Decomposing the within-person and between-person sources of variation in physical activity-cognition associations for low-active older adults

Abstract

Objectives: To examine within-person and between-person sources of variation in the relationship between physical activity and cognition in older adults participating in a walking program. To explore whether demographic, health and fitness variables, and their interactions with activity, are significant predictors of cognition.

Design: Brief longitudinal burst design.

Participants: 118 participants (91 females, mean age?=?72.81?+ 5.24 years).

Main Outcome Measures: Cognition, self-reported moderate-to-vigorous walking and self-reported moderate-to-vigorous physical activity were assessed at baseline and 6, 9, 12 and 16 weeks follow-up. Attendance at weekly walks was also recorded.

Results: Within-persons, changes in physical activity were related to select measures of executive functioning, with increased activity predictive of better cognition (three of four cognitive functions, p<.05). Between-persons, activity was also associated with cognition (two of four cognitive functions, p<.05). Younger age and higher education were related to better cognition. Interactions of demographic, health, and fitness variables with changes in within-person activity were generally non-significant.

Conclusion: The results highlight the importance of distinguishing within- from between-person effects in longitudinal analyses of the association between physical activity and cognition. This stringent within-person test of association underscores the potential value of simple physical activity interventions for improving cognitive function.     

Cognitive decline in old age: separating retest effects from the effects of growing older

Repeated administration of cognitive tests improves test performance, making it difficult for researchers to gauge the true extent of age-related cognitive decline. The authors examined this issue using data from the Rush Religious Orders Study and linear mixed-effects models. At annual intervals for up to 8 years, more than 800 older Catholic clergy members completed the same set of 19 cognitive tests from which previously established composite measures of cognitive domains were derived. Retest effects on some measures were substantial and continued to accumulate even after 8 annual test readministrations, but effects on other measures were minimal. Across cognitive measures, retest effects were not related to age, sex, or education. Individual differences in retest effects were substantial but not consistent across cognitive measures. The results suggest that retest-based improvement in cognitive test performance can be substantial and persistent.     

Separating within-person from between-person effects in the longitudinal co-occurrence of depression and different anxiety syndromes in youth

Cross-lagged panel models (CLPM) are often used to study anxiety-depression co-occurrence. However, the CLPM aggregates within- and between-person variance, which can lead to incorrect estimates. The latent curve model with structured residuals (LCM-SR) parses these sources of variance. We utilized the LCM-SR to examine prospective associations between anxiety (physical, social, separation) and depression. Youth (N = 680; M_age = 11.8; 55% female) completed measures of depression and anxiety every 3 months for 3 years (13 timepoints). The LCM-SR describing anxiety-depression co-occurrence fit well (RMSEA = 0.05, SRMR = 0.06). Depression predicted within-person change in social (b = 0.09), physical (b = 0.04), and separation anxiety (b = 0.06) over 13 timepoints. Separation anxiety predicted within-person change in depression (b = 0.08); social and physical anxiety did not. Findings advance knowledge of within-person development of anxiety-depression co-occurrence.     

Typical intellectual engagement and cognition in old age

Typical Intellectual Engagement (TIE) comprises the preference to engage in cognitively demanding activities and has been proposed as a potential explanatory variable of individual differences in cognitive abilities. Little is known, however, about the factorial structure of TIE, its relations to socio-demographic variables, and its influence on intellectual functioning in old age. In the present study, data of 364 adults (65-81 years) from the Zurich Longitudinal Study on Cognitive Aging (ZULU) were used to investigate the factorial structure of TIE and to examine the hypothesis that TIE is associated more strongly with crystallized intelligence than with fluid intelligence in old age. A measurement model of a second order factor based on a structure of four correlated first order factors (Reading, Problem Solving, Abstract Thinking, and Intellectual Curiosity) evinced an excellent fit. After controlling for age, sex, and formal education, TIE was more strongly associated with crystallized intelligence than with fluid intelligence, comparable to results in younger persons. More detailed analyses showed that this association is mostly defined via Reading and Intellectual Curiosity.     

A longitudinal multilevel model analysis of the within-person and between-person effect of effortful engagement and academic self-efficacy on academic performance

Using data from an accelerated longitudinal study, we examined the within-person and between-person effect of effortful engagement and academic self-efficacy on academic performance across students (N = 135) in elementary school. Teachers assessed participants' effortful engagement and participants rated their academic self-efficacy once per year for 3 years. Academic performance was assessed through standardized test scores in reading and math. Multilevel models indicated that within-person change in Effortful Engagement and Academic Self-Efficacy scores significantly predicted concomitant within-person change in reading test scores, B = 2.71, p = .043, Pseudo-R² = .02 and B = 4.72, p = .005, Pseudo-R² = .04, respectively. Participants with higher between-person levels of Effortful Engagement had higher initial reading test scores, B = 10.03, p = .001, Pseudo-R² = .09, and math test scores, B = 11.20, p < .001, Pseudo-R² = .15, whereas participants with higher between-person levels of Academic Self-Efficacy showed a faster rate of increase in math test scores across elementary school, B = 10.21, p = .036, Pseudo-R² = .25. At the between-person level, Effortful Engagement mediated the association between Academic Self-Efficacy and both reading and math test scores, although no support was found for mediation at the within-person level. Collectively, results suggest that trait-level psychological factors can vary meaningfully within school-aged children and that both within-person change and between-person individual differences in these traits have important consequences for academic performance.     

Word associations in old age: evidence for consistency in semantic encoding during adulthood

Word associations of 80 young and 80 older adults were compared for 113 stimulus words. The proportion of paradigmatic responses varied with the grammatical class of the stimulus word and with the vocabulary level of the subject, but not with age. The same proportion of young and older adults gave the most common responses. Although older adults had a greater number of unique responses, this seems to reflect age differences in vocabulary level, as vocabulary but not age was a good predictor. Within-subject variability was also comparable across age, as on a retest young and older adults gave the same proportion of responses that were identical to those on the original test. Both age groups were more likely to repeat common than uncommon responses on the retest. This, together with analyses of response latency, suggests equivalent use of strategic processes across age. The results indicate that semantic structure and semantic encoding in adults are related to verbal ability, but not to age.     

Exploring the within-person coupling of sleep and cognition in older African Americans

This study examined the within-person relationship between sleep and cognitive functioning. Fifty community-dwelling African Americans (age range = 50-80 years) were asked to report their sleep duration and quality the previous evening and to complete cognitive measures over 8 occasions within a 2-3 week period. A within-person daily change in sleep duration was significantly associated with worse global cognitive performance. The greater an individual deviated away from his or her average sleep duration on a particular day, the more likely his or her performance would decline. These results demonstrate that the sleep-cognition relationship can be observed at a within-person level of analysis.     

Zooming into daily life: within-person associations between physical activity and affect in young adults

Objective: Negative affect in daily life is linked to poorer mental and physical health. Activity could serve as an effective, low-cost intervention to improve affect. However, few prior studies have assessed physical activity and affect in everyday life, limiting the ecological validity of prior findings. This study investigates whether daily activity is associated with negative and positive evening affect in young adults.

Design: Young adults (N = 189, Mdn = 23.00) participated in an intensive longitudinal study over 10 consecutive days.

Main Outcome Measures: Participants wore accelerometers to objectively assess moderate-to-vigorous physical activity continuously throughout the day and reported their affect in time-stamped online evening diaries before going to sleep.

Results: On days when participants engaged in more activity than usual, they reported not only less depressed and angry evening affect but also more vigour and serenity in the evening.

Conclusion: Young adults showed both less negative and more positive affect on days with more activity. Physical activity is a promising health promotion strategy for physical and mental well-being.     

Changes in within- and between-person associations between basic psychological need satisfaction and well-being after retirement

Satisfaction of the basic psychological needs for autonomy, competence and relatedness is associated with higher well-being. However, little is known about change or stability in this association over the life span. We therefore investigated changes in the association between well-being and basic psychological need satisfaction in the retirement transition. Data was drawn from four waves of the Health, Aging, and Retirement Transitions in Sweden (HEARTS) study (N = 5,074, M (age) = 63.16; 53.61% female). Multi-level models were conducted and the analyses revealed evidence for continuity as well as systematic changes in within- and between-person associations across the retirement transition. Our findings demonstrate the benefits of applying a longitudinal design and a life span perspective on basic psychological need satisfaction.     

How perceived autonomy support and controlling coach behaviors are related to well- and ill-being in elite soccer players: A within-person changes and between-person differences analysis

ObjectivesGrounded in Basic Psychological Needs Theory (Ryan & Deci, 2002), this study examined the temporal relationships between perception of coaches' autonomy support and different facets of controlling behaviors, the satisfaction-frustration of athletes' basic needs, and subjective vitality, self-esteem and burnout in elite sportsmen.MethodsParticipants (N = 110 males) from three elite youth soccer academies in northwest France completed a questionnaire on three occasions during the last three months of the competitive season.ResultsLinear mixed models revealed that perceptions of coach-autonomy support and only two facets of controlling coach behaviors (excessive personal control and negative conditional regard) were related to basic need satisfaction-frustration, which in turn were related to the indices of well- and ill-being. In most cases, the relationships were observed both at the within- and between-person levels, but some were observed only at one level.ConclusionsThe findings highlight the importance of considering the different facets of controlling coach behaviors separately and disaggregating the between-person and within-person effects.     

Illness representations,pain and physical function in patients with rheumatic disorders: between- and within-person associations

Objectives: Rehabilitation for patients with rheumatic diseases improves both illness representations (IR) and clinical outcomes such as pain and physical functioning (PF). However, it is unclear whether IR may affect and, in turn, are affected by pain and PF. In this study, we examined both between-person associations and within-person associations between IR and pain/PF over time on three measurement occasions. Furthermore, cross-lagged relationships were examined.

Design and main outcome measures: This secondary analysis is based on data from N?=?186 patients with rheumatic diseases. Data on pain, PF and IR were assessed using self-report questionnaires at the beginning, the end and three months after a 3-week inpatient rehabilitation.

Methods: To separate between- and within-person level, data were analysed using random-intercept cross-lagged panel models.

Results: On both the between-person level (r?=?|0.21|???|0.44|) and the within-person level (r?=?|0.15|???|0.46|), pain and PF were related to cognitive and emotional IR. In addition, we found within-person bidirectional cross-lagged effects between emotional IR and PF.

Conclusion: IR show complex relationships with pain and PF. Improving PF might improve subsequent illness-related emotional distress and vice versa.     

Authenticity,presence of meaning,and struggle with ultimate meaning: Nuanced between-and within-person associations

Authenticity predicts greater presence of meaning in life, in general (between-persons) and in the moment (within-persons). However, little is known about whether authenticity predicts negative aspects of life meaning, such as struggles with ultimate meaning. Across three studies (total N = 719), two of which used daily diaries (daily reports = 1,980), correlations, confirmatory factor analyses, and multilevel path models together showed that higher levels of authenticity related positively to presence of meaning and negatively to struggle with ultimate meaning at the between- and within-person levels. These findings are consistent with humanistic, existential, and positive psychology theories of authenticity and meaning and raise the possibility that increasing authenticity states over time may predict sustained improvement in multiple aspects of meaning.     

Sex differences in cognition are stable over a 10-year period in adulthood and old age

Sex differences in declarative memory and visuospatial ability are robust in cross-sectional studies. The present longitudinal study examined whether sex differences in cognition were present over a 10-year period, and whether age modified the magnitude of sex differences. Tests assessing episodic and semantic memory, and visuospatial ability were administered to 625 nondemented adults (initially aged 35-80 years), participating in the population-based Betula study at two follow-up occasions. There was stability of sex differences across five age groups and over a 10-year period. Women performed at a higher level than men on episodic recall, face and verbal recognition, and semantic fluency, whereas men performed better than women on a task-assessing, visuospatial ability. Sex differences in cognitive functions are stable over a 10-year period and from 35 to 90 years of age.     

Age-related differences in ambulatory blood pressure during daily stress: evidence for greater blood pressure reactivity with age

Prior research on age and emotions has found that older adults may show better physiological regulation to stressful stimuli than do younger adults. However, the stress reactivity literature has shown that age is associated with higher cardiovascular reactivity to laboratory stress (J. R. Jennings et al., 1997). The authors investigated these conflicting findings further by examining daily ambulatory blood pressure in 428 middle-aged to older adults. Consistent with the age and reactivity literature, relatively old individuals showed significantly greater increases in ambulatory diastolic blood pressure compared with younger individuals when dealing with daily stressors. However, results also revealed that relatively old individuals reported less of an increase in negative affect during daily stress compared with their younger counterparts. The results of this study are consistent with the age-related increase in cardiovascular risk but highlight the complex links between stress and different facets of the aging process.     

Everyday cognition: age and intellectual ability correlates

The primary aim of this study was to examine the relationship between a new battery of everyday cognition measures, which assessed 4 cognitive abilities within 3 familiar real-world domains, and traditional psychometric tests of the same basic cognitive abilities. Several theoreticians have argued that everyday cognition measures are somewhat distinct from traditional cognitive assessment approaches, and the authors investigated this assertion correlationally in the present study. The sample consisted of 174 community-dwelling older adults from the Detroit metropolitan area, who had an average age of 73 years. Major results of the study showed that (a) each everyday cognitive test was strongly correlated with the basic cognitive abilities; (b) several basic abilities, as well as measures of domain-specific knowledge, predicted everyday cognitive performance; and (c) everyday and basic measures were similarly related to age. The results suggest that everyday cognition is not unrelated to traditional measures, nor is it less sensitive to age-related differences.     

Adult age differences in memory for name-face associations: The effects of intentional and incidental learning

Previous studies have indicated that older adults have a special deficit in the encoding and retrieval of associations. The current study assessed this deficit using ecologically valid name-face pairs. In two experiments, younger and older participants learned a series of name-face pairs under intentional and incidental learning instructions, respectively, and were then tested for their recognition of the faces, the names, and the associations between the names and faces. Under incidental encoding conditions older adults' performance was uniformly lower than younger adults in all three tests, indicating age-related impairments in episodic memory representations. An age-related deficit specific to associations was found under intentional but not under incidental learning conditions, highlighting the importance of strategic associative processes and their decline in older adults. Separate analyses of hits and false alarms indicate that older adults' associative deficit originated from high false alarm rates in the associative test. Older adults' high false alarm rates potentially reflect their reduced ability to recollect the study-phase name-face pairs in the presence of intact familiarity with individual names and faces.     

Retrieving names in old age: Short- and (very) long-term effects of repetition

Two experiments are reported that examine the effects of repetition on name retrieval in younger adults (in their 50s and 60s) and older adults (in their 70s and 80s). In Experiment 1, the subjects were asked to name a set of famous faces four times over the course of a 1-h session. Younger subjects produced significantly more correct responses than did older subjects. There was significant improvement with repeated attempts at naming, with younger and older subjects benefiting equally in terms of increasing numbers of correct responses across the session. In contrast, there was a highly significant age deficit in picture recognition over a similar retention interval. A qualitative analysis of naming responses (full name vs. part of the name) provided support for the view that aging and nonrecent use have equivalent effects on retrieval. In Experiment 2, younger subjects (but not older subjects) were significantly more likely to correctly name famous faces that they had seen 22 months previously than to correctly name new famous faces. In contrast, older subjects (but not younger subjects) were significantly more likely to produce erroneous names to famous faces that they had seen 22 months previously than to new famous faces. It is concluded that repetition priming may be relatively unaffected by aging over short retention intervals (Experiment 1) but not over a very long retention interval (Experiment 2).