Cognitive Aging Research Research Articles

Introduction to the special section on cognitive plasticity in the aging mind.

Decades of cognitive aging research have led to a picture of the aging mind that is primarily characterized by gradual, though relatively broad, cognitive decline across the life span. Until recently, relatively little attention has been devoted to the question of whether there are ways to slow down, if not stop, this decline. With the special section on cognitive plasticity in the aging mind, we respond to what seems to be a beginning of the reversal of this trend (e.g., Kramer & Willis, 2002). In this short introduction, I will provide some context and a preview of the articles that appear in the special section. There have been prominent earlier attempts to assess the potential for positive change in cognitive functioning during the final decades of the life span. Perhaps, most notable in this regard is the work by P. Baltes, Kliegl, Willis, and colleagues with its emphasis on the range of plasticity rather than the assessment of current status (e.g., Baltes & Kliegl, 1992; Willis, Blieszner, & Baltes, 1982). We have learned from this work that older adults can improve their ability to solve certain reasoning or memory tasks through tailored strategy training, sometimes beyond the level of untrained young adults. However, along with this encouraging

Hindsight Bias Across the Life Span

The authors review the current state of developmental research on hindsight bias. In research on cognitive development in children as well as in cognitive–aging research, studies on hindsight bias are rare. The few existing studies indicate that children and older adults show stronger hindsight bias than young adults. The authors show commonalities and differences in hindsight bias studies in the child development and aging literatures, and suggest venues for future research toward a life span perspective on the development of hindsight bias. Special emphasis is given to the potential of theories developed for other retroactive–interference paradigms to help explain age differences in hindsight bias. Methodological challenges in investigating the development of hindsight bias are also discussed.

Pictorial Naming Specificity across Ages and Cultures: A Latent Class Analysis of Picture Norms for Younger and Older Americans and Chinese

Background: Cognitive aging research, as well as cross-cultural research, often relies on pictorial stimuli to address how perceptions of common objects vary by population group. Objective: We investigate naming specificity – the degree of detail elicited for object labels – across age (younger-older) and culture (American-Chinese). Methods: Using latent class analysis techniques, we segregated picture-item responses into multiple specificity levels. The analysis was conducted for 260 pictures, across four groups of younger (aged 17–25 years) and older (aged 59–76 years) adults in the US and mainland China. Results: Overall, three naming specificity classes were supported. Age differences were modest compared to those across culture. In particular, Chinese groups showed far greater variation, naming more items both with high and with low specificity than age-matched American counterparts. Our results differed from prior studies using familiarity and latency measures. Moreover, approximately 28% of commonly-used picture items differed across all four groups. Conclusion: These results highlight the need to select appropriate pictorial stimuli for studies involving populations diverse in age and cultural background.

Increasing Student Involvement in Cognitive Aging Research

The involvement of undergraduates in research on aging has benefits for the students and for the faculty mentors, as well as for their departments, their universities, and the field of gerontology at large. This article reports on the application of a 3-year Academic Research Enhancement Award (AREA) by the National Institute on Aging awarded to Fairfield University—a selective, midsize private Jesuit institution—to increase undergraduate involvement in cognitive aging research. The series of studies examines age-related differences in veridical and false memories arising from repeated attempts to remember information. The grant has greatly expanded the research opportunities available for undergraduates, and has provided research training to a greater number and broader range of students than was previously possible (over the 3-year period, over 30 students gained hands-on, in depth research training). Specific student research activities on the Fairfield Cognitive Aging Project are discussed, and the development of a course on supervised research, its place in the curriculum, and the immediate and long-term benefits to students are described.

Expanding the Educational Horizons of Undergraduates through Cognitive Aging Research

Involving undergraduate students in cognitive aging research requires extra efforts not associated with graduate assistants. However, if the researcher acknowledges the limited experience of undergraduates in structuring their participation, the rewards are copious for the students and researcher alike. This paper describes undergraduate student assistance in a research project supported by a National Institutes of Health Academic Research Enhancement Award grant. This is a funding mechanism tailored for 4-year teaching institutions that requires undergraduate involvement in all phases of the work. Descriptions of the researcher's institution, academic program, and student characteristics are given. Next, the recruitment and initial training of student assistants are explained. The training is tailored to provide all student assistants with a rigorous conceptual background in the research area, regardless of their ultimate responsibilities in the project. Various specializations within the project are then described, along with the student skills they require. Finally, the author reflects on this project as a growth experience of his own. Despite the special considerations needed to succeed in engaging undergraduates, the returns in the form of student growth are manifold.

Physiological Reactivity to Cognitive Stressors: Variations by Age and Socioeconomic Status

The present study focused on age and SES differences in stress reactivity in response to cognitively challenging tasks. Specifically, we assessed within-person trajectories of cortisol, a steroid hormone released by the adrenal gland in response to stressors, before, during, and after exposure to cognitively challenging tasks. We extend the current literature by simultaneously examining age and SES differences in physiological reactivity. Findings suggest that age and SES both play an important role in reactivity, such that it was the older adults with higher SES who were the most physiologically reactive to cognitive stressors. Implications of these findings for cognitive aging research are discussed.

Åldrande och kognition

Hassing, L.B. & Johansson, B. (2005). Aging and cognition. Nordisk Psykologi, 57, 1, 4–20. This article provides an overview of cognitive aging research with focus on normal aging. Results from longitudinal studies have revealed that cognitive abilities are more stable than early findings from cross-sectional studies indicated. It is also clear that crystallized abilities, such as knowledge, vocabulary, and verbal abilities are mostly stable or even may show an improvement across the adult life-span, whereas fluid abilities such as speed, executive function, working memory, and episodic memory are negatively affected in aging. Although fluid cognitive abilities tend to decline with age crystallized abilities can provide cognitive support and in this respect compensate deficits in everyday problem solving. Much research has been conducted in the last decades to identify factors that contribute to cognitive aging. It is well established that genetic, health-related (e.g., hypertension, diabetes, homocysteine, and vitamin status), as well as lifestyle factors (e.g., education, substance use, physical- and social activities) are of importance for cognitive functioning. Some of the age-related variations in cognitive performance is also mediated by changes in other cognitive processes such as speed. There is, however, still age-related variation that has not been accounted for which emphasize the need for further research and suggest that multiple aging processes affect our central nervous system and thereby various mechanisms involved in cognitive functioning.

Toward an alternative representation for disentangling age-associated differences in general and specific cognitive abilities.

Much of cognitive aging research concerns whether age-associated differences in various cognitive performances can be accounted for by general explanatory constructs or whether several specific processes are involved. Structural equation models have been proposed to disentangle general and specific age-associated differences in cognitive performance. This article demonstrates that existing methods that employ stepwise procedures run the risk of biasing results toward general resource accounts. An alternative model representation (i.e., the nested factor model) is proposed that affords simultaneous estimation of general and specific effects and is applied to data from the Berlin Aging Study. Using the nested factor model allowed the authors to detect that specific group factors explained 25% of the age-associated variance in addition to the general factor.

Short-Term versus Long-Term Longitudinal Changes in Processing Speed

Background: Previous longitudinal studies of cognitive aging have focused on long-term performance changes. A recent surge of research has demonstrated that there are reliable interindividual differences in short-term cognitive performance changes. Objective: The present study links these two pathways of cognitive aging research by examining the association between short-term (learning, practice) versus long-term (development) changes in processing speed. Methods: Data from 963 elderly participants come from the Longitudinal Aging Study Amsterdam (LASA). Results: Nested latent growth curve analyses show that the amount of learning or practice in processing speed at first measurement occasion is positively related (r = 0.72) to individual differences in development of processing speed across 6 years. Conclusions: Short-term learning or practice gains in processing speed are positively associated with long-term developmental changes in processing speed in the elderly.

Subjective cognitive complaints, memory performance, and depressive affect in old age: a change-oriented approach.

The question of whether and how subjective cognitive complaints are related to actual cognitive performance represents a central issue in applied cognitive aging research. Until recently, however, many studies have failed to find a strong association between subjective cognitive complaints and actual cognitive performance. In our study, we examine two alternative explanations: a) for methodological reasons, strong associations exist only when latent changes rather than differences are examined, and b) strong associations exist only between changes in depression and complaints, not between changes in cognitive performance and complaints. With 427 participants (M = 63 years) and two measurements, we examine both the relation between functioning, complaints, and depressive affect at each measurement point, and the relation between changes in functioning, changes in complaints, and changes in depressive affect between the measurement points with latent difference variables. The results indicate that there are substantial relations between changes in functioning, changes in depression, and changes in complaints.

Life-Span Learning: A Developmental Perspective

The article discusses learning as embedded processes of development and aging, and as social activity over the life course. The concept of life-span learning is proposed and outlined to discuss these processes as aspects of and propositions in life-span development and aging theory. Life-span learning processes arise and continuously develop in a dynamically complex body, brain, and the mind they support as essential features of development and aging over the life course. Life-span learning processes are established by evolutionary adaptive mechanisms, enriched by challenging environments, and continuously developed in supportive social structures. These ideas are derived from evolutionary biology and psychology, the cognitive sciences, life-span development and aging research, and adult development and learning studies. It is argued that life-span learning activities that challenge the body-mind-brain nexus are indispensable to optimize individual development and aging. Three global interventions and their strategies are discussed that enhance life-span learning: Learning to Learn, Learning for Growth, and Learning for Well-being.

Theoretical models of cognitive aging and implications for translational research in medicine.

We provide an overview of theoretical models of cognitive aging and present empirical research that uses these models to explain older patients' medical behaviors and to develop interventions for improving the delivery of health information and services to older adults. Theoretical accounts of age and cognition are summarized and are related to key research findings, including age differences in comprehension of medical information, adherence, and use of medical technologies. The implications of cognitive aging theories for designing optimal medical environments and enhancing adherence are discussed. Age declines in basic cognitive abilities such as working memory capacity limit older adults' ability to comprehend and recall several types of novel medical information. In contrast, automatic processes and environmental cues can benefit older adults, as shown by age increases in compliance for practiced or mentally imaged health behaviors, but can also be dangerous, as shown by older adults' greater belief in false but familiar health statements. Last, cognitive aging is shown to be a useful model for investigating cognitive disorders. Cognitive aging theories are important for understanding older patient behaviors and suggest age-related declines as well as gains in performance in medical domains. In addition, models of cognitive aging are useful in guiding the development of interventions that improve health care in older patients and in furthering our understanding of cognitive dysfunction in populations other than older adults.

The role of sensory factors in cognitive aging research.

Performance on complex, cognitive tasks often is sensitive to low-level sensory and perceptual factors. These relations are particularly important for cognitive aging researchers because aging is associated with a variety of changes in sensory and perceptual function. In the article that follows, I first selectively outline some relations between task performance and sensory function. Next, I summarize age-related changes in visual function and the implications of these changes for task performance, using the digit-symbol subtest of the WAIS as an example. I offer some reasons why age-related sensory decline may not be important to all cognitive tasks. Finally, I provide several recommendations for cognitive gerontologists who want to minimize the risk that the age differences they observe are sensory in nature.

Debates in Psychology Series: Models of Cognitive Aging: Great Things Come in Small Packages

The subject matter of this book centers on major theoretical perspectives adopted by cognitive aging researchers. Rather than focus on the various areas of cognitive change in aging, such as attention, memory, language, etc., typically broached in broad “Handbook” volumes, the editors solicited chapters devoted to research methods and theories in aging such as single-factor models, mathematical modeling, time/accuracy functions, and metaanalysis, among others. In each of the nine thoughtfully crafted chapters, the authors discuss a number of approaches to the problems of the traditional methodologies used in cognitive aging research, ranging from empirical studies to mathematical modeling.

Connecting the Many Levels and Facets of Cognitive Aging

Basic cognitive mechanisms, such as the abilities to briefly maintain, focus, and process information, decline with age. Related fields of cognitive aging research have been advancing rapidly, but mostly independently, at the biological, information processing, and behavioral levels. To facilitate integration, this article reviews research on cognitive aging at the different levels, and describes a recent integrative theory postulating that aging-related deficiencies in neurotransmission cause increased noise in information processing and less distinctive cortical representation, which in turn lead to cognitive deficits. Aging-related attenuation of catecholaminergic modulation can be modeled by lowering a neural network parameter to reduce the signal-to-noise ratio of information processing. The performance of such models is consistent with benchmark phenomena observed in humans, ranging from age differences in learning rate, asymptotic performance, and interference susceptibility to intra- and interindividual variability and ability dedifferentiation. Although the details of the conjectured sequence of effects linking neuromodulation to cognitive aging deficits await further empirical validation, cross-level theorizing of the kind illustrated here could foster the coevolution of related fields through cross-level data synthesis and hypothesis testing.

A medication screening tool for cognitive aging researchers.

A Web-based medication screening tool that provides researchers with information about side effects associated with medications commonly used by older participants is described. This tool can be used for research purposes to better separate the effects of normal, healthy aging processes from the deleterious effects often associated with medication usage. Researchers can use this tool, called SMART (Screening Medications: Aging Research Taxonomy), to (a) obtain information pertaining to the cognitive, sensory, and motor side effects associated with specific medications and (b) screen medications in their research for side effect severity. The Web address for the tool is www.psychology.gatech.edu/SMART

A medication screening tool for cognitive aging researchers.

A medication screening tool for cognitive aging researchers.

Aging and autobiographical memory: Dissociating episodic from semantic retrieval.

Cognitive aging research documents reduced access to contextually specific episodic details inolder adults, whereas access to semantic or other nonepisodic information is preserved or facilitated. The present study extended this finding to autobiographical memory by using a new measure; the Autobiographical Interview. Younger and older adults recalled events from 5 life periods. Protocols were scored according to a reliable system for categorizing episodic and nonepisodic information. Whereas younger adults were biased toward episodic details reflecting happenings, locations, perceptions, and thoughts, older adults favored semantic details not connected to a particular time and place. This pattern persisted after additional structured probing for contextual details. The Autobiographical Interview is a useful instrument for quantifying episodic and semantic contributions to personal remote memory.

Two-Year Decline in Vision but Not Hearing Is Associated with Memory Decline in Very Old Adults in a Population-Based Sample

Background: Recent cross-sectional research in cognitive aging has demonstrated a robust association between visual acuity, auditory thresholds and cognitive performance in old age. However, the nature of the association is still unclear, particularly with respect to whether sensory and cognitive function are causally related. Objective: This study aimed to determine whether marked declines in performance on screening measures of either visual acuity or auditory thresholds have an effect on cognitive decline over 2 years. Methods: The sample from the Australian Longitudinal Study of Ageing (n = 2,087) were assessed in 1992 and 1994 on measures of sensory and cognitive function as part of a larger clinical assessment. A quasi-experimental design involving comparison of extreme groups using repeated measures MANCOVA with age as a covariate was used. Results: Group performance on measures of hearing, memory, verbal ability and processing speed declined significantly. Decline in visual acuity had a significant effect on memory decline, but not on decline in verbal ability or processing speed. Decline in hearing was not associated with decline in any cognitive domain. Conclusion: The common association between visual acuity, auditory thresholds and cognitive function observed in cross-sectional studies appears to be disassociated in longitudinal studies.

The strong connection between sensory and cognitive performance in old age: Not due to sensory acuity reductions operating during cognitive assessment.

Cognitive aging research has documented a strong increase in the covariation between sensory and cognitive functioning with advancing age. In part, this finding may reflect sensory acuity reductions operating during cognitive assessment. To examine this possibility, the authors administered cognitive tasks used in prior studies (e.g., Lindenberger & Baltes, 1994) to middle-aged adults under age-simulation conditions of reduced visual acuity, auditory acuity, or both. Visual acuity was lowered through partial occlusion filters, and auditory acuity through headphone-shaped noise protectors. Acuity manipulations reduced visual acuity and auditory acuity in the speech range to values reaching or approximating old-age acuity levels, respectively, but did not lower cognitive performance relative to control conditions. Results speak against assessment-related sensory acuity accounts of the age-related increase in the connection between sensory and cognitive functioning and underscore the need to explore alternative explanations, including a focus on general aspects of brain aging.