Elizabeth Munoz

Global Perceived Stress Predicts Cognitive Change among Older Adults

Research on stress and cognitive aging has primarily focused on examining the effects of biological and psychosocial indicators of stress, with little attention provided to examining the association between perceived stress and cognitive aging. We examined the longitudinal association between global perceived stress (GPS) and cognitive change among 116 older adults (M(age) = 80, SD = 6.40, range = 67-96) in a repeated measurement burst design. Bursts of 6 daily cognitive assessments were repeated every 6 months over a 2-year period, with self-reported GPS assessed at the start of every burst. Using a double-exponential learning model, 2 parameters were estimated: (a) asymptotic level (peak performance), and (b) asymptotic change (the rate at which peak performance changed across bursts). We hypothesized that greater GPS would predict slowed performance in tasks of attention, working memory, and speed of processing and that increases in GPS across time would predict cognitive slowing. Results from latent growth curve analyses were consistent with our first hypothesis and indicated that level of GPS predicted cognitive slowing across time. Changes in GPS did not predict cognitive slowing. This study extends previous findings by demonstrating a prospective association between level of GPS and cognitive slowing across a 2-year period, highlighting the role of psychological stress as a risk factor for poor cognitive function.

Reliability and Validity of Ambulatory Cognitive Assessments

Mobile technologies are increasingly used to measure cognitive function outside of traditional clinic and laboratory settings. Although ambulatory assessments of cognitive function conducted in people’s natural environments offer potential advantages over traditional assessment approaches, the psychometrics of cognitive assessment procedures have been understudied. We evaluated the reliability and construct validity of ambulatory assessments of working memory and perceptual speed administered via smartphones as part of an ecological momentary assessment protocol in a diverse adult sample (N = 219). Results indicated excellent between-person reliability (≥0.97) for average scores, and evidence of reliable within-person variability across measurement occasions (0.41-0.53). The ambulatory tasks also exhibited construct validity, as evidence by their loadings on working memory and perceptual speed factors defined by the in-lab assessments. Our findings demonstrate that averaging across brief cognitive assessments made in uncontrolled naturalistic settings provide measurements that are comparable in reliability to assessments made in controlled laboratory environments.

A Comprehensive Comparison of Quantifications of Intraindividual Variability in Response Times: A Measurement Burst Approach

OBJECTIVES To formally identify and contrast the most commonly-employed quantifications of response time inconsistency (RTI) and elucidate their utility for understanding within-person (WP) and between-person (BP) variation in cognitive function with increasing age. METHOD Using two measurement burst studies of cognitive aging, we systematically identified and computed five RTI quantifications from select disciplines to examine: (a) correlations among RTI quantifications; (b) the distribution of BP and WP variation in RTI; and (c) the comparability of RTI quantifications for predicting attention switching. RESULTS Comparable patterns were observed across studies. There was significant variation in RTI BP as well as WP across sessions and bursts. Correlations among RTI quantifications were generally strong and positive both WP and BP, except for the coefficient of variation. Independent prediction models indicated that slower mean response time (RT) and greater RTI were associated with slower attention switching both WP and BP. For selecting simultaneous prediction models, collinearity resulted in inflated standard errors and unstable model estimates. DISCUSSION RTI reflects a novel dimension of performance that is a robust and theoretically informative predictor of BP and WP variation in cognitive function. Among the plenitude of RTI quantifications, not all are interchangeable, nor of comparable predictive utility.

Assessment of subjective cognitive impairment among older adults.

Subjective cognitive impairment (SCI) refers to an individuals everyday concerns related to cognitive functioning, which can exist even in the absence of objectively assessed impairment. SCI is common among older adults, and although symptoms may be mild, SCI is associated with subsequent cognitive decline as well as significant negative effects on everyday functional ability, mood, and social engagement. Despite the potential consequences, SCI is often underreported and undetected. Thus, it is critical to consider assessing for SCI among older adults to determine cognitive impairment risk and support early intervention to promote functional well-being and health management. The current article reviews factors related to SCI, evaluates existing methods for the assessment of SCI, and proposes a person-centered framework for enhancing assessment. Application of the framework is further illustrated through the use of clinical examples.

Daily Memory Lapses in Adults: Characterization and Influence on Affect

Objective The current analyses examined the impact of daily memory lapses on daily affect and whether this impact varied across age. Method One hundred sixty-six adults (ages 20-79) completed assessments of memory lapses and affect each day for 7 consecutive days. Assessments included retrospective and prospective memory lapses as well as the impact of these lapses (how irritating, interfering, and consequential). Affect was assessed using ratings of daily positive and negative affect. Results Participants reported memory lapses on 33.3% of days. Prospective lapses were consistently rated as more consequential. Regardless of age, participants had significantly lower in positive affect and significantly higher in negative affect on days with a prospective lapse. Effects of retrospective lapses depended on age: compared to older adults, younger adults reported lower positive affect on days with a retrospective lapse. Discussion Previous work on daily memory lapses has focused on prospective lapses. Although retrospective lapses occurred more frequently in this sample, prospective lapses appeared to have a greater impact on daily experiences regardless of age. By measuring daily memory lapses and affect over consecutive days, we can begin to understand how the experience of forgetting impacts individuals at a micro-level.

Genetic and environmental factors associated with delirium severity in older adults with dementia

To determine (1) whether delirium severity was associated with Apolipoprotein E (APOE) genotype status and occupational complexity, a measure of cognitive reserve, in individuals with delirium superimposed on dementia; and (2) whether decline in delirium severity was associated with these same factors over a post‐acute care (PAC) stay.

The Ups and Downs of Cognitive Function: Neuroticism and Negative Affect Drive Performance Inconsistency

Objectives Response time inconsistency (RTI)-or trial-to-trial variability in speeded performance-is increasingly recognized as an indicator of transient lapses of attention, cognitive health status, and central nervous system integrity, as well as a potential early indicator of normal and pathological cognitive aging (Hultsch, Strauss, Hunter, & MacDonald, 2008; MacDonald, Li, & Bäckman, 2009). Comparatively, little research has examined personality predictors of RTI across adulthood. Methods We evaluated the association between the personality trait neuroticism and RTI in a community-dwelling sample of 317 adults between the ages of 19 to 83 and tested for two indirect pathways through negative affect (NA) and cognitive interference (CI). Results The personality trait neuroticism predicted greater RTI independent of mean response time performance and demographic covariates; the results were age-invariant. Furthermore, NA (but not CI) accounted for this association and moderated mediation model results indicated that older adults were more vulnerable to the adverse effects of NA. Discussion Neuroticism predicts greater response time inconsistency irrespective of mean performance and this effect is driven largely by heightened negative emotionality that may be particularly detrimental for older adults.

The influence of social support and perceived stress on response time inconsistency

ABSTRACT Objectives: Lack of social support and high levels of stress represent potentially modifiable risk factors for cognitive aging. In this study we examined the relationships between these two risk factors and response time inconsistency (RTI), or trial-to-trial variability in choice response time tasks. RTI is an early indicator of declining cognitive health, and examining the influence of modifiable psychosocial risk factors on RTI is important for understanding and promoting cognitive health during adulthood and old age. Methods: Using data from a community sample study (n = 317; Mage = 49, range = 19–83), we examined the effects of social support, including size of network and satisfaction with support, global perceived stress, and their interactions on RTI. Results: Neither size of network nor satisfaction with support was associated with RTI independent of perceived stress. Stress was positively associated with increased RTI on all tasks, independent of social support. Perceived stress did not interact with either dimension of social support to predict RTI, and perceived stress effects were invariant across age and sex. Conclusion: Perceived stress, but not social support, may be a unique and modifiable risk factor for normal and pathological cognitive aging. Discussion focuses on the importance of perceived stress and its impact on RTI in supporting cognitive health in adulthood and old age.