Gerben J. Westerhof and Susanne Wurm
Aging is often associated with inevitable biological decline. Yet research suggests that subjective aging—the views that people have about their own age and aging—contributes to how long and healthy lives they will have. Subjective age and self-perceptions of aging are the two most studied aspects of subjective aging. Both have somewhat different theoretical origins, but they can be measured reliably. A total of 41 studies have been conducted that examined the longitudinal health effects of subjective age and self-perceptions of aging. Across a wide range of health indicators, these studies provide evidence for the longitudinal relation of subjective aging with health and longevity. Three pathways might explain this relation: physiological, behavioral, and psychological pathways. The evidence for behavioral pathways, particularly for health behaviors, is strongest, whereas only a few studies have examined physiological pathways. Studies focusing on psychological pathways have included a variety of mechanisms, ranging from control and developmental regulation to mental health. Given the increase in the number of older people worldwide, even a small positive change in subjective aging might come with a considerable societal impact in terms of health gains.
Cornelia Wrzus and Jenny Wagner
Over the entire life span, social relationships are essential ingredients of human life. Social relationships describe regular interactions with other people over a certain period and generally include a mental representation of the relationship and the relationship partner. Social relationships cover diverse types, such as those with family members, romantic partners, friends, colleagues, as well as with other unrelated people. In general, most of these relationships change in number, contact frequency, and relationship quality during adulthood and old age. For example, both the number of and contact with friends and other unrelated people generally decrease with advancing age, whereas the number of and contact with family members remain rather stable. Relatively little is known about longitudinal changes in the quality of relationships, apart from romantic relationships, because few longitudinal studies have tracked specific relationships. Some explanatory factors, which are discussed in the literature, are (a) motivational changes, (b) reduced time due to work and family demands during adulthood, and (c) resource constraints in older age. Future work on social relationships would benefit from increasingly applying dyadic and network approaches to include the perspective of relationship partners as well as from examining online and offline contact in social relationships, which has already proved important among younger adults.
Michaela Riediger and Antje Rauers
Experience-sampling methodology (ESM) captures everyday events and experiences during, or shortly after, their natural occurrence in people’s daily lives. It is typically implemented with mobile devices that participants carry with them as they pursue their everyday routines, and that signal participants multiple times a day throughout several days or weeks to report on their momentary experiences and situation. ESM provides insights into short-term within-person variations and daily-life contexts of experiences, which are essential aspects of human functioning and development. ESM also can ameliorate some of the challenges in lifespan-developmental methodology, in particular those imposed by age-comparative designs. Compared to retrospective or global self-reports, for example, ESM can reduce potential non-equivalence of measures caused by age differences in the susceptibility to retrospective memory biases. Furthermore, ESM maximizes ecological validity compared to studies conducted in artificial laboratory contexts, which is a key concern when different age groups may differentially respond to unfamiliar situations. Despite these strengths, ESM also bears significant challenges related to potential sample selectivity and selective sample attrition, participants’ compliance and diligence, measurement reactivity, and missing responses. In age-comparative research, these challenges may be aggravated if their prevalence varies depending on participants’ age. Applications of ESM in lifespan methodology therefore require carefully addressing each of these challenges when planning, conducting, and analyzing a study, and this article provides practical guidelines for doing so. When adequately applied, experience sampling is a powerful tool in lifespan-developmental methodology, particularly when implemented in long-term longitudinal and cross-sequential designs.
Ye In (Jane) Hwang and Julian Trollor
Autism spectrum disorder (ASD), or autism, is a neurodevelopmental disorder that is typically recognized and diagnosed in childhood. There is no established biological marker for autism; rather, the diagnosis is made based on observation of behavioral traits, including (a) persistent deficits in social interaction and communication, and (b) restricted, repetitive patterns of behavior, interests, or activities. Because autism is a spectrum disorder, autistic individuals are a highly heterogeneous group and differ widely in the presentation and severity of their symptoms. The established prevalence of ASD is approximately 1% of the population.
Information about autism in adulthood is limited; most of the literature examines childhood and adolescence. While the term “later life” has traditionally been associated with those over the age of 65, a dire lack of understanding exists for those on the autism spectrum beyond early adulthood.
Individuals remain on the spectrum into later life, though some mild improvements in symptoms are observed over time. Autistic adults experience high levels of physical and mental health comorbidities. Rates of participation in employment and education are also lower than that of the general population. Quality of life is reportedly poorer for autistic adults than for nonautistic peers, though this is not affected by age. More robust studies of the health, well-being, and needs of autistic adults are needed, especially qualitative investigations of adulthood and aging and longitudinal studies of development over the lifespan.
Working memory as a temporary buffer for cognitive processing is an essential part of the cognitive system. Its capacity and select aspects of its functioning are age sensitive, more so for spatial than verbal material. Assumed causes for this decline include a decline in cognitive resources (such as speed of processing), and/or a breakdown in basic control processes (resistance to interference, task coordination, memory updating, binding, and/or top-down control as inferred from neuroimaging data). Meta-analyses suggest that a decline in cognitive resources explains much more of the age-related variance in true working memory tasks than a breakdown in basic control processes, although the latter is highly implicated in tasks of passive storage. The age-related decline in working memory capacity has downstream effects on more complex aspects of cognition (episodic memory, spatial cognition, and reasoning ability). Working memory remains plastic in old age, and training in working memory and cognitive control processes yields near transfer effects, but little evidence for strong far transfer.
John W. Rowe and Dawn C. Carr
While the factors that influence the well-being of individuals in late life have long been a major concern of research in aging, they have been a particularly active area of research and debate since the 1980s and continue to have a prominent role in gerontological research and debate. Early research on aging (from the 1920s to the 1960s) focused largely on examining typical problems that come with aging. The term successful aging was initially used to describe those who aged better than expected. In the 1980s, the MacArthur Network on Successful Aging, concerned that the field of gerontology had become preoccupied with disease and disability to the neglect of studies of the factors that fostered doing well in late life, conducted a series of studies of high-performing older persons and formulated the MacArthur theory of successful aging, which included three principal components: avoidance of disease, maintenance of physical and cognitive function, and engagement with society. Since its initial publication, the concept of successful aging has been applied to many subpopulations of older persons based on geography (East vs. West), socioeconomic status, race and ethnicity, religion, cognitive or physical function, and disease states.
Oscar Gonzalez and David P. MacKinnon
Lifespan developmental research studies how individuals change throughout their lifetime and how intraindividual or interindividual change leads to future outcomes. Lifespan researchers are interested in how developmental processes unfold and how specific developmental pathways lead to an outcome. Developmental processes have been previously studied using developmental cascade models, concepts of equifinality and multifinality, and developmental interventions. Statistical mediation analysis also provides a framework for studying developmental processes and developmental pathways by identifying intermediate variables, known as mediators, that transmit the effect between early exposures and future outcomes. The role of statistical mediation in lifespan developmental research is either to explain how the developmental process unfolds, or to identify mediators that researchers can target in interventions so that individuals change developmental pathways. The statistical mediation model is inherently causal, so the relations between the exposures, mediators, and outcomes have to be correctly specified, and ruling out alternative explanations for the relations is of upmost importance.
The statistical mediation model can be extended to deal with longitudinal data. For example, the autoregressive mediation model can represent change through time by examining lagged relations in multiwave datasets. On the other hand, the multilevel mediation model can deal with the clustering of repeated measures within individuals to study intraindividual and interindividual change. Finally, the latent growth curve mediation model can represent the variability of linear and nonlinear trajectories for individuals in the variables in the mediation model through time. As a result, developmental researchers have access to a range of models that could describe the theory of change they want to study. Researchers are encouraged to consider mechanisms of change and to formulate mediation hypotheses about lifespan development.
Agus Surachman and David M. Almeida
Stress is a broad and complex phenomenon characterized by environmental demands, internal psychological processes, and physical outcomes. The study of stress is multifaceted and commonly divided into three theoretical perspectives: social, psychological, and biological. The social stress perspective emphasizes how stressful life experiences are embedded into social structures and hierarchies. The psychological stress perspective highlights internal processes that occur during stressful situations, such as individual appraisals of the threat and harm of the stressors and of the ways of coping with such stressors. Finally, the biological stress perspective focuses on the acute and long-term physiological changes that result from stressors and their associated psychological appraisals. Stress and coping are inherently intertwined with adult development.
Scott P. Johnson
Visual scenes tend to be very complex: a multitude of overlapping surfaces varying in shape, color, texture, and depth relative to the observer. Yet most observers effortlessly perceive that the visual environment is composed of distinct objects, laid out across space, each with a particular shape that can be inferred from partial views and incomplete information. Moreover, observers generally expect objects to be continuous across space and time, to have a certain shape, and to be solid in three-dimensional (3D) space. The cortical visual system processes information for objects first by coding visual features, then by linking features into units, and last by interpretation of units as objects that may be recognizable or otherwise relevant to the observer. This way of conceptualizing object perception maps roughly onto processes of lower-, middle-, and higher-level visual processing that have long formed the basis for investigations of visual perception in adults, as well as theories of object perception, the ways visual deprivation reduces object perception skills, and the developmental time course of object perception in infancy.
Christopher Hertzog and Taylor Curley
Metamemory is defined as cognitions about memory and related processes. Related terms in the literature include metacognition, self-evaluation, memory self-efficacy, executive function, self-regulation, cognitive control, and strategic behavior. Metamemory is a multidimensional construct that includes knowledge about how memory works, beliefs about memory (including beliefs about one’s own memory such as memory self-efficacy), monitoring of memory and related processes and products, and metacognitive control, in which adaptive changes in processing approaches and strategies may be contemplated if monitoring of memory processes (encoding, retention, retrieval) indicates that alternative strategies may be required. Older adults generally believe that their memory has declined and that, on average, they have less control over memory and lower memory self-efficacy than young and middle-aged adults. Many but not all aspects of online memory monitoring are well preserved in old age, such as the ability to discriminate between information that has been learned versus not learned. A major exception concerns confidence judgments concerning whether recognition memory decisions are correct; older adults are more prone to high-confidence memory errors, believing they are recognizing something they have not encountered previously. The evidence regarding metacognitive control is more mixed, with some hints that older adults do not use monitoring to adjust control behaviors (e.g., devoting more time and effort to studying items they believe have not yet been well-learned). However, any age deficits in self-regulation based on memory monitoring or adaptive strategy use can probably be addressed through instructions, practice, or training. In general, older adults seem capable of exerting metacognitive control in memory studies, although they may not necessarily do so without explicit support or prompting.