characterized by the premise of continued development and change across the life span (e.g., Erikson, 1950). In general, stage models divide the life span into periods loosely tied to chronological age to describe normal, sequential patterns of developmental change (Reese & Overton, 1970). According to stage theory, each period is associated with a particular developmental task. When successfully straddled, it provides the foundation from which to confront the challenge of the next stage (Havighurst, Neugarten, & Tobin, 1968). Based on the tenets of stage theory, personality can be defined as a lifelong process of maturity in which internal forces interact with external forces through a stepwise series of stages to produce outward behavior.

Erik H. Erikson

Several stage models of development that include adulthood and old age have been theorized (e.g., Erikson, 1950; Vaillant, 1977; Levinson, 1977; Loevinger, 1976); however, perhaps the most preeminent and influential is Erik H. Erikson’s (1950) eight-stage psychosocial model of development. An extension of Freud’s theory of psychosexual development, Erikson’s model has two primary advantages over Freud’s. First, it includes a life-span view of development, second, it incorporates societal and cultural influences on development. Freud’s theory describes personality as relatively fixed by age 5. Any change in behavior beyond that point is viewed as the result of early childhood influences and not continued development. In addition, Freud assigned primary importance to largely unconscious intrapsychic processes in determining personality development. Erikson expanded on Freud’s theory by creating a developmental model in which the ego evolves through the dynamic interaction between internal and external forces throughout the entire life course.

According to Erikson’s model, there are eight stages of psychosocial development that are biologically hardwired to unfold in a predetermined, sequential manner. Following his version of the epigenetic principle, Erikson believed that the ego evolves out of this preprogrammed schedule in stages in which different components of the ego have the opportunity to develop during specific times. Erikson proposed that each of the eight stages is marked by a tension or crisis between two opposing challenges (e.g., generativity vs. stagnation). The crises are resolved through a dynamic interaction between inner ego strength that evolves and develops from the previous stage and outer societal and cultural demands. The result of each crisis is a strengthened or weakened ego that, in turn, becomes the basis for resolving the crisis in the next succeeding stage. Development continues to evolve in this manner throughout the life span with later stages built on the foundation of previous ones. The possibility of complete psychosocial maturity is acquired only in later adulthood after all eight stages have been positively resolved (i.e., ego integrity is achieved). Healthy psychosocial development may be comprised, however, if an individual progresses to a stage without the successful resolution of a task at a previous stage. In optimal development the sequence of stages is followed precisely with each respective crisis resolved successfully. However, certain environmental experiences can send an individual off course, thereby changing the timing and pattern of development and hindering the successful resolution of a successive stage. A developmental course influenced in such a way will result in a weakened ego and negatively impact present and future development (Whitbourne, Zuschlag, Elliot, & Waterman, 1992).

Relevant to adulthood, Erikson proposed three distinct stages in which the individual must confront a crisis between opposing forces: intimacy versus isolation in young adulthood, generativity versus stagnation in midlife, and ego integrity versus despair in old age. In young adulthood, after achieving a sense of ego identity, the challenge set forth in Erikson’s theory is to establish a relationship with a significant other without losing one’s own sense of self. Erikson theorized that middle-aged adults reach a point in their ego development at which they must struggle between assuming a sense of responsibility toward the next generation (i.e., generativity) and maintaining a position of self-absorption (stagnation). As already discussed, each stage is built on the strength of the ego as it evolves from the resolution of the previous stage. As a result, the midlife adult whose ego was strengthened by successfully achieving intimacy as opposed to isolation as a young adult is more likely to resolve the midlife stage toward generativity. This individual will be trusting and willing to propagate his or her skills and knowledge to the next generation. Although generativity is commonly thought of as the adoption of a parenting role, it can also be carried out via other roles such as a teacher, mentor, or coach. Generativity is reflected in any activity in which the adult assumes the responsibility for guiding the next generation in a productive or creative way (Erikson, 1963; McAdams, 2001). Erikson proposed that the virtues of caring, giving, sharing, and teaching develop out of the need to nurture and direct the next generation.

In contrast, the midlife adult who progressed through the young adult stage with an imbalance toward isolation will have a weakened ego that is likely to inhibit the establishment of generativity. In midlife this adult will be selfcentered and self-absorbed and lack interest in training or guiding the next generation. The resultant imbalance toward stagnation will further weaken the ego and render it unable to carry out a successful resolution of the crisis in the final stage of development.

The final stage of psychosocial development proposed by Erikson (1963) is that of ego integrity versus ego despair. As individuals age, there is an increasing awareness of the limits of time—a realization of inevitable, impending death. The effect of this awareness is to inspire older adults to reflect on how they lived their lives. Older adults who look back with satisfaction and contentment and an acceptance of both the negative and positive aspects of their lives are at peace and, in this way, are prepared to accept the inevitability of death. These adults have integrated the past and present and have embraced the importance and meaningfulness of their lives; they have achieved ego integrity. On the other hand, older adults who have not resolved the past, who experience anxiety about making amends for prior mistakes, and who feel the need to complete unfinished business are not ready to accept the inevitability of death. In fact, these adults may fear or dread their impending death and view it as another in a series of failures and disasters that have comprised the quality of their lives. These adults have failed to find purpose and meaning in their lives and have not achieved ego integrity; rather, they are in a state of ego despair (Erikson, 1963; Ryff, 1989).

Although Erikson’s theory emphasizes the resolution of tasks that are stage specific and unfold in a preprogrammed sequence, there is also recognition that it is possible to revisit tasks of earlier stages throughout the life span. In adulthood, driven by an urge to establish a sense of integrated wholeness, adults may strive to reconcile earlier unresolved crises. In other words, although the adult has passed through the stages in a preprogrammed, sequential manner, the opportunity to go back to a stage that was not successfully resolved in order to reprocess the crisis exists. The issues associated with each stage are also prevalent throughout life even though they may be most salient at a given time in the life course.

Erikson has been credited for being among the first theorists to propose a model of lifelong development and to integrate both inner forces and external circumstances in determining the fate of ego development. Indeed, his work has inspired the conceptualization and publication of several other stage theories, such as those by Vaillant (1977), Levinson (1977), and Loevinger (1976). However, limitations to Erikson’s theory should be addressed. First, it has been criticized for being based on highly educated males and Western cultural norms without an acknowledgment that women and non-Western cultures may have different developmental trajectories (Gilligan, 1982; Kahn, Zimmerman, Cskiszentmihalyi, & Getzels, 1985). Although Erikson’s theory should be cautiously applied to more diverse groups, there is some evidence for its generalizability to less privileged samples (Vallaint & Milofsky, 1980).

Asecond criticism of Erikson’s psychosocial theory is that although it is a viable model of development, it is very difficult to quantify and measure. As a result, few empirical studies have been conducted to test the theory. The most comprehensive investigation to date is the Rochester study conducted by Whitbourne and colleagues (Whitbourne & Waterman, 1979; Whitbourne et al., 1992). This crosssequential, longitudinal study has followed several groups of graduates from the University of Rochester beginning in 1966 with the oldest cohort entering midlife (i.e., age 42) in the most recent analysis (1988). Data that include older adults are not available, nor are they available from a range of ages in midlife. However, based on the sample tested, findings from this study provide moderate support for the validity of Erikson’s final stages of development. The college-aged cohort scored lower than the older cohorts on measures of generativity (Stage 7) and ego integrity (Stage 8). In other words, as proposed by Erikson, it appears as though these developmental tasks are not confronted until later adulthood. However, to make such a statement definitively, it will be necessary to follow this sample throughout midlife and into old age. Vaillant and Milofsky (1980) also tested and found support for the invariant sequence of Erikson’s stages in adulthood.

Regardless of the limitations of Erikson’s theory of psychosocial development, the contribution that it has made to the field of developmental psychology cannot be ignored. In addition to expanding the possibility of development into old age and incorporating societal and cultural influences on development, his model has been the inspiration for the work of many other developmental theorists.

George Vaillant

Similar to Erikson, George Vaillant (1977) believed that the ego evolves and develops as it passes through stages throughout the life span. Based on data collected from the Grant Foundation study of Harvard graduates begun in 1937, Vaillant revised Erikson’s eight-stage model by adding two additional stages in adulthood. First, after Stage 6, “intimacy,” Vaillant found evidence for a stage that he called “career consolidation versus self-absorption.” Individuals who face career consolidation have already established intimacy in the previous stage and are now ready to identify with a career or occupational commitment. These issues seem to preoccupy adults in early adulthood prior to experiencing generativity (Vaillant & Milofsky, 1980). The second additional stage, “keepers of the meaning versus rigidity,” was introduced after Stage 7, “generativity.” The difference between generativity and keepers of the meaning lies in the basic concepts of caring and wisdom. Generativity includes those who demonstrate the capacity for care, productivity, and guidance for the next generation; however, keepers of the meaning emote a sense of wisdom and cultural preservation. Whereas the earlier generativity stage focuses on more concrete expressions of caring and transmission to the next generation, keepers of the meaning reflects a more abstract exchange of ideology and values.

Although the focus of Vaillant’s theory is also the development of the ego, the process is quite different from that in Erikson’s model, where each stage is marked by a task that involves resolving a conflict. According to Vaillant’s theory, the ego evolves through the process of interpreting the environment and daily experiences through Freudian defense mechanisms. However, unlike Freud’s use of defense mechanisms as protectors of the ego, Vaillant utilizes defense mechanisms as central to a lifelong process through which the ego matures and develops by adapting to conflict between the environment and inner consciousness. Findings from the Grant Foundation study (Vaillant, 1977) support this conclusion by demonstrating that throughout adulthood the quality of the defense mechanism matures. In particular, Vaillant noted that immature defenses such as denial and projection were utilized less often and that mature defenses such as intellectualization, sublimation, and humor were used more often as the individual advances through the stages of adulthood. These findings were supported in a study that expanded on the Harvard sample by adding a group of inner-city adults who were interviewed at ages 25, 32, and 47 (Vaillant & Milofsky, 1980). Further, these authors concluded that although their findings demonstrate that personality unfolds in a predetermined sequential manner, ego maturation is open-ended and has no fixed chronological age. In essence, the opportunity for the personality to develop, mature, and change exists throughout adulthood.

The major contribution of Vaillant’s work with the Grant Foundation study (Vaillant, 1977; Vaillant & Milofsky, 1980) is the longitudinal nature of the study design. With data collected at multiple time points, changes in the use of defense mechanisms could be identified, and movement through the stages of ego development could be tracked. For instance, results from Vaillant’s longitudinal studies cast doubt on Levinson’s claim of a midlife crisis by revealing that individuals in midlife are no more likely than individuals at other stages of adulthood to experience significant life events that are often associated with the midlife crisis (Costa & McCrae, 1980; Lachman & Bertrand, 2001).

Despite the positive contributions that Vaillant’s work has made to the field, some limitations should be noted. For instance, the Grant Foundation study (1977) was comprised of a group of well-educated, White, middle-class males, therefore restricting the generalizability of the findings to a larger population. A follow-up study conducted by Vaillant and Milofsky (1980) added a group of inner-city men to the sample, thereby broadening the generalizability to include other socioeconomic groups, but still restricting it to males. An additional limitation of the Grant Foundation study is that the data were collected as descriptive narratives. Although they can provide a rich picture, the subjective nature of the data collection and coding methods place some limits on the interpretation of the findings. Finally, although Vaillant has set forth a model of life-span personality development, the studies in which he tested the model did not include adults beyond the age of 47. As a result, the final two stages of the model (keepers of the meaning and integrity) were not empirically tested.

Daniel Levinson

Other theories, such as Daniel Levinson’s stage theory (1977), emerged at about the same time as Vaillant’s theory and were also inspired by the writings of Erikson. Similar to Erikson’s stage theory, Levinson’s theory of adult development has a series of distinct, sequential stages that span the life-course and are each associated with a specific developmental task. In addition, as in Erikson’s theory, each stage, when accomplished, becomes the foundation for the next stage. However, rather than a model of ego development as proposed by Erikson, the central theme of Levinson’s theory is the life structure. The life structure evolves through five stages (i.e., preadulthood; early adulthood; middle adulthood; late adulthood; and late, late adulthood) by fluctuating between phases of relative stability (life structure) and phases of transition (Levinson, 1978). During the transitional phase the individual reappraises the existing life structure and explores the possibility of change by analyzing his or her internal and external world. The end product of the transitional phase is a committed choice and the beginning of a phase of stability during which a new life structure is built and expanded.

Levinson argues that the transitional phases are universal and necessary aspects of development. As the individual settles into building a life structure around choices that were made during the previous transitional phase, mistakes and regrets come to be realized. The urge to rectify and change these choices eventually becomes paramount and catapults the individual into the next transitional phase (Levinson, Darrow, Kline, Levinson, & McKee, 1978).

Although Levinson’s theory spans the entire life course, he is most noted for the midlife transitional phase. According to Levinson et al. (1978), the midlife crisis is the product of the tension and stress caused by resolving the conflict between four opposing forces. Adopted from Jung’s theory of opposing polarities, Levinson argued that middle-aged adults struggle between the competing forces of young versus old, destruction versus creation, masculine versus feminine, and attachment versus separation. The tension during the transitional phase is resolved and the next life structure begun when midlife adults have accepted that these opposing forces can coexist within themselves.

Regardless of the notoriety and popularization of the term midlife crisis, there is little support for its widespread occurrence (see Lachman & Bertrand, 2001; McCrae & Costa, 1990; Whitbourne, 1986a). Several limitations of Levinson’s data from which his theory was derived have been identified. First, the sample was small (N = 40) and consisted wholly of well-educated men, three quarters of whom were engaged in professional careers. Subsequently, Levinson conducted a similar study with women (Levinson & Levinson, 1996) and concluded that similar patterns and developmental fluctuations between life structure and transitional phases existed for women.

A second limitation of Levinson’s work comes from the fact that the research was based on qualitative clinical interview data that were not statistically analyzed. Qualitative, retrospective reports are inherently biased because of the subjectivity of the respondent and the interpreter. In fact, Levinson acknowledged that “at 46, I wanted to study the transition into middle age in order to understand what I had been through myself” (Levinson et al., 1978, p. x). A final limitation of this descriptive study is that it was a based on a cross-sectional design that captured only one point in time. To understand the nature of the transitions that Levinson describes and to make statements regarding change in behavior from one stage to the next, it is necessary to follow a cohort or group of individuals over time.

Despite its methodological limitations, Levinson’s work has made a valuable contribution to the field for underscoring the need for sound scientific research on psychological development in the middle years of adulthood and by adding to the growing body of literature that attempts to describe developmental change throughout the life course and into old age.

Jane Loevinger

Intrigued by the writing of Erikson, Jane Loevinger (1976) conceptualized a theory of ego development that was based on Erikson’s psychosocial model, although it was modified theoretically. For both Erikson and Loevinger, the ego was theorized to mature and evolve through stages across the life span as the result of a dynamic interaction between the inner self and the outer environment. However, according to Loevinger, the ego was a more complex structure than described by Erikson. For instance, she placed a strong emphasis on the importance of considering moral development when attempting to understanding personality. She argued that individual differences are central to personality and that by tracing moral stages of development, individual differences in adult personality will be revealed (Loevinger, 1983). Loevinger’s theory defines the ego as the organizer, synthesizer, and interpreter of cognition, morality, the self, and other related concepts that encapsulate personality (Loevinger, 1976, 1983). The individual’s progression through the stages is motivated by the need to interpret and adjust to changes in the outer social and inner biological environments. During this process, the personality develops slowly as the individual gains an increasingly more precise understanding of him- or herself.

Six of Loevinger’s 10 stages or transitional levels of ego development are relevant to adulthood: conformist, conscientious-conformist, conscientious, individualistic, autonomous, and integrated (Loevinger, 1983). Each stage is related to an increasingly differentiated ego that strives toward perfection. The point of ego perfection is reached in the final, integrated stage, when a discrepancy no longer exists between who the individual really is and how the individual acts. At this stage of development there is a complete acceptance of inner conflict, and outward behavior becomes the expression of the true inner self (Loevinger, 1983). Although Loevinger did not believe that all individuals develop through the final stages of her model, she argued that it is unlikely that they will revert to a prior cognitive level once a higher level has been attained (Loevinger, 1976).

To build the sequential model of ego development, Loevinger used data from the Sentence Completion Test (SCT; Loevinger,Wessler, 1970). Originally designed to measure the ego development of women, the SCT has since been revised to include men (Loevinger, 1985). The measure consists of a series of sentence fragments that respondents are required to complete. Responses are scored according to the developmental stage that they represent. Support for the SCT as a measure of ego development has been demonstrated instudiesinwhichconvergentvaliditywasestablishedagainst tests of similar concepts (e.g., Kohlberg’s test of moral maturity; Kohlberg & Kramer, 1969; see Loevinger, 1979). In a more recent study that included adults from diverse racial and socioeconomic backgrounds, the validity of the test items for use with a male population was examined (Loevinger, 1985). Results of these analyses indicate that although the items were more valid for women than for men, when differences in variability were corrected, the resulting estimates were similar, and justification for the use of the SCT with men and women was concluded.

The SCT has been used by many psychologists, particularly those whose research has focused on the interface between cognitive and ego development (e.g., Blanchard-Fields, 1986; Hy & Loevinger, 1996; Labouvie-Vief, Hakim-Larson, & Hobart, 1987). For example, in a study that examined coping strategies across the life span, Labouvie-Vief et al. (1987) found that ego level as measured by the SCTwas a strong predictor of the use of coping strategies from childhood to old age.

The advantages of Loevinger’s theory of ego development are twofold. First, similar to Erikson’s psychosocial theory of ego development, it considers as viable the possibility of development throughout the life span. In addition, the stages postulated by Loevinger are not restricted by chronological age. As a result, individual differences in the pattern of progression through the stages are possible. Second, Loevinger has constructed a measure of ego development that has made it possible to test the model empirically. This is a clear advantage over Erikson’s theory, where very little research has been conducted because of the difficulty in quantifying the stages.

Unfortunately, the generalizability of Loevinger’s work has a few limitations. One is the lack of longitudinal studies to test this life-span model. Without longitudinal research designs, individual differences in the patterns of sequencing through the stages cannot be addressed, and statements that draw such conclusions cannot be made. A second limitation of Loevinger’s work is the fact that the scoring of the ego development instrument is somewhat subjective and difficult to standardize.

In summary, the theories and research just presented that represent stage models of personality development have demonstrated support for the concept of lifelong development. Indeed, the theorists and the models of development that they have proposed that were discussed in this section have served to advance the life-span view of personality and to inspire other researchers in the field. Despite the obvious contributions that have been made by these theorists, limitations have also been identified. For example, most of the data collected to test the theories were gathered from samples that were biased toward highly educated, middle-class White males. As a result, the generalizability of the findings to other populations is limited. A second limitation common to most of the studies is the lack of longitudinal data. With the exception of the Rochester study (Whitbourne & Waterman, 1979; Whitbourne et al., 1992) and the Grant Foundation study (Vaillant, 1977; Vaillant & Milofsky, 1980), most of the work that has been conducted to test the models has utilized crosssectional data. This is especially problematic for theories that describe development or change across time. To address issues of change confidently, groups of individuals should be followed over time; otherwise, the question becomes one of differences between groups rather than change across time. In addition, although the theories presented cover lifelong development, the studies conducted to test the models did not include older adults. To capture an accurate picture of personality development in older adulthood, individuals of advanced age should be followed as they enter and progress through the final stages presented in the developmental models. The final limitation of the stage models of personality development that will be noted is their focus on internal forces, such as the ego, as the primary motivator of developmental change. Although environmental forces are noted for their interaction effect with internal forces, it is an inner driving force that is central to these theories.

In response to this final point, the following section presents a model that places greater emphasis on the impact of the environmental context on personality development. Contextual models emphasize the importance of the interaction between social and historical conditions and personality characteristics. According to this perspective, a behavior is not carried out in isolation, but is influenced by the continually fluctuating immediate context that was borne out of the past and proliferates into the future. In addition, some contextualists pay particular attention to the impact of cultural age norms and social transitions on development (e.g., Caspi, 1987; Helson & Moane, 1987; Neugarten, 1977).

Contextual Models

The contextual model of personality development is compatible with a life-span developmental perspective. For instance, contextual models view developmental trajectories over an extended period of time; they incorporate multidisciplinary perspectives; and they consider cultural and historical contexts in their models—all tenets of the life-span perspective (Baltes, 1983; Baltes et al., 1998). Personality, as defined by the framework of the contextual model, is the behavioral expression of the dynamic interaction between internal attributes and sociocultural and historical conditions, with a strong influence generated from the timing of transitions relative to socially prescribed age-graded roles, historical period, and nonnormative influences (Baltes, 1983). For researchers who support the contextual model of development, the timing of entry into age-graded roles is important because the meaning of these social transitions can be internalized quite differently depending on the individual’s personal life history, socioeconomic resources, and the prevailing historical context. The dynamic interaction among these parameters is theorized to hold lasting developmental implications for the individual and to bring about the effects of stability or change throughout the life course (Elder & Hareven, 1994).

Sociocultural Context

Some of the proponents of the contextual perspective focus their investigations on the impact of sociocultural contexts on personality development (e.g., Caspi, Elder, & Bem, 1987; Kohn & Schooler, 1978; Roberts, 1997; Roberts & Friend, 1998). Caspi and colleagues explored the social context in which childhood personality characteristics predict later life outcomes(e.g.,Caspi,1987;Caspietal.,1987;Caspi,Elder,& Bem, 1988). An underlying assumption that guides this research is the belief that personality is stable across the life span. With age, the stability of personality characteristics leads to an increasingly congruent, consistent way of responding to experiences across time and across situation (Caspi, 1987). Caspi’s work suggests a deterministic view of development, yet he maintains a belief in the dynamic interaction between personality traits and environmental contexts. For Caspi, it is this interaction that reinforces the consistency of personality over time.

To explain and test the sustainability of the dynamic interaction between the environment and personality, Caspi et al. (1987) defined two interactional styles: cumulative continuity and interactional continuity. Cumulative continuity is the result of the process through which the individual’s personality attributes systematically select him or her into specific environments that in turn reinforce and sustain those attributes.

For example, “maladaptive behaviors increasingly channel the individual into environments that perpetuate these behaviors; they are sustained by the progressive accumulation of their own consequences” (Caspi et al., 1987, p. 308). Interactional continuity refers to the reciprocal, dynamic interaction between individuals and their environment: “The person acts, the environment reacts, and the person reacts back” (Caspi et al., 1987, p. 308).

Using longitudinal data from the Berkeley Guidance Study, Caspi et al. (1987) determined the impact of early personality dispositions (i.e., explosive, undercontrolled behavior) on the shape of the life course by examining the consistency of interactional styles over a 30-year span; 186 men and women were interviewed at ages 10, 30, and 40. Initial data on childhood temper tantrums were obtained from clinical interviews with the participants and their mothers. Results from these analyses support the hypotheses proposed by Caspi and colleagues that patterns of maladaptive behavior persist over time and have lasting effects on the individual’s life trajectory. Findings support the idea that individuals seek out and set up reciprocal person-environment interactions, thus demonstrating a coherent way of approaching and responding to their social world. Children who were reported to display uncontrolled temper tantrums in childhood experienced difficulty across several life tasks such as jobs, marriage, and parenting (Caspi et al., 1987).

For instance, ill-tempered males from middle-class backgrounds demonstrated a progressive deterioration of socioeconomic status that rendered them indistinguishable from their working-class peers by midlife. In addition, they were less likely to receive a formal education and to hold a highstatus occupation than were their even-tempered middle-class peers. Ill-tempered women from middle-class backgrounds tended to married men who, into midlife, held and maintained low-status jobs. They were also over twice as likely to be divorced by midlife and more likely to be perceived by their husbands and children as less adequate and more ill-tempered than were their even-tempered peers.

In a related study, Caspi et al. (1988) examined the impact of childhood shyness on the transition to adulthood and explored the cumulative effects of this transitional phase on later life outcomes. Results indicate that men who had demonstrated shyness as children experienced delayed agegraded transitions in adulthood such as marriage, parenthood, and establishing a stable career. As a result of these off-time transitions for shy men, occupational status and stability as well as marital stability were compromised in adulthood. In contrast, women with a history of childhood shyness were more likely than other women to follow a conventional pattern of marriage, childbearing, and homemaking. It is quite interesting to note that the developmental trajectories for individuals with reported childhood shyness were moderated by gender.

In summary, the findings reported by Caspi et al. (1987, 1988) lend support to the concepts of cumulative and interactional continuity; individuals with specific personality styles seek out a context that will support and reinforce personality homeostasis. In turn, the individual reacts to the environment in such a way that further perpetuates sustaining personality dispositions. Children who exhibited explosive, uncontrolled behavior sought and received reciprocal reinforcement from the environment for the maintenance of their maladaptive personality dispositions into adulthood. Similarly, men with a childhood history of shyness delayed engagement in agegraded events such as marriage, parenthood, and career. Instead, they remained in an environment that continued to support their shy dispositions and delayed the transition into an environment in which they would be required to assert themselves and initiate social contacts. In contrast, shy women sought the refuge of conventional marriage patterns, thereby selecting a context that no doubt reinforced their reticent, reserved personality style.

This work also demonstrates that the lives of individuals with similar personality dispositions can follow different developmental trajectories given variance in social contexts. For example, middle-class individuals with an undercontrolled personality style showed a greater downward spiral in socioeconomic status than did their working-class peers. In addition, different life trajectories were revealed for men and women of similar personality dispositions. A final implication of this work is that late entry into age-graded transitions may lead to negative outcomes. As Neugarten (1977) and Helson, Mitchell, and Moane (1984) proposed, being off time on a given social clock can impede psychological adjustment including well-being. Overall, the work of Caspi et al. (1987, 1988) lends support to the idea that interactional styles, formulated early in life, are sustained throughout adulthood and serve as the underlying process through which personality characteristics remain consistent across the life span.

Additional support for the interactional continuity model comes from an investigation conducted by Roberts and Friend (1998) in which data from the Mills Longitudinal Study were prospectively examined for the impact of personality and life context patterns on career momentum (i.e., the perception of mobility in one’s career). The ongoing Mills study was begun in 1958 with a group of predominately White, middle-class female seniors from Mills College in Oakland California. Initial assessment was conducted when the women were approximately age 21 with follow-up assessments at ages 43 and 52. Data on career momentum were collected when the women were approximately age 52. Results revealed that the classification of women as exhibiting high, maintaining, or low career momentum could be determined by examining personality dispositions from 30 years earlier. Specifically, women in the high career-momentum group were more confident and independent at age 21 than were women in the maintaining or low-momentum groups. Women who were classified as maintaining career momentum scored high on measures of effective functioning and well-being at initial assessment; however, their trajectories showed a precipitous drop from age 21 to 43. Finally, women in the low-momentum group scored low on measures of self-acceptance, independence, and well-being at each assessment point across adulthood (i.e., ages 21, 43, and 52). The findings from this study also demonstrated that various life structures at age 43 were useful in predicting career momentum at age 52. For example, the high career-momentum women were engaged in higher status occupations at age 43 than were women in the other groups. Taken together, these findings suggest that status in later life on career momentum cannot be reduced to either individual differences in personality traits or variations in life contexts. Rather, they provide support for the concept of interactional continuity by highlighting the importance of the integration of personality characteristics and contextual factors in determining consistency in later life outcomes (Roberts & Friend, 1998).

Other research has also noted the importance of the dynamic interaction between personality dispositions and environmental factors. For example, to assess the relationship between occupational conditions and psychological functioning, Kohn and Schooler (1978) reinterviewed 785 men who were under the age of 65 and who had participated in a 1964 nationally representative study of civil service employees. Results from structural equation analyses demonstrated a reciprocal relationship between occupational conditions and personality characteristics. Furthermore, these analyses indicated high levels of stability on the measures of intellectual flexibility and substantive complexity over a 10-year period. Kohn and Schooler suggested that the consistency in intellectual flexibility across time reflects the stability of the social context in which people live.

Finally, Roberts (1997) found evidence for the importance of the interaction between contextual circumstances and personality dispositions in promoting change, rather than stability. Utilizing the Mills Longitudinal Study, data on women at ages 21, 27, and 43 were analyzed to explore the plaster versus the plasticity hypotheses, that is, whether personality is fixed or malleable (Roberts, 1997). Personality change patterns for each individual were examined via autoregressive latent variable models. This type of analysis allowed for the examination of interindividual differences in intra-individual change. Results revealed high rank-order consistency across adulthood on the latent personality dimensions of agency and norm adherence. However, individual differences in personality development across time were demonstrated with work experiences explaining a significant amount of variance between individuals on the personality dimensions. Increased participation and success in the work place were predictors of individual differences on the construct of agency (e.g., selfassertion, self-confidence, and independence), and increased job success was a predictor of individual differences on norm adherence. Overall, this study generated support for the plasticity of personality. Under certain contextual circumstances, change in personality is not only possible but also likely, at least into middle adulthood.

Social Clock

Neugarten (1977) and Helson (1984) were among the first to formulate contextual theories of development, basing their models on the concept of the timing of events. Development is marked by the pattern of entry into socially prescribed major life events and transitional phases. Neugarten (1977) theorized that development over the life span may occur on time or off time (early or late) with regard to cultural norms. When individuals confront events at culturally prescribed, ageappropriate times, they are considered on time, and the integrity of personality development is maintained because there is congruence between the societal expectation and the individual’s experience. On the other hand, when individuals face these events off time, they are perceived as more stressful to the individual because they are not consistent with societal expectations (Helson et al., 1984). Helson (1984) coined the term social clock to represent the phenomenon of the timing of events and argued that the degree to which the individual stays in tune with it throughout the life span determines personality consistency or change (Helson et al., 1984).

Helson et al. (1984) utilized data from the Mills Longitudinal Study to explore the usefulness of the social clock paradigm. Women were categorized into social clock groups according to the path they took to fulfill their family and work roles. The categories included (a) the Feminine Social Clock (FSC), starting a family by the early to middle 20s; (b) the Masculine Occupational Clock (MOC), choosing a career with status potential by age 28; and (c) Neither Social Clock (NSC), adhering to neither social clock by age 28. Findings revealed that personality characteristics measured in young adulthood were effective in distinguishing between social clock patterns. Women who were assessed during their early 20s with high levels of achievement, socialization, intellectual efficiency, and well-being were more likely than their lower scoring peers to adhere to the FSC. In contrast, women who in their early 20s demonstrated greater impulsivity, less awareness and internalization of conventional values, and less motivation to achieve socially structured goals were more likely than their peers to depart from the FSC pattern. Additional findings from this study support the importance of the timing of events. For example, women who by age 28 had either started families or obtained potentially high-status careers demonstrated normative, positive patterns of personality development. These on-time women scored high on scales of well-being and effective functioning in midlife. The off-time women, on the other hand, who had failed to adhere to a social clock (i.e., NSC) by their early 40s reported feeling depressed, alienated, and embittered (Helson et al., 1984).

Helson and Moane (1987) utilized the Mills Longitudinal Study to examine change in personality characteristics with reference to theories of adult development. For example, based on Gutmann’s theory (1975), it was hypothesized that femininity would decrease between the ages of 27 and 43. Considerable rank-order stability in personality dispositions was revealed; however, a normative pattern of personality change based on developmental theory was also demonstrated. As predicted, femininity increased in the younger adulthood years but decreased between the ages of 27 and 43. There was also an increase in coping skills, ego development, independence, and confidence for this group of women. This study also revealed that women who were on time in terms of beginning a family or launching a successful career changed on personality dimensions in the normative direction. However, women who were off time on these major life events failed to demonstrate normative change. The authors noted that young adults are confronted with a series of age-graded tasks that direct the developmental trajectory toward normative change if they are met at age-appropriate times.

In more recent work, Helson and colleagues (Mitchell & Helson, 1990; Helson & Wink, 1992) reexamined the Mills graduates and added an additional time of measure (i.e., age of early 50s). Hierarchical regression analyses demonstrated that a sense of well-being in early midlife significantly predicted quality of life among women in their early 50s (Mitchell & Helson, 1990). In a related study, Helson and Wink (1992) examined personality change over time and revealed evidence for inconsistency in personality dispositions in the early 40s followed by a period of stability in the early 50s. Masculinity and femininity scores were among those that resulted in the greatest magnitude of change between the ages of 43 and 52. The women in this sample demonstrated an increase in variables that are associated with masculine traits such as decisiveness and action orientation and a decrease in those associated with feminine characteristics such as vulnerability. This supports the gender-role crossover hypothesis raised by Neugarten and Gutmann (1958), which is discussed next.

In sum, the findings from the studies conducted by Helson and colleagues (Helson et al., 1984; Helson & Moane, 1987; Helson & Wink, 1992; Mitchell & Helson, 1990) illustrate that the social clock serves as a barometer by which individuals evaluate their success in the world. When on time, the individual receives social approval and a positive feeling that comes from being in sync with society. When off time, the individual may experience a lack of social acceptance that results in an unsettled feeling of detachment from society (Helson et al., 1984). The second point based on the findings from these studies is that they confirm the notion that personality dispositions are susceptible to change throughout adulthood. Although this is in contrast to the findings of Caspi et al. (1987), both lines of research emphasize the integral role that context plays in personality development across adulthood.

Gender-Role Crossover Hypothesis

The early work of Neugarten and Gutmann (1958) also supports the existence of change in personality characteristics across adulthood. Utilizing a population of adults between the ages of 40 and 70 from the Kansas City Study of Adult Lives, they explored the use of projective techniques in the study of age-sex roles. Although using a cross-sectional design, the results of this study suggest that, with age, there is a consistent shift in gender-role qualities. Respondents in the Kansas City study were presented with an ambiguous picture of an older and younger adult male and an older and younger adult female. They were then asked to create a story based on the picture. With age, respondents increasingly described the man as passive and no longer symbolizing masculine authority and the woman as assertive and controlling (Neugarten & Gutmann, 1958). These projective data, which demonstrate a cross-over of gendered attributes with older women seen as becoming more agentic and older men as more communal (J. B. James, Lewkowicz, Libhaber, & Lachman, 1995), were interpreted as additional support for the hypothesis that personality has a dynamic quality and is susceptible to over time change.

Person-Environment Fit

Earlier contextual views of personality emerged from the debate over activity (Cavan, Burgess, Havighurst, & Goldhamer, 1949) versus disengagement (Cummings & Henry, 1961) theories. Both the activity and disengagement theories are concerned with the way in which older adults adapt to decreasing roles and societal detachment. The activity theory, on one hand, proposes that detachment is imposed by society and negatively affects the well-being of the older adult unless the older adult is able to “resist the shrinkage of his social world” (Havighurst, Neugarten, & Tobin, 1996, p. 281). Older adults who remain active by finding new roles are expected to fair well. The disengagement theory, on the other hand, suggests that detachment from society is mutual with the older adult withdrawing psychologically from social activities and relationships at the same time that society withdraws support and interest from the older adult. The mutuality of withdrawal results in successful aging according to the disengagement theory.

Research findings from the Kansas City study did not support either view: that the key to well-being is to remain active or to succumb to society’s withdrawal. Rather, personality was found to play an integral role in promoting successful adaptation in later life (Havighurst et al., 1968). Achieving a match in later life with one’s life-long personal style was associated with the greatest adjustment. This finding led to the formulation of the continuity theory (Atchley, 1989), in which it was argued that either forced disengagement or forced activity leads to a loss of well-being. According to the continuity theory, older adults who are not allowed to maintain their desired level of involvement in society will suffer a loss of well-being. In some ways, this supports more recent findings about personality stability and the need to maximize person-environment fit (J. V. Lerner, Baker, & Lerner, 1985). For some, remaining active was associated with well-being, and for others becoming less involved and withdrawing was adaptive.

In sum, the contextual model provides a rich, complex format from which to view personality development. Contextual models take a life-span approach by viewing development over time in an interdisciplinary, dynamic, interactive framework. From this perspective, it is believed that personality is formed by a continuous reciprocity between the personal style that the individual brings to a situation and the social structure of the prevailing historical time period. The innovative theoretical models of Caspi, Helson, and Neugarten have advanced the field of personality psychology by adopting a life-span view and by bringing to the forefront the importance of the context in which personality evolves.

Ironically, while the advantage of the contextual framework is its multilevel, multidimensional model, it is also a disadvantage. The sophisticated methodological and statistical techniques needed to analyze change over time and to model the complex relationships among antecedents and consequences have only recently become available. Future research that tests contextual models will benefit tremendously from these advances.

Subjective Changes in Personality

As we have seen thus far, there are many methods and measures available to examine personality development across the life span. Another approach is the examination of phenomenological changes—self-perceived changes across time. Studies of subjective change show that individuals typically report more change than they show with objective indexes. In a study by Woodruff and Birren (1972), personality test scores assessed by the California Test of Personality (Kimber, 1947; Woodruff & Birren, 1971) were administered to a group of college graduates in 1944 when they were 21 years old and again in 1969 when they were approximately 46 years old. Participants were asked to complete the personality test two times during the 1969 testing occasion. Instructions given for the first test required that the respondents answer the questions based on their current personality status. Instructions for the second test required that they answer each question the way they thought they had answered in 1944 when they were 21 years old. Findings from this study revealed a high level of stability on the subjective personality ratings across the 25-year period. However, differences were found when the retrospective data were compared with the concurrent data. Results demonstrated that people remembered themselves as less well adjusted 25 years previously than their actual scores indicated. They believed that they had improved across adulthood even though there was no evidence for such a positive change. This finding suggests that adults tend to expect change, especially improvement in personality across adulthood.

Other researchers (Fleeson & Baltes, 1998; Fleeson & Heckhausen, 1997; Lachman, Walen, & Staudinger, 2000; Ryff, 1995) have also found that changes in personality are expected by a large percentage of adults. Participants were asked to rate their personalities in the past, the present, and in the future so that retrospective and prospective comparisons could be made relative to concurrent reports. In a recent study using representative samples from the United States and Germany, Fleeson and Baltes (1998) compared the predictive value of perceived changes relative to concurrent measures.A personality questionnaire (NEO; Costa & McCrae, 1984) was administered to 398 adults between the ages of 26 and 64. In addition, participants were asked to describe their own current personality, their personality when they were 20 to 25 years old, and their projected personality when they will be 65 to 70 years old. Fleeson and Baltes found that many participants anticipated change across adulthood. In addition, although they believed that late adulthood would contain more losses than gains, they expected gains at each life stage including late adulthood. It was also revealed that perceived changes in personality traits accounted for a significant amount of variance beyond the effects of concurrent ratings of personality when predicting health and well-being. This finding suggests that self-ratings of personality dimensions can add meaning when placed within the context of the life course (Fleeson & Baltes, 1998; Fleeson & Heckhausen, 1997).

Lachman et al. (2000) recently conducted a study of individual differences in past, present, and future subjective evaluations of personality characteristics in national samples from the United States and Germany. Although perceived stability of personality was the most prevalent pattern in both countries, 32% of the U.S. and 63% of the German sample showed evidence of perceived change, either incremental or decremental. Based on discriminant function analyses, results revealed that in both samples internal control beliefs were the most important variable in distinguishing between groups of individuals based on perceived change patterns. Participants with high-perceived internal control had more optimistic views of expecting stability or improvements over time, whereas those with a low sense of control remembered the past as better than the present and expected things to get worse in the future.

In general, the findings of subjective personality studies illustrate that adults hold a relatively optimistic view of their developmental trajectory. Except under certain circumstances, such as a low sense of internal control or depression, adults expect to have more positive personality attributes and greater life satisfaction in the future than in the past. The inclusion of subjective reports in the picture of personality adds another dimension to the developmental trajectory and can be useful in predicting patterns of health and well-being in later life.

Personality as a Predictor of Later Life Outcomes

Much of the research on personality development across the life span either tracks the trajectory of personality traits across time in order to assess rank-order stability or explores mean-level change to assess differences between groups. In addition to the empirical questions that can be addressed by these approaches, other interesting developmental issues can be addressed by studying the role that individual differences in personality traits play on later life outcomes (Costa & McCrae, 1988; Lachman, 1989). As discussed earlier, patterns of personality development in adulthood and old age such as health and mortality, intelligence and wisdom, and adulthood roles (e.g., marital stability/satisfaction, family, work) can be predicted by individual differences in personality attributes assessed earlier in life (e.g., Arbuckle, Gold, Andres, Schwartzman, & Chaikelson, 1992; Baltes, Smith, & Staudinger, 1992; Schwartz et al., 1995). A key issue for personality research is how the course of aging varies as a function of personality attributes.

Health

There is growing evidence that personality characteristics can influence health through a variety of psychosocial mechanisms (Smith & Gallo, 2001; Tucker & Friedman, 1996). For example, certain personality characteristics influence unstable social relationships and initiate the onset of unhealthy behaviors (e.g., smoking and excessive drinking), both potential mechanisms for the link between personality characteristics and later life morbidity and mortality. A study based on the Terman Life Cycle Study of Children with High Ability used archival data to investigate the relationships between childhood personality characteristics and longevity and health outcomes across 70 years (Tucker & Friedman, 1996). Participants in this study had been assessed on a variety of physical health and psychological factors every 5 to 10 years since 1922. A clear link between childhood personality dispositions and longevity was revealed. Specifically, social dependability and lack of impulsivity were the most significant predictors of longevity. In addition, childhood conscientiousness predicted engagement in protective health behaviors that lead to the maintenance of good health in older adulthood. Tucker and Friedman noted that given the multitude of influences on longevity, the strong link to certain personality dispositions suggests that psychological health plays a major role in physical health.

Cognitive Functioning

There is also evidence that early personality patterns are associated with cognitive functioning including intelligence and wisdom in later life. For example, data from the Seattle Longitudinal Study, an ongoing study begun in 1956 (Schaie, 1996), were analyzed to determine whether a flexible personality style was related to intellectual aging. By computing cross-lagged correlations, Schaie revealed that a flexible personality style at midlife was related to the maintenance of higher levels of intellectual performance in old age. This finding implies that a rigid response style will result in earlier declines in intellectual performance in old age. Therefore, older adults need to maintain cognitive flexibility in order to respond to the inevitable changes that are associated with advancing years (Schaie, 1996).

Additional evidence for the relationship between personality dispositions and intellectual outcomes in later life comes from a study of 326 male World War II veterans (Arbuckle et al., 1992) on whom intelligence scores had been obtained when they were young adults. It was found that being less neurotic and more intellectually active predicted reduced intellectual decline and, indirectly, better memory performance. Path models indicated that lower neuroticism scores at an earlier age were associated with higher scores on the M test (a general intelligence test used by the Canadian army) and tests of free recall in later life.

Wisdom

Wisdom has been defined as “expert knowledge in the fundamental pragmatics of life permitting exceptional insight and judgment involving complex and uncertain matters of the human condition” (Baltes et al., 1992, p. 136). In a study that explored the antecedents of wisdom, Staudinger, Lopez, and Baltes (1997) found a relationship between certain personality dimensions and wisdom. In particular, individuals who remained open to experience and interested in understanding and responding to the needs of others (i.e., psychologicalmindedness) demonstrated high levels of wisdom-related performance. Indicators of fluid and crystallized intelligence were also related to wisdom. However, after the shared variance between intelligence and personality was considered, only measures of personality-intelligence interface (e.g., judicious, creativity) contributed significant unique variance to the wisdom-related performance measure.

Midlife Crisis

Another example of personality influencing adult outcomes was found in the MIDUS Study (see Lachman & Bertrand, 2001). Those adults who were higher in neuroticism were more likely to report having a midlife crisis. The evidence suggests that it is personality style that predisposes adults to experience crises and that these crises may not be restricted to midlife but may occur at other transitional stages throughout the life course as well.

Adulthood Roles

A final domain that is relevant to the impact of personality dispositions on later life outcomes is adulthood roles such as marriage, family, and work. Kelly and Conley (1987) noted that one of the causes of marital dissatisfaction stems from intrapersonal causes of incompatibility. In other words, the personality characteristics that each partner brings to the relationship, in combination, may inhibit the well-being of the marriage. To examine this hypothesis, Kelly and Conley tested the effectiveness of personality dispositions as antecedents of marital stability and marriage satisfaction. Their longitudinal study consisted of a group of 300 couples assessed from 1930 until 1980. It was found that personality characteristics were significant predictors of both marital satisfaction and marital stability. In particular, neuroticism from the husband or the wife demonstrated the strongest relationship to the marital outcomes. Other studies that explore these phenomena were described in detail in the section in which contextual models were discussed. For example, Caspi et al. (1987, 1988) found that children who displayed explosive dispositions in childhood experienced difficulty across many life tasks such as jobs, marriage, and parenting. Further, in the domain of work and occupational status, Roberts (1997), Roberts and Friend (1998), and Kohn and Schooler (1978) demonstrated the relationship between early life personality patterns and occupational statuses.

The results of the investigations reported here provide evidence that supports the link between early life personality dispositions and later life outcomes across a broad spectrum of domains such as physical health and longevity, cognitive functioning, and the status of work and family. The implications point to the importance of establishing healthy psychological patterns of behavior early in life because they will have lasting effects that may proliferate into multiple domains of adult life.

The Self

The self is a multifaceted component at the core of personality (Markus, 1977). It is usually seen as a cognitive dimension that represents the way individuals think about and view themselves. Proponents of the self believe that personality development is an evolving process in which new information from the environment is integrated into existing knowledge structures. These knowledge structures are called schemas and are the guides and regulators of behavior (Crocker & Wolfe, 2001). Schemas are subjective interpretations of past reality that either adjust to new experience or remain the same by filtering out new information that is interpreted as threatening to the self-concept (Markus, 1977). Individuals are continually facing experiences that require the adjustment of existing schemas or the rejection of environmental information. As a result, the self-concept is in a continual state of flux between stability and change (Whitbourne, 1987). Over long periods of time, however, various aspects of the self-concept remain stable. As a result, they can be used as an anchor or resource for older adults who face later life changes.

Identity

Identity Process Theory

Identity, as defined by Whitbourne and Connolly (1999), is “the individual’s self-appraisal of a variety of attributes along the dimensions of physical and cognitive abilities, personal traits and motives, and the multiplicity of social roles including worker, family member, and community citizen” (p. 28). It is flexible and susceptible to change across the life span. Using data from a study of 94 adults ranging in age from 24 to 61, Whitbourne (1986b) developed a self-concept model based on Piagetian theory. The identity process theory (Whitbourne, 1987; Whitbourne & Connolly, 1999) moves beyond Piaget’s view, however, in that it can be used to explain the process of development across the life span. In the identity process model, identity styles are formed when the individual’s experiences are interpreted through the processes of assimilation and accommodation. Assimilation occurs by incorporating life events and new experiences into the identity. Assimilation can lead individuals to distort their views of themselves in order to preserve their self-concepts. Although it preserves a positive view of the self, in older adults an imbalance of assimilation has the potential for negative effects. Individuals with a strong assimilative style are seen as rigid and inflexible and deny age-related changes such as physical limitations. For example, they may ignore the advice of a doctor who recommends limiting physical activity. They may react to a difficult situation either by placing blame elsewhere or by avoiding situations in which their physical abilities are challenged.

In contrast to assimilation, accommodation is the process of changing the identity to conform to new experiences. An imbalance of accommodation can also bring about a negative outcome. These individuals have a weak, incoherent identity and overreact to changes. For example, the first sign of gray hair may be the catalyst that causes the adult to take on the identity of an old person. In addition, adults who rely heavily on an accommodative style fail to set goals or to make commitments. Although a balance or equilibrium between the two opposing process styles is desirable, it is the imbalance of one over the other that leads to the formation of different identity styles (Whitbourne & Connolly, 1999). When in balance, the processes produce a healthy approach to new experiences. When out of balance, however, leaning more heavily toward assimilation or accommodation, the approach is likely to be neurotic or otherwise emotionally unstable.

Whitbourne’s model of identity processing is useful for understanding the complexity and dynamic qualities of personality in adulthood and aging. It allows one to grasp the notion of an evolving identity and understand how change can occur across the life span.

Possible Selves

Another important aspect of self-concept relates to the ideas that people have about who they could become, who they would like to become, and who they are afraid of becoming. Markus and Nurius (1986) developed a theory that describes the formation of identity across the life span by addressing these aspects of the self. Their concept of possible selves incorporates hopes and dreams for the self as well as fears and anxieties of undesirable selves. These are integrated into the structure of the self and serve as motivators to achieve their hoped-for selves or to avoid their dreaded selves. When hoped-for selves are realized and feared selves are avoided, positive psychological outcomes occur. However, when the individual perceives that he or she has become the feared or dreaded self at the expense of the hoped for self, the self-concept becomes threatened, and negative outcomes result.

To describe the nature of possible selves across the life span, Cross and Markus (1991) asked a group of respondents between the ages of 18 and 86 to describe their hoped-for and feared possible selves. The groups were compared on the basis of age-related qualities. Across age groups, progressively fewer possible selves (hoped for or feared) were generated. In other words, older adults (i.e., ages 60–86) had fewer expectations of positive choices left in their lives, but they also had fewer fears. However, this should not be taken to imply that the older adults had lost hope. On the contrary, they indicated that hoped-for selves were still important to them. They were also more likely than their younger peers to focus on developing and achieving in their current roles. These personal domains suggest that self-development and growth remain important to the older adult. The fears most frequently reported by older adults were in the physical and personal domains, no doubt reflecting physical and social changes that are associated with aging.

As demonstrated by the work of Cross and Markus (1991), the concept of possible selves facilitates our understanding of the older adult’s adaptation to changing roles and losses that are commonly associated with aging. Furthermore, similar to the contextual model, the possible selves framework suggests a reciprocal model where an individual may change or adjust his or her possible selves in response to external influences and personal growth.

The Sense of Control

The sense of control can be understood as the degree to which individuals believe that their behavior will influence outcomes in their lives (Rodin, 1986). The perception that one’s behavior will affect outcomes is likely to result in a different response than if one perceives that outcomes are due to chance or other people’s actions (Bandura, 1997). Control beliefs have been found to have widespread effects in many different domains of life including work, family, and health. Furthermore, beliefs about control may vary across these different domains (Clarke-Plaskie & Lachman, 1999; Lachman & Weaver, 1998). Research findings provide evidence that control beliefs change in adulthood. For example, based on findings from the MIDUS study, Lachman andWeaver (1998) found that adults increased their sense of control over their work, finances, and marriage. However, in the domains of sex life and children, there was evidence for reduced control. In addition, other studies have found age-related declines in perceived control for health and memory (Lachman, 1991).

Control Beliefs and Health

An indirect link between control beliefs and physical health, including recovery from illness and disability in adulthood and old age, has been found (Bandura, 1997; Lachman & Prenda, in press). Individuals who believe that they are responsible for outcomes in their lives are more likely to engage in effortful and persistent behavior that is goal oriented. They believe that their health is within their own control and are confident in their ability to change. As a result, they will be more likely to act in harmony with the desired outcome by engaging in health-promoting behaviors such as exercise, a healthy diet, and regular physical examinations (Bandura, 1997; Lachman & Prenda, in press). Maintaining a sense of control in adulthood and old age may serve as an important psychosocial resource by fostering preventive and remedial health behaviors (Lachman & Bertrand, 2001). Indeed, there is compelling evidence that factors under personal control (e.g., alcohol use, smoking, mental stability, exercise, body mass index, coping mechanisms, and education) have a strong impact on psychological, physical, and social indicators of successful aging (Vaillant & Mukamal, 2001).

Self-Efficacy

The study of control beliefs has focused on many related constructs including self-efficacy, locus of control, and primary and secondary control beliefs (e.g., Bandura, 1997; Heckhausen & Shulz, 1995). Bandura (1997) argued that as adults age, they will increasingly find themselves in situations in which they will benefit by a strong sense of self-efficacy. For instance, older adults will be faced with the task of establishing new relationships to replace those that have been lost through retirement, relocation, or death.Alow sense of social efficacy in these situations will increase the older adult’s vulnerability to stress and depression by inhibiting the formation of necessary social supports (Bandura, 1997). In another situation— the routinized, controlled environment in nursing homes and other residential institutions for older adults—there is an undermining of the individual’s sense of efficacy. Numerous studies have shown that nursing home residents who have the opportunity to exert control over their environment have better physical and psychological outcomes including a longer life than those residents who do not (see Bandura, 1997).

Primary and Secondary Control

Other forms of control during adulthood and old age such as primary and secondary control beliefs have also been investigated. Heckhausen and Schulz’s (1995) model of primary and secondary control is based on the hypothesis that the individual has a strong desire to control his or her interactions with the environment. This control is accomplished by maintaining a balance between the two strategies of control. Primary control strategies involve working toward reaching a goal by changing the situation or the environment. Secondary control strategies focus on changing the self to accommodate the situation or environmental constraints.According to Heckhausen and Schulz (1995), primary and secondary control strategies work in concert to cope with the demands and challenges encountered across the life span. Evidence is provided for the notion that, with aging, there is a shift from the use of primary to secondary control strategies when faced with uncontrollable situations or difficult challenges (Heckhausen & Schulz, 1995). Additional support for age-related shifts in control strategy use comes from a study in which age-related changes in physical, cognitive, and social processes were shown to influence the developmental trajectory and resulted in the older adult’s adoption of strategies to compensate for developmental losses (Heckhausen, 1997). Finally, Wrosch, Heckhausen, and Lachman (2000) found that the use of secondary control strategies was more adaptive for older adults, whereas the use of primary control strategies was more adaptive for younger and middle-age adults when faced with health or financial difficulties.

Well-Being

Acommon myth regarding older adults is to view them as unhappy and depressed. According to Mroczek and Kolarz (1998), this misconception is the result of a belief in the social indicator model, in which social and demographic factors such as gender, income, marital status, and age serve as markers for well-being. Because older adults often experience loss in the physical and social realms, an expectation of depression and low satisfaction could erroneously be made. However, evidence is building to support the argument that regardless of the marked losses as gauged by the social indicator model, older adults are not unhappy or depressed. For example, based on the MIDUS sample, Mroczek and Kolarz (1998) found that the majority of older adults rated themselves as “very” or “pretty” happy. In general, they found that positive emotions increased and negative emotions decreased as adults reached midlife and beyond.

Ryff (1989) defined well-being along six dimensions: positive relations with others, environmental mastery, selfacceptance, having a purpose in life, personal growth, and autonomy. Ryff asked 321 adults to rate themselves along these dimensions. Results demonstrated that adults are more likely to maintain or increase well-being in terms of selfacceptance, positive relations with others, autonomy, and environmental mastery as they reach midlife and beyond. Purpose in life and personal growth was more likely to show declines in later adulthood.

Cross-national data support the findings reported here (Diener & Diener, 1996); world-wide, most adults report being happy. Across the 43 nations that were analyzed, 86% of all studies reported mean happiness and well-being ratings that were above neutral. Among older adults the percentage of participants with positive subjective well-being was between 64% and 97%. These findings suggest that adulthood and old age seem to be periods in which there is a positive sense of well-being. Because well-being can be utilized as an indicator of successful aging, the implication of these findings for older adults is that successful aging is attainable (Rowe & Kahn, 1998).

Emotions and Coping

Emotions have been defined as “the primary forces in organizing human thought and action . . . [namely,] the emotional component of consciousness and experience that gives richness and meaning to individual life and relationships” (Dougherty, Abe, & Izard, 1996, p. 17). Many argue that emotions maintain their salience and expressiveness across the life span (Dougherty et al., 1996).

Socioemotional Selectivity Theory

Carstensen (1995) suggested that, with age, emotions become more important. For example, in a study in which participants were presented with a story narrativeolder people, compared with younger people, had a better recollection of emotional text than they had for neutral text (Carstensen & TurkCharles, 1994). Carstensen noted that emotions are especially important in the social interactions of older adults, where they serve as the motivating force in the choice and maintenance of relationships. Accordingly, she conceptualized the socioemotional selectivity theory (Carstensen, 1993), an organizing conceptual framework that describes the mechanisms involved in the change in social relationships across the life span. The theory posits that there is a fundamental change in quality and quantity of the motives for maintaining social relationships with age. Although similar goals function throughout the life course, there is a change in the importance of the goals, depending on the age of the individual. For adolescents and younger adults, information seeking is the most salient factor in their selection of social relationships. They select new partners frequently because they are seeking to gain information about their social world and their place in it relative to others. In contrast, for infants and olderadults emotion regulation is the most important factor in selecting relationships. For example, older individuals are highly selective in their social relationships and generally choose partners with whom they have an established relationship. According to Carstensen (1995) emotion regulation is most salient for older adults for two primary reasons. First, with years of acquired experience, there are fewer individuals who can provide novel information to the older adult; second, as older adults become more aware of their limited time, they tend to base their relationships on the potential for emotional rewards. In this way, older adults cope with the realization that their time is limited by placing more emotional salienceon the maintenance of meaningful, long-term relationships and less on relationships that serve to provide novel information.

Coping

Lazarus (1996) noted that an understanding of coping processes is necessary to understand the concept of emotions. He argues that coping is a fundamental aspect of emotion because it incorporates the components of thinking, acting, and action impulses. Lazarus and Folkman (1984, p. 141) defined coping as “constantly changing cognitive and behavioral efforts to manage specific external and/or internal demands that are appraised as taxing or exceeding the resources of the person.” They conceptualized two approaches to coping with stress: emotion-focused and problem-focused strategies. In emotion-focused coping individuals attempt to lower their levels of stress by changing the way they view the stressor. In problem-focused coping individuals attempt to lower their levels of stress by altering or confronting the situation headon. In this type of coping strategy, the individual uses logic and planful solutions.

Several studies have been conducted that examine change in emotion- and problem-focused coping strategies across time. Of particular interest are two studies that revealed discrepant findings. The first is a study by Folkman, Lazarus, Pimley, and Novacek (1987) in which older adults were found to use less problem-focused coping and more emotionfocused (i.e., escape avoidance) styles than younger adults. However, a subsequent study by Aldwin (1991) could not replicate this finding. In fact, older adults in her study reported as many problem-focused strategies as younger adults and fewer emotion-focused strategies. Aldwin (1994) argued that adults learn to distinguish between problems that can be controlled by problem-focused strategies and those that cannot, and they may actually engage in less coping because they are aware of the best strategies that work in a given situation.

Tenacious Goal Pursuit Versus Flexible Adjustment

Related to coping strategies and similar to Heckhausen and Schulz’s (1995) primary/secondary control model and Whitbourne’s identity process theory (1987) are the concepts of tenacious goal pursuit and flexible adjustment (Brandtstädter & Renner, 1990). This model can account for how older adults cope with obstacles or difficult situations in a way that maintains their sense of well-being and prevents depression. Because adults in old age are increasingly encumbered by physical limitations and disabilities, it becomes more difficult for them to attain their desired goals. Adjustment of goals and expectancies (i.e., flexible goal pursuit) becomes adaptive in order for them to maintain a sense of well-being and avoid depression. Similar to Schaie’s (1996) work that demonstrates that a flexible personality style helps to preserve cognitive decline, flexible goal pursuits help to maintain a sense of well-being. In contrast, tenacious goal pursuits in the face of unattainable goals may lead to depression and despair.

Conclusions and Future Directions

In this research paper we have presented an overview of the field of personality development in adulthood and aging. We summarized theoretical ideas, conceptual models, and empirical research covering over five decades of work. The voluminous body of literature has enriched the field of personality development but has also made it difficult to synthesize in one paper. An attempt was made, therefore, to present key theoretical and empirical works relevant to personality development in adulthood and old age. As we have seen, researchers continue to conduct research on issues of change and stability in personality dispositions across the life span. Recently, however, the focus has shifted to include the underlying mechanisms involved in the process of personality development. The life-span perspective and the contextual models of development have supported investigations using more complex, multidimensional models. The future of research on personality in adulthood and old age must cut across disciplines to include sociocultural contexts, prevailing historical influences, physical and psychological health, genetics, and other physiological factors.

Furthermore, the trajectory of development is multidirectional and operates as a dynamic process reciprocally interacting between internal and external forces. For example, as a predictor of later life outcomes, personality transcends a particular perspective or a specific domain of later life. Given the demographic swing toward a larger percentage of older adults, a major concern for researchers, practitioners, and laypersons is the delay and prevention of age-related disease and disability. Aspects of the self such as adaptive emotional regulation, coping strategies, and control beliefs may provide an important link between early personality dispositions and later life outcomes.

Research is beginning to focus on understanding the mediators of personality and adaptive outcomes. For example, there is an emerging body of work examining the mechanisms linking aspects of personality and the self with adaptive functioning and health in adulthood and old age (Smith & Gallo, 2001). Specific personality characteristics have been linked with the onset and progression of diseases (e.g., Tucker & Friedman, 1996). Identifying behavioral and physiological factors associated with personality, such as exercise, stress hormones, and immune functioning, can provide useful information for designing interventions to promote successful aging. Such interventions are likely to be most effective if they are tailored to take individual differences in personality into account.

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