Encyclopedia of Geropsychology

Living Edition
| Editors: Nancy A. Pachana

Personality and Aging: A Historical Review of the Research

  • Eric CerinoEmail author
  • Karen Hooker
Living reference work entry
DOI: https://doi.org/10.1007/978-981-287-080-3_100-1
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Keywords

Personality Trait Personality Disorder Personality Development Life Story Personality Structure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Synonyms

Definition

The construct of personality encompasses individual characteristics as well as the active processes of the individual’s interactions with the environment. This includes relatively enduring characteristics of one’s thoughts, feelings, and actions (i.e., traits), as well as dynamic interplays of social-cognitive processes (i.e., personal-action constructs, self-narration). Under a lifespan developmental approach, research on personality now involves both personality stability and change, growth and decline and recognizes the heterogeneity of development due to processes of adaptation across the lifespan.

Overview

Throughout the aging process, individuals encounter unique age-related challenges that have stimulated a myriad of health-related investigations from lifespan researchers in the last 50 years. Incorporating the study of personality development within the realms of gerontology has provided valuable insight on the interactions between individual characteristics and health-related behaviors expressed throughout the lifespan. Studying one’s personality can reveal, on multiple levels of analysis, the particular behaviors that are of importance to optimal aging (e.g., social support, coping strategies, exercise, and nutrition). Personality research has tremendous value in gerontology because of the capability for aspects of one’s personality to demonstrate positive growth in late adulthood (Bolkan et al. 2009). The integrative and comprehensive approaches taken today highlight the value of studying personality in aging research, and this historical review underscores the essential progress made throughout the years that have brought the field to where it is now.

The Early Years

In 1890, William James, founder of American psychology, argued that “personality is set like plaster by age 30” (James 1981, p. 126). Sigmund Freud’s work marked the beginning of theorizing about personality development by supporting James’ claim with his theory on psychosexual development. However, Freud’s theory limited the stages of development to childhood and adolescence. It was not until major theoretical frameworks from Carl Jung and Erik Erikson that the focus of personality development was broadened to be studied throughout adulthood as well. Self-preoccupation and self-discovery are two essential age-appropriate developmental tasks of Jung’s theory that extend beyond childhood. In Erikson’s theory of psychosocial development, age-related tasks and resolutions of their corresponding psychosocial crises are thought to arise throughout the lifespan in an eight-stage model. Erikson also pioneered the investigation of adults’ concern for and commitment to supporting the well-being of future generations, creating the now well-known term of generativity (Bolkan et al. 2009).

Bernice Neugarten provided empirical evidence for why personality theories explaining adult development and aging must not be based on studies of children alone. She became a pioneer in the study of personality and aging through her work with the Kansas City Studies of Adult Life, a set of studies she launched with Robert Havighurst. Results from this project denounced the idea that there is no change in adult personality. Instead, Neugarten argued for more investigation into the relationships between heterogeneity and age which paved the way for future research to focus on processes of both stability and change, and person-environment fit, throughout the lifespan (Bolkan et al. 2009).

Controversies Dividing the Field

Before the integration of stability and change was generally accepted, these distinct views separated the field into either arguing for internal processes or environmental forces directing behavior. The psychodynamic perspective can be seen in Freud’s argument for personality structure’s stability due to behavior in early childhood being governed by internal struggles from contradicting drives. Behavioral theorists opposed these claims by arguing for the plasticity of personality across the lifespan. In the 1970s, these critics stimulated the field’s divide by positing environmental factors influence personality variables, thus explaining human behavior. This debate exposed the limitations of the existing theoretical accounts, which dampened public interest in personality science (Bolkan et al. 2009).

In addition to these opposing views, personality in general is a broad and abstract construct that has historically been difficult to define. Over the decades, researchers have defined the elusive construct in various ways – applying different theoretical frameworks and utilizing various research methods. This led to dozens of different definitions and little communal agreement on what constituted an individual’s personality and how it should be measured. Difficulty in interpretation and understanding of research findings can result from this uncertainty. With this definitional inconsistency and a lessened interest in personality science threatening, little advancement occurred until the reinvigorating contributions from dispositional trait researchers. The empirical evidence from studying personality traits united the field and may arguably be one of the most substantive contributions of personality science (Bolkan et al. 2009).

The Power of the Trait Framework

The trait level of one’s personality involves a structural approach to studying the relatively enduring characteristics of one’s thoughts, feelings, and actions generally known as personality traits. These traits are the most fundamental features of an individual and are the foundation of individual differences across the lifespan. The trait framework of personality rose to prominence after multiple factor analytic studies revealed five main traits that were thought to best define personality. At the heart of this research epoch were widely accepted models known as the “five-factor” and “Big Five” models of personality (Goldberg 1993; Costa and McCrae 1992) The “Big Five” model, for example, identifies openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism (OCEAN) as the five main traits of personality (McAdams and Olson 2010). These models provided clarity and a universal language among personality researchers.

While traits are known to be generally consistent over time and context, there is considerable fluctuation in traits based on gene-environment interactions, age, and ways in which researchers measure change. Temporal stability, or the rank-order consistency of individual differences in traits, generally increases from adolescence until a peak in middle adulthood, followed by a slight decline in older adulthood. Mean-level changes, or actual increases or decreases in a trait over specific ages and time periods, show more personality change across the lifespan compared to rank-order consistency (Roberts et al. 2013). Mean-level changes in traits from adolescence to middle adulthood include increases in conscientiousness and agreeableness, and decreases in neuroticism and extraversion. This patterning of socially desirable traits, known as the “maturity principle,” is influenced by both genes and context presumably through an increase in responsibilities related to an increase in social roles in family, the work place, and community engagement (McAdams and Olson 2010).

This maturity principle peaks in middle adulthood and is followed by increases in neuroticism and decreases in agreeableness in older adulthood, though studies on very late adulthood are relatively sparse. According to the lifespan developmental perspective, the decreased capability of proficient biological plasticity results in age-related declines in the physical, cognitive, and social dimensions of health. As a result, older adults face challenges in their ability to sustain the positive characteristics displayed in middle adulthood. Increases in depression, neuroticism, and negative effects from stress suggest the possibility of a decline in the positive aspects of personality traits with aging (McAdams and Olson 2010).

While the power of the trait framework is elegant in its simplicity, it is limited in its coverage of the dynamic nature of personality and investigation of differences within the individual, known as intraindividual variability. Ways in which personality predicts various outcomes in aging populations is best understood when taking a holistic approach that involves both personality traits and processes (Hooker and McAdams 2003).

Traits Predict Many Outcomes

Personality traits are related to countless intra- and interpersonal outcomes across the lifespan and are fundamental pieces in establishing and maintaining healthy or unhealthy trajectories in life. In aging populations, particular interest is placed upon the traits that predict physical and mental health, well-being, longevity, cognitive ability, and meaningful engagement in society amid age-related declines and mortality risks. Each trait from the “Big Five” model, especially conscientiousness and neuroticism, and other dispositional characteristics have primary and moderating roles in age-related outcomes in older adults (Friedman and Kern 2014).

Being conscientious, defined as dependable, organized, dedicated, and sensible, is instrumental in creating healthy trajectories across the lifespan. Higher levels of conscientiousness have been related to lower mortality risk due to consistent healthy behaviors and decision-making. Individuals high in conscientiousness pursue environments that promote health and well-being rather than place them at greater risk. For example, conscientiousness has been related to less smoking, better diet, seat belt compliance in cars, pursuit and achievement of education goals, marriage stability, and personal friendships at home and the workplace with other conscientious individuals. In union with these healthy lifestyle patterns, conscientious individuals assess health problems with better coping strategies and other studies have found relationships with the trait and reduced disease development and less symptoms. Possessing conscientious qualities may be important for cognitive health as well, as some research has found low levels of the trait to predict cognitive impairment and diseases such as Alzheimer’s disease (Friedman and Kern 2014).

Having high levels of conscientiousness can also moderate the unhealthy trajectory high levels of neuroticism predicts across the lifespan. Neuroticism is characterized by being insecure, emotionally unstable, worrisome, and anxious, and predicts negative feelings, health complaints, higher stress, and lower levels of subjective health. Being conscientious may reduce these trait expressions amid health problems through effective emotion regulation strategies that help individuals recover from detrimental emotional stressors (Friedman and Kern 2014). There has been conflicting evidence related to neuroticism, with some studies showing neuroticism levels predicting higher mortality risk, some showing lower mortality risk, and some report no substantive prediction of mortality risk. The lowered mortality risk association with neuroticism seems to be characteristic of “healthy neuroticism,” defined as individuals who utilize worry and concern in beneficial ways (e.g., going to the doctor’s office for a checkup). This inconsistency in the literature brings a greater awareness to the importance of studying multiple personality traits together to see if other factors are contributing to symptom expression or health trajectories (Friedman and Kern 2014).

Lower levels of neuroticism and higher levels of agreeableness, extraversion, conscientiousness, and openness to experiences have been related to lower risks for various diseases and possessing a greater sense of purpose in life, which is associated with positive outcomes such as life satisfaction and self-esteem. Personality traits provide a way to better understand what contributes to healthier lifestyles in older adults, and intervention research is growing with aims to increase healthier trait expressions across the lifespan (Friedman and Kern 2014).

Personality Disorders and Aging

In addition to general health-related outcomes, aging may play an important role in symptom expression of personality disorders. The DSM-5 generally defines a personality disorder as “an enduring pattern of inner experience and behavior that deviates markedly from the expectations of the individual’s culture, is pervasive and inflexible, has an onset in adolescence or early adulthood, is stable over time, and leads to distress or impairment” (American Psychiatric Association 2013). Organized into three clusters, there are ten types of personality disorders (PDs): Cluster A (odd) includes paranoid, schizoid, and schizotypal; Cluster B (dramatic or erratic) includes antisocial, borderline, histrionic, and narcissistic; and Cluster C (anxious or fearful) includes avoidant, dependent, and obsessive-compulsive. Personality disorder not otherwise specified can be diagnosed when symptoms do not fit within a specific type. An alternative approach to classification is featured in the DSM-5 as well. Based on personality functioning and the individual’s pathological personality traits, this emerging model is an attempt to address the existing approach’s shortcomings of unclear diagnoses based on individuals showing symptoms of multiple PDs (American Psychiatric Association 2013).

The median prevalence for any type of PD ranges approximately from 10 % to 14 % of the general population (Oltmanns and Balsis 2011). This approximation is most likely an underestimate of the true number due to invalid diagnostic criteria for older adults, as criteria are based on young adults, which may result in missed diagnoses in an older population (Edelstein and Segal 2011). Convenience samples of young adults and lack of longitudinal studies or valid measures for older populations create a need for more appropriate methodology. Utilizing lifespan approaches that incorporate later life environmental demands and an openness to the variability of symptom expression in different age groups may provide a clearer understanding of PD in older adults (Oltmanns and Balsis 2011).

Due to limited longitudinal research on PDs in aging populations, age-related changes in PD symptom expression are not well understood. Cross-sectional analyses comparing prevalence of PD in younger and older adults limit developmental interpretations, but provide some valuable information. There is some support for Cluster A (paranoid, schizotypal, and schizoid PDs) and Cluster C (dependent, avoidant, obsessive-compulsive PDs) increasing in prevalence or remaining stable, with Cluster B (narcissistic, histrionic, borderline, and antisocial PDs) decreasing in prevalence into later adulthood (Oltmanns and Balsis 2011). Recognizing specific age-related stressors is key to examining why symptom expression and traits of PDs may change with aging. Factors to consider include physiological and mental decline, social dynamics (e.g., smaller networks, death of peers, caregiving responsibilities), and life events (e.g., adjustment to retirement, divorce, surgeries, and hospital stays; Oltmanns and Balsis 2011).

PDs have shown comorbidity with other mental and physical health outcomes such as anxiety, depression, substance, and eating disorders (Clark 2007). Borderline PD has been related to greater risk of obesity and diabetes, and schizoid, avoidant, and obsessive-compulsive PDs have been related to coronary heart disease (Oltmanns and Balsis 2011). Treatment programs can be successful if the treatment plan is considerate of the specific qualities of each individual’s diagnosis and involves a comprehensive approach of the structure of personality. Unfortunately, individuals with PDs very rarely seek treatment for themselves because they generally possess a lack of introspection and concern for societal aid. There is no medication that specifically treats PD, but medications are used to lower comorbid symptoms like anxiety and depression (Segal et al. 2011).

Toward a More Integrative Approach

Dispositional trait research has brought the field to a much greater understanding of personality development and health-related outcomes across the lifespan. However, trait research alone does not fully capture the dynamic nature of personality. Individuals cannot be simplified to the embodiment of their expressed traits. Researchers should aim to analyze individual characteristics as well as the active processes of the individual’s interactions with the environment. In this way, a more whole, accurate depiction of the individual’s personality can be examined. Researchers recognized the importance in this and have called for a more comprehensive framework to apply to these aims (Hooker and McAdams 2003). The study of personality in recent years has adopted a general lifespan developmental approach as a result of this need. Personality theorists now study both personality stability and change, growth and decline, and recognize the heterogeneity of development due to processes of adaptation across the lifespan (Bolkan et al. 2009).

Instead of researchers fueling old debates over “stability versus change,” the field has accepted the two can coexist in tandem, with longitudinal evidence for the concurrency of the two conceptually and empirically independent aspects of personality. This shift in understanding requires new personality models that incorporate both stability and change. Hooker and McAdams aimed to answer this need with their six foci of personality model of personality development (Hooker and McAdams 2003). Integrating both personality structures and processes in a three level framework, this model enables researchers to study stability and change in personality structures and processes simultaneously. By incorporating multiple trait and social-cognitive approaches, this model examines the entire complexity of personality. The person as a dynamic whole is able to be studied as an individual embedded within relationships and social institutions throughout time and space. In line with lifespan developmental psychology, this model is founded in Developmental Systems Theory, with assumptions including plasticity, multidirectionality, and the organizing characteristics of the individual (Bolkan et al. 2009).

The Six Foci Model of Personality Development

Incorporating literature from lifespan development and personality psychology, Hooker and McAdams identified six essential indicators, or foci, of personality and personality development (Hooker and McAdams 2003). These six foci include dispositional traits, personal action constructs (PACs), life stories rooted in trait approaches, states, self-regulatory processes, and self-narration rooted in social-cognitive approaches. Each focal point represents a crucial element of either a personality structure (i.e., traits, PACs, life stories) or process (i.e., states, self-regulatory processes, self-narration) in linked pairs (i.e., traits and states, PACs and self-regulatory processes, life stories and self-narration) that correspond with each other on distinct analytical planes (i.e., one on the structural plane and one on the processes plane).

The structure-process pairs represent the three levels of analysis this model integrates and demonstrates a personality framework that features both idiographic and nomothetic approaches. Together, the model suggests that all individuals can be placed upon a continuum of a relatively universal set of traits (Level I); that some individuals may find specific goals and developmental tasks important (Level II); and that life stories are unique among all individuals (Level III; Bolkan et al. 2009; Hooker and McAdams 2003).

Level I: Traits and States

As noted earlier, the structural construct of dispositional traits accounts for broad patterns of behavior across time and different situations. The parallel process construct of states accounts for the intraindividual processes that explain dynamic change (e.g., emotions, mood, hunger, fatigue). Since states are transient processes that involve short-term change and significant variability, researchers utilize rigorous, repeated measurement designs to capture the intraindividual variability. Together, traits and states explain the individual differences between and within individuals (Bolkan et al. 2009).

Level II: Personal Action Constructs (PACs) and Self-Regulatory Processes

Personal action constructs are specific goals, developmental tasks, and motivations that are uniquely contextualized by time, place, and social roles. These constructs can be various strategies, plans, and defenses employed by an individual aimed to attain or avoid a particular outcome. Different person-environment interactions throughout one’s lifespan can reveal substantial variability in PACs that expose dynamic interplays between cognition, emotion, and the environment. The investigation of possible selves or the individuals’ ideas of what they would like to become (hoped-for selves) and what they are afraid of becoming (feared selves) has been a rich area of study in PAC research. For example, across the lifespan, younger adults exhibit possible selves related to occupations and older adults exhibit more possible selves related to health. Through research in PACs such as possible selves, researchers have found a potential for growth in older adults who find ways to selectively optimize and compensate for normative age-related declines (Bolkan et al. 2009).

PACs are parallel with self-regulatory processes that individuals must invoke to reach their goals, such as self-efficacy and sense of control. These processes are typically investigated in particular domains such as work or family and demonstrate how people actively control their own lives. Research has shown an association between mortality rates in institutionalized older adults and sense of personal control. In addition, possessing a sense of mastery has been related to successful stress reduction strategies employed by adults amid midlife challenges. Clear age differences can be seen when studying processes associated with resilience, such as self-evaluation, emotion regulation, and goal setting. This is due to individuals typically improving in maintenance of subjective well-being and adjustment to life tasks as they age, as well as the use of compensatory strategies and adaptive behaviors amid age-related loss (Bolkan et al. 2009).

The maintenance of self-regulatory processes across the lifespan can be explained through the SOC model of lifespan developmental psychology. In short, the three processes of selection, optimization, and compensation make up the universal principles of developmental regulation. An individual selects goals or outcomes, optimizes the means to achieve the goals or outcomes, and compensates for loss so that the goals or outcomes remain attainable. An example of the SOC model in older adults’ goal processes toward social relationships was presented by Baltes and Carstensen (1999). Older adults tended to select goals related to preserving family relationships. They optimized these goals by devoting more time in family relationships compared to other relationships. Finally, they compensated for the loss of friendships by maximizing their most important family relationships (Baltes and Carstensen 1999).

Adults encounter potential resource gains (e.g., practical knowledge, material possessions) and potential resource losses (i.e., physical decline) with increased age. Therefore, incorporating PACs and self-regulatory processes are critical when studying personality in aging populations because researchers must be aware of the selection and pursuit of goals that maximize gains and minimize losses. Including an individual’s personal goals and desires and the ways in which they are attained are vital to the study of personality development and optimal aging.

Level III: Life Stories and Self-Narration Processes

Life stories can be defined as the constantly evolving narrative understanding of one’s self. A life story is made through remembering the past and anticipating the future with a sense of meaning, unity, and purpose. Middle-aged and older adults have life stories with themes of “giving birth to” a new generation and overall qualities of generativity. These life stories featuring generativity aid in creating the individual’s identity. Being able to preserve a positive view of oneself amid age-related changes is critical for optimal aging (Bolkan et al. 2009).

The parallel process of self-narration can be defined as the social cognitive processes employed while constructing a life story, such as remembering, reminiscing, and storytelling. Age differences can be seen in autobiographical memories or subjective depictions of an individual’s past. For example, older adults tend to retain self-relevant and emotionally intense memories compared to younger adults. In this third level of analysis, the structural life story and the parallel self-narration processes shed light on the individual’s uniqueness and ways in which personality identity is constructed across the lifespan.

Summary of the Six Foci Model of Personality Development

This model has provided the field of personality development a comprehensive and dynamic framework that can examine stability and change concurrently across multiple foci of personality. The integrative nature of the levels in the model speak to its value in the fields of personality development and aging. For example, traits and states can manifest in infancy (but can change throughout adulthood), while PACs and life stories manifest in later childhood and adolescence and continue to develop throughout the lifespan (Hooker and McAdams 2003).

Staudinger and her colleagues have written about positive personality functioning following two trajectories: growth and adjustment (Staudinger and Kessler 2009). A structure and process approach is also presented in this framework, and the authors draw on the lifespan developmental literature to identify indicators of adjustment and indicators of growth or maturity along structure and process dimensions.

Structures and Processes in Today’s Research

The integration of the structures and processes of personality in the Six Foci model is a foundational stepping stone toward today’s research studying the underlying mechanisms that drive dispositional traits. The trait framework has been instrumental in identifying the traits that predict important outcomes across the lifespan, but it does not extend into the explanatory processes that are responsible for these trait-outcome associations. Under a lifespan developmental perspective, today’s research features integrative analyses and elaborate methodology aimed to better understand personality in its entirety. This involves investigating not only if personality traits predict certain outcomes but identifying the processes responsible for personality’s contribution to individual and interpersonal outcomes in specific contexts across the lifespan (Hampson 2012).

Personality processes are typically identified as either a moderating factor indirectly influencing an outcome known as reactive personality processes or a mediating factor directly influencing an outcome known as instrumental or self-regulative processes. In both types of processes, these mechanisms influence the trait-outcome associations and provide clearer explanation for why certain relationships exist (Hampson 2012). Both moderating and mediating processes have been identified for specific traits including neuroticism, anger, extraversion, happiness, and conscientiousness.

Typically, individuals with higher trait levels of neuroticism and anger are more emotionally reactive. It is the negative emotional responses to situations that moderate the relationship between having higher levels of neuroticism and more adverse consequential outcomes. Extraversion moderates social activity’s relationship with happiness such that individuals taking part in social activity will report greater happiness if they are more extraverted than individuals who are less extraverted. Conscientiousness has been found to moderate many predictors and health outcomes by either decreasing or increasing the magnitude of relationships. Specifically, individuals who exhibit conscientiousness are typically making direct efforts to inhibit responses and produce healthier behaviors (Hampson 2012).

Mediating processes have substantive value in intervention research, as these processes require direct effort. Health behaviors and niche selection are two mediational pathways found in neuroticism’s relationship with different outcomes. Happiness’ relationship to extraversion is mediated by social participation, although other mediating processes for happiness and extraversion remain to be understood. Further, various health behaviors mediate the relationship between conscientiousness and health outcomes (Hampson 2012).

Each of these processes aids in understanding what characteristics are most beneficial under what context. Researchers can utilize personality processes to put behaviors in context and follow developmental patterns depending on the situation. This is made possible through better longitudinal methodology, including efficient daily diary and measurement burst study designs that can follow various processes in each context experienced. Further, technological advancements have made it possible to unite personality dispositions and processes with brain mapping equipment to follow corresponding brain region activation. Uniting structural traits and various personality processes in today’s research provides the field a more comprehensive understanding of the ways in which personality impacts the aging process throughout the entire lifespan (Hampson 2012).

Conclusion

The historical underpinnings of personality and aging, the transitional migration into more integrative approaches, and the current investigations into the comprehensive whole of an individual’s personality across the lifespan have been reviewed. Studying personality under a lifespan developmental approach and integrative framework allows researchers to uncover optimal aging strategies and the potential for growth in older adults amid age-related declines. By acknowledging the concurrency of personality stability and change and the dynamic nature of personality, researchers can continue to extend the field’s understanding into the many roles personality plays across the lifespan.

Cross-References

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© Springer Science+Business Media Singapore 2016

Authors and Affiliations

  1. 1.School of Social and Behavioral Health SciencesCollege of Public Health and Human Sciences, Oregon State UniversityCorvallisUSA