The study of human development across the lifespan is inherently about patterns across time. Although many developmental questions have been tested with cross-sectional comparisons of younger and older persons, understanding of development as it occurs requires a longitudinal design, repeatedly observing the same individual across time. Development, however, unfolds across multiple time scales (i.e., moments, days, years) and encompasses both enduring changes and transient fluctuations within an individual. Measurement burst designs can detect such variations across different timescales, and disentangle patterns of variations associated with distinct dimensions of time periods. Measurement burst designs are a special type of longitudinal design in which multiple “bursts” of intensive (e.g., hourly, daily) measurements are embedded in a larger longitudinal (e.g., monthly, yearly) study. The hybrid nature of these designs allow researchers to address questions not only of cross-sectional comparisons of individual differences (e.g., do older adults typically report lower levels of negative mood than younger adults?) and longitudinal examinations of intraindividual change (e.g., as individuals get older, do they report lower levels of negative mood?) but also of intraindividual variability (e.g., is negative mood worse on days when individuals have experienced an argument compared to days when an argument did not occur?). Researchers can leverage measurement burst designs to examine how patterns of intraindividual variability unfolding over short timescales may exhibit intraindividual change across long timescales in order to understand lifespan development. The use of measurement burst designs provides an opportunity to collect more valid and reliable measurements of development across multiple time scales throughout adulthood.
Gawon Cho, Giancarlo Pasquini, and Stacey B. Scott
Eric S. Cerino and Karen Hooker
Intraindividual variability (IIV) refers to short-term fluctuations that may be more rapid, and are often conceptualized as more reversible, than developmental change that unfolds over a longer period of time, such as years. As a feature of longitudinal data collected on micro timescales (i.e., seconds, minutes, days, or weeks), IIV can describe people, contexts, or general processes characterizing human development. In contrast to approaches that pool information across individuals and assess interindividual variability in a population (i.e., between-person variability), IIV is the focus of person-centered studies addressing how and when individuals change over time (i.e., within-person variability). Developmental psychologists interested in change and how and when it occurs, have devised research methods designed to examine intraindividual change (IIC) and interindividual differences in IIC. Dispersion, variability, inconsistency, time-structured IIV, and net IIV are distinct operationalizations of IIV that, depending on the number of measures, occasions, and time of measurement, reflect unique information about IIV in lifespan developmental domains of interest. Microlongitudinal and measurement-burst designs are two methodological approaches with intensive repeated measurement that provide a means by which various operationalizations of IIV can be accurately observed over an appropriate temporal frame to garner clearer understanding of the dynamic phenomenon under investigation. When methodological approaches are theoretically informed and the temporal frame and number of assessments align with the dynamic lifespan developmental phenomenon of interest, researchers gain greater precision in their observations of within-person variability and the extent to which these meaningful short-term fluctuations influence important domains of health and well-being. With technological advancements fueling enhanced methodologies and analytic approaches, IIV research will continue to be at the vanguard of pioneering designs for elucidating developmental change at the individual level and scaling it up to generalize to populations of interest.
Jeremy B. Yorgason, Melanie S. Hill, and Mallory Millett
The study of development across the lifespan has traditionally focused on the individual. However, dyadic designs within lifespan developmental methodology allow researchers to better understand individuals in a larger context that includes various familial relationships (husbands and wives, parents and children, and caregivers and patients). Dyadic designs involve data that are not independent, and thus outcome measures from dyad members need to be modeled as correlated. Typically, non-independent outcomes are appropriately modeled using multilevel or structural equation modeling approaches. Many dyadic researchers use the actor-partner interdependence model as a basic analysis framework, while new and exciting approaches are coming forth in the literature. Dyadic designs can be extended and applied in various ways, including with intensive longitudinal data (e.g., daily diaries), grid sequence analysis, repeated measures actor/partner interdependence models, and vector field diagrams. As researchers continue to use and expand upon dyadic designs, new methods for addressing dyadic research questions will be developed.
Nasreen A. Sadeq and Victor Molinari
The need for facilities that provide residential aged care is expected to increase significantly in the near future as the global population ages at an unprecedented rate. Many older adults will need to be placed in a residential care setting, such as an assisted living facility (ALF) or nursing home, when their caregivers can no longer effectively manage serious medical or psychiatric conditions at home. Although the types of residential care settings worldwide vary considerably, long-term care residents (LTC) and staff benefit from environmental and cultural changes in LTC settings. Unlike traditional medical models of LTC, culture change advocates for a shift toward holistic, person-centered care that takes place in homelike environments and accounts for the psychosocial needs of residents. Carving out a role for family members and training professional caregivers to address behavioral problems and quality-of-life issues remain a challenge. In LTC settings, preliminary research indicates that implementing person-centered changes addressing resident and caregiver needs may lead to better health outcomes, as well as increased satisfaction among patients, families, and staff. With the burgeoning world population of older adults, it is incumbent that they be provided with optimal humane culturally sensitive care.
Roger L. Peterson and Katherine A. Lambos
A sociocultural-constructionist epistemology stands alongside more traditional psychology epistemologies for the study of aging. These positions are not commensurable. Based on Donald Peterson’s classic position on how science and practice differ in fundamental ways, on his view of “disciplined inquiry,” and Trierweiler’s view of the “local clinical scientist,” this epistemological position is more-directly relevant to practice. Within the constructionist context, it emphasizes the importance of “local” as a key level of description, along with particular levels of local knowledge. All of this is consistent with Knight’s Contextual Adult Lifespan Theory. Bruner’s ideas on cultural psychology and how culture is embedded in narrative take these ideas further. They are consistent with Bruner’s metacomments on epistemology.
Lizbeth Benson and Nilam Ram
In ecological sciences, biodiversity is the dispersion of organisms across species and is used to describe the complexity of systems where species interact with each other and the environment. Some argue that biodiversity is important to cultivate and maintain because higher levels are indicative of health and resilience of the ecosystem. Because each species performs functional roles, more diverse ecosystems have greater capability to respond, maintain function, resist damage, and recover quickly from perturbations or disruptions. In the behavioral sciences, diversity-type constructs and metrics are being defined and operationalized across a variety of functional domains (socioemotional, self, cognitive, activities and environment, stress, and biological). Emodiversity, for instance, is the dispersion of an individual’s emotion experiences across emotion types (e.g., happy, anger, sad). Although not always explicitly labeled as such, many core propositions in lifespan developmental theory—such as differentiation, dedifferentiation, and integration—imply intraindividual change in diversity and/or interindividual differences in diversity. For example, socioemotional theories of aging suggest that as individuals get older, they increasingly self-select into more positive valence and low arousal emotion inducing experiences, which might suggest that diversity in positive and low arousal emotion experiences increases with age. When conceptualizing and studying diversity, important considerations include that diversity (a) provides a holistic representation of human systems, (b) differs in direction, interpretation, and linkages to other constructs such as health (c) exists at multiple scales, (d) is context-specific, and (e) is flexible to many study designs and data types. Additionally, there are also a variety of methodological considerations in study of diversity-type constructs including nuances pertaining theory-driven or data-driven approaches to choosing a metric. The relevance of diversity to a broad range of phenomena and the utility of biodiversity metrics for quantifying dispersion across categories in multivariate and/or repeated measures data suggests further use of biodiversity conceptualizations and methods in studies of lifespan development.
Determining the mechanisms that underlie neurocognitive aging, such as compensation or dedifferentiation, and facilitating the development of effective strategies for cognitive improvement is essential due to the steadily rising aging population. One approach to study the characteristics of healthy aging comprises the assessment of functional connectivity, delineating markers of age-related neurocognitive plasticity. Functional connectivity paradigms characterize complex one-to-many (or many-to-many) structure–function relations, as higher-level cognitive processes are mediated by the interaction among a number of functionally related neural areas rather than localized to discrete brain regions. Task-related or resting-state interregional correlations of brain activity have been used as reliable indices of functional connectivity, delineating age-related alterations in a number of large-scale brain networks, which subserve attention, working memory, episodic retrieval, and task-switching. Together with behavioral and regional activation studies, connectivity studies and modeling approaches have contributed to our understanding of the mechanisms of age-related reorganization of distributed functional networks; specifically, reduced neural specificity (dedifferentiation) and associated impairment in inhibitory control and compensatory neural recruitment.
Quincy J. J. Wong, Alison L. Calear, and Helen Christensen
Internet-based cognitive behavioral therapy (ICBT) is the provision of cognitive behavioral therapy (CBT) using the Internet as a platform for delivery. The advantage of ICBT is its ability to overcome barriers to treatment associated with traditional face-to-face CBT, such as poor access, remote locations, stigmas around help-seeking, the wish to handle the problem alone, the preference for anonymity, and costs (time and financial). A large number of randomized controlled trials (RCTs) have tested the acceptability, efficacy, and cost-effectiveness of ICBT for anxiety disorders, mood disorders, and associated suicidality. A meta-review was conducted by searching PsycINFO and PubMed for previous systematic reviews and meta-analyses of ICBT programs for anxiety, depression, and suicidality in children, adolescents, and adults. The results of the meta-review indicated that ICBT is effective in the treatment and prevention of mental health problems in adults and the treatment of these problems in youth. Issues of adherence and privacy have been raised. However, the major challenge for ICBT is implementation and uptake in the “real world.” The challenge is to find the best methods to embed, deliver, and implement ICBT routinely in complex health and education environments.
Thomas M. Hess, Erica L. O'Brien, and Claire M. Growney
Blood pressure is a frequently used measure in studies of adult development and aging, serving as a biomarker for health, physiological reactivity, and task engagement. Importantly, it has helped elucidate the influence of cardiovascular health on behavioral aspects of the aging process, with research demonstrating the negative effect of chronic high blood pressure on various aspects of cognitive functioning in later life. An important implication of such research is that much of what is considered part and parcel of getting older may actually be reflective of changes in health as opposed to normative aging processes. Research has also demonstrated that situational spikes in blood pressure to emotional stressors (i.e., reactivity) also have implications for health in later life. Although research is still somewhat limited, individual differences in personal traits and living circumstances have been found to moderate the strength of reactive responses, providing promise for the identification of factors that might ameliorate the effects of age-related changes in physiology that lead to normative increases in reactivity. Finally, blood pressure has also been successfully used to assess engagement levels. In this context, recent work on aging has focused on the utility of blood pressure as a reliable indicator of both (a) the costs associated with cognitive engagement and (b) the extent to which variation in these costs might predict both between-individual and age-related normative variation in participation in cognitively demanding—but potentially beneficial—activities. This chapter elaborates on these three approaches and summarizes major research findings along with methodological and interpretational issues.
Christiane A. Hoppmann, Theresa Pauly, Victoria I. Michalowski, and Urs M. Nater
Everyday salivary cortisol is a popular biomarker that is uniquely suited to address key lifespan developmental questions. Specifically, it can be used to shed light on the time-varying situational characteristics that elicit acute stress responses as individuals navigate their everyday lives across the adult lifespan (intraindividual variability). It is also well suited to identify more stable personal characteristics that shape the way that individuals appraise and approach the stressors they encounter across different life phases (interindividual differences). And it is a useful tool to disentangle the mechanisms governing the complex interplay between situational and person-level processes involving multiple systems (gain-loss dynamics). Applications of this biomarker in areas of functioning that are core to lifespan developmental research include emotional experiences, social contextual factors, and cognition. Methodological considerations need to involve careful thought regarding sampling frames, potential confounding variables, and data screening procedures that are tailored to the research question at hand.