Biomedical subjects

John R Nesselroade

Publications and source records attributed to John R Nesselroade.

8 recordsLinked to original sources

PubMed2006

Short-term variability in cognitive performance and the calibration of longitudinal change.

Recent studies have documented that normal adults exhibit considerable variability in cognitive performance from one occasion to another. We investigated this phenomenon in a study in which 143 adults ranging from 18 to 97 years of age performed different versions of 13 cognitive tests in three separate sessions. Substantial within-person variability was apparent across 13 different cognitive variables, and there were also large individual differences in the magnitude of within-person variability. Because people differ in the amount of short-term variability, we propose that this variability might provide a meaningful basis for calibrating change in longitudinal research. Correlations among the measures of within-person variability were very low, even after we adjusted for reliability, and there was little evidence that increased age was associated with a larger amount of within-person variability.

Adolescent↗

PubMed2005

Cognitive performance inconsistency: intraindividual change and variability.

Although many studies have examined inconsistency of cognitive performance, few have examined how inconsistency changes over time. 91 older adults (age 52 to 79) were tested weekly for 36 consecutive weeks on a series of multitrial memory speed (i.e., letter recognition) tasks. A number of multivariate techniques were used to examine how individuals' level of inconsistency changed across weeks and how this change was related to interindividual differences in age and intelligence. Results indicated that (a) inconsistency of performance is a construct separate from the underlying performance ability (i.e., memory speed); (b) inconsistency reduces exponentially with practice; (c) individuals with higher scores on tests of fluid general intelligence (G-sub(f)) reached lower asymptotic levels of inconsistency compared to lower scorers; and (d) after controlling for the systematic effects of practice, variability in inconsistency from week-to-week was more pronounced for individuals with lower G-sub(f) scores compared to individuals with higher scores.

Aged↗

PubMed2004

Methodological and theoretical implications of intraindividual variability in perceptual-motor performance.

As an individual differences variable, lability (within-person variability) has often been neglected even though it has been shown to predict key outcomes such as mortality. We examine intraindividual variability in perceptual-motor performance and relate it to chronological age in a sample of adults. The magnitude of between-session variability was found to average between 25% and 50% of the between-person variability and was equivalent in magnitude to the variation that was apparent across an age range of 12 to 27 years in cross-sectional comparisons. Age is related to the magnitude of intraindividual variability, which in turn is negatively related to performance on other cognitive tasks. Various implications of the findings are discussed.

Adult↗

PubMed2004

General slowing or decreased inhibition? Mathematical models of age differences in cognitive functioning.

Researchers have attempted to explain age-related decrements in cognitive performance in terms of reduced processing speed or decreased ability to inhibit irrelevant thoughts. We present these ideas in the context of a dynamic model derived from extensions of the classical predator-prey equation. Reduced processing speed among older adults is represented by use of delays in the dynamic model, whereas the interference imposed by distractors is captured by use of the predator-prey interaction term. We demonstrate the versatility of this modeling approach, and its pertinence to age-related behavioral change, by means of numerical simulations. In showing the applicability of these models, we identify several unresolved methodological and measurement issues that have to be addressed.

Aged↗

PubMed2003

Assessing psychological change in adulthood: an overview of methodological issues.

This article reviews the current status of methods available for the analysis of psychological change in adulthood and aging. Enormous progress has been made in designing statistical models that can capture key aspects of intraindividual change, as reflected in techniques such as latent growth curve models and multilevel (random-effects) models. However, the rapid evolution of statistical innovations may have obscured the critical importance of addressing rival explanations for statistical outcomes, such as cohort differences or practice effects that could influence estimates of age-related change. Choice of modeling technique and implementation of a specific modeling approach should be grounded in and reflect both the theoretical nature of the developmental phenomenon and the features of the sampling design that selected persons, variables, and contexts for empirical observation.

Adult↗

PubMed2003

Modeling affective processes in dyadic relations via dynamic factor analysis.

An intraindividual variability design, including application of dynamic factor models, was used to examine the affective processes of a husband-wife dyad over 182 consecutive days. Structural equation analyses indicated differences in the affective structure between the husband and the wife, and these differences were characterized in terms of their factorial configuration and temporal organization. Examination of the dyad's affective dynamics revealed unidirectional (i.e., from the husband to the wife) interpersonal influences with a defined structure over time.

Adult↗

PubMedDate not supplied

An examination of the Hofer and Sliwinski evaluation.

Although we fully endorse the thesis of Hofer and Sliwinski that all research designs and analytical procedures should be critically examined before accepting conclusions based upon them, in this commentary we question whether their critical examination is complete. In particular, we suggest that they neglected some disadvantages of longitudinal and narrow age range cross-sectional designs and that they may have been overly pessimistic with respect to the potential usefulness of cross-sectional designs for certain research questions.

Aged↗

PubMedDate not supplied

Intraindividual variability and short-term change. Commentary.

BACKGROUND: Interest in the study of intraindividual variability is growing rapidly. OBJECTIVE: The present collection of papers deals with both longer-term, growth and change and shorter-term intraindividual variability. METHODS: The papers emphasize primarily the former within the context of analyzing large, longitudinal data sets. Also discussed are some key methodological matters. RESULTS: Criteria to help with choosing methods and modeling with missing data are included. CONCLUSIONS: A promising direction is toward developing a more systematic and intensive conception of the meaning and significance of the wide variety of manifestations of intraindividual variability and integrating them into theories of aging.

Aging↗