Structural equation models of relationships between exercise and cognitive abilities

Data were obtained from 300 men and women aged 55 to 91. Separate structural equation models of relationships between physical exercise and 3 cognitive performance variables--reaction time, working memory, and reasoning--fit the data well. Other variables in the models were age, health, education, and morale. Age and exercise affected each performance variable directly; education had a direct effect on reasoning only. There were also indirect effects of age and health on performance variables, mediated through exercise. The main hypothesis of the study, that exercise contributes to performance, was supported. A large decrease in model fit resulted when the path from exercise to each performance variable was deleted. Hypotheses that age-related deficits are primarily accounted for by lack of exercise or by poor health were not supported.     

Age differences in proactive interference, working memory, and abstract reasoning

It has been hypothesized that older adults are especially susceptible to proactive interference (PI) and that this may contribute to age differences in working memory performance. In young adults, individual differences in PI affect both working memory and reasoning ability, but the relations between PI, working memory, and reasoning in older adults have not been examined. In the current study, young, old, and very old adults performed a modified operation span task that induced several cycles of PI buildup and release as well as two tests of abstract reasoning ability. Age differences in working memory scores increased as PI built up, consistent with the hypothesis that older adults are more susceptible to PI, but both young and older adults showed complete release from PI. Young adults' reasoning ability was best predicted by working memory performance under high PI conditions, replicating M. Bunting (2006). In contrast, older adults' reasoning ability was best predicted by their working memory performance under low PI conditions, thereby raising questions regarding the general role of susceptibility to PI in differences in higher cognitive function among older adults. (PsycINFO Database Record (c) 2008 APA, all rights reserved).     

Outcome Expectancies and Expectancy Accessibility in Exercise Behavior

Most people do not engage in recommended levels of physical activity. Social cognition research indicates that self‐reported outcome expectancies (OEs) are associated with exercise behavior, but self‐report assessments have limitations. We investigated whether reaction times (RTs) to endorse outcome expectancies would capture unique information about spontaneous cognitive processes associated with exercise behavior. Exercisers and sedentary participants were randomly assigned to complete an exercise test or to rest. Participants completed an OE questionnaire and RT task before and after the test/rest. On the RT task, exercisers endorsed exercise positive outcomes more rapidly than sedentary participants. Furthermore, reported OEs and RTs were independently associated with exercise status. RTs may afford a more comprehensive assessment of the cognitive processes associated with exercise behavior.     

Does Sex Matter? The Moderating Role of Sex on the Relationship Between Stress Biomarkers and Cognition

We examined the moderating role of sex on the relationship between salivary cortisol and alpha-amylase (sAA) and a diverse battery of cognitive outcomes including measures of working memory capacity, executive functioning, and prospective memory in addition to a more traditional memory measure (episodic memory). The final sample for the analyses included 144 participants (34 men and 110 women). Multiple regressions were performed to test the moderating role of sex on the stress biomarker-cognition relationship. For backward counting performance, higher cortisol levels were related to worse performance in men, but not women. Higher cortisol levels were also related to lower word recall, but only in men. Finally, men, but not women, had higher switching costs in the Trail Making task as levels of sAA rose. The results provide evidence that sex moderates the stress biomarker-cognition relationship in a variety of cognitive outcomes. Although not part of the primary analysis, sAA and cortisol interacted such that increased sAA levels were only negatively related to backward counting performance when cortisol levels were low. The findings are discussed primarily in terms of biological sex differences in the stress response.     

Gender differences in episodic memory and visual working memory including the effects of age

Analysing the relationship between gender and memory, and examining the effects of age on the overall memory-related functioning, are the ongoing goals of psychological research. The present study examined gender and age group differences in episodic memory with respect to the type of task. In addition, these subgroup differences were also analysed in visual working memory. A sample of 366 women and 330 men, aged between 16 and 69 years of age, participated in the current study. Results indicate that women outperformed men on auditory memory tasks, whereas male adolescents and older male adults showed higher level performances on visual episodic and visual working memory measures. However, the size of gender-linked effects varied somewhat across age groups. Furthermore, results partly support a declining performance on episodic memory and visual working memory measures with increasing age. Although age-related losses in episodic memory could not be explained by a decreasing verbal and visuospatial ability with age, women's advantage in auditory episodic memory could be explained by their advantage in verbal ability. Men's higher level visual episodic memory performance was found to result from their advantage in visuospatial ability. Finally, possible methodological, biological, and cognitive explanations for the current findings are discussed.     

Effects of working memory training in young and old adults

Many cognitive abilities, including working memory and reasoning ability, decline with progressing age. In this study, we investigated whether four weeks of intensive working memory training would enhance working memory and reasoning performance in an age-comparative setting. Groups of 34 young (19–36 years) and 27 older (62–77 years) adults practiced tasks representing the three functional categories in the facet model of working memory capacity: storage and processing, relational integration, and supervision. The data were compared to those of a young and an old active control group who practiced tasks with low working memory demands. A cognitive test battery measuring near and far transfer was administered before and after training. Both age groups showed increased working memory performance in the trained tasks and in one structurally similar, but nontrained, task. Young adults also improved in a task measuring word-position binding in working memory. However, we found no far transfer to reasoning in either age group. The results provide evidence that working memory performance can be improved throughout the life span. However, in contrast to a previous study in which each facet of working memory capacity was trained separately, the present study showed that training multiple functional categories simultaneously induces less transfer.     

Do pulmonary function and smoking behavior predict cognitive function? findings from a british sample

Abstract

The relationship of smoking behavior, pulmonary function, and four measures of cognitive function was studied in a sample of 4,399 men and women (mean age = 44.7 f 17.1 years; age range: 18 to 94 years) randomly selected from British electoral registers. Each subject was assessed with a face-to-face structured interview (including demographic data, smoking history, and health-related questions) as well as cognitive testing [simple reaction time (SRT), choice reaction time (CRT), incidental memory, and spatial reasoning] and pulmonary function testing. Results indicated that smoking was associated with somewhat better performance on the CRT and memory tasks, and that smoking behavior was not associated with decrements in cognitive performance. Impaired pulmonary function was generally associated with poorer cognitive performance on all of the cognitive measures, suggesting that pulmonary function may be a relevant factor to consider in experimental studies of smoking and cognitive function among healthy adults.     

The impact of physical activity and sex differences on intraindividual variability in inhibitory performance in older adults

It is well-known that processing speed and executive functions decline with advancing age. However, physical activity (PA) has a positive impact on cognitive performances in aging, specifically for inhibition. Less is known concerning intraindividual variability (iiV) in reaction times. This study aims to investigate the influence of PA and sex differences on iiV in inhibitory performance during aging. Healthy adults were divided into active and sedentary groups according to PA level. To analyse iiV in reaction times, individual mean, standard deviation and the ex-Gaussian parameters were considered. An interaction between activity level and sex was revealed, sedentary females being slower and more variable than sedentary men. No sex differences were found in the active groups. These results indicate that the negative impact of sedentariness on cognitive performance in older age is stronger for females. The present findings underline the need to consider sex differences in active aging approaches.     

Improving aerobic capacity in healthy older adults does not necessarily lead to improved cognitive performance

The effects of aerobic exercise training in a sample of 85 older adults were investigated. Ss were assigned randomly to either an aerobic exercise group, a nonaerobic exercise (yoga) group, or a waiting-list control group. Following 16 weeks of the group-specific protocol, all of the older Ss received 16 weeks of aerobic exercise training. The older adults demonstrated a significant increase in aerobic capacity (cardiorespiratory fitness). Performance on reaction-time tests of attention and memory retrieval was slower for the older adults than for a comparison group of 24 young adults, and there was no improvement in the older adults' performance on these tests as a function of aerobic exercise training. Results suggest that exercise-related changes in older adults' cognitive performance are due either to extended periods of training or to cohort differences between physically active and sedentary individuals.     

Type of physical exercise and inhibitory function in older adults: An event-related potential study

ObjectivesThe present study was to examine the relationship between exercise type and inhibitory function in older adults using neuroelectric indices.DesignA cross-sectional design was employed in the present study.MethodSixty adults (M = 69.42 years) were categorized into open-skill, closed-skill, and irregular exercise groups according to their history of exercise participation. The participants conducted a flanker task while their behavioral performance and event-related brain potentials were assessed.ResultsThe results indicated that regular exercisers, regardless of exercise type, exhibited a faster reaction time across conditions of the flanker task compared to irregular exercisers. For the P300 amplitude of the open-skill exerciser group, the peak amplitude was larger at the vertex site compared to the frontal site, whereas no site differences were observed in the closed-skill and irregular exerciser groups.ConclusionsThese findings extend current knowledge by suggesting that, for older adults, participation in physical exercise involving increased cognitive demand is associated with better neural efficiency in resource allocation for tasks that require interference control.     

Cognitive and Psychosocial Consequences of Hurricanes Katrina and Rita Among Middle-Aged, Older, and Oldest-Old Adults in the Louisiana Healthy Aging Study (LHAS)

This study examined the impact of Hurricanes Katrina and Rita on cognitive and psychosocial functioning among middle-aged (45-64 years), older (65-89 years) and oldest-old adults (90 years and over) in the Louisiana Healthy Aging Study (LHAS). Analyses of pre- and post-disaster cognitive data showed storm-related decrements in working memory for the middle-aged and older adults, but not for the oldest-old adults. Regression analyses confirmed that measures of social engagement and storm-related disruption significantly predicted pre- to post-disaster differences in short-term and working memory performance for the middle-aged and older adults only. These results are consistent with a burden perspective on post-disaster psychological reactions. Implications for current views of disaster reactions are discussed.     

Cognitive functioning of older people in relation to social and personality variables

Age differences in performance on memory measures and in subjective ratings of memory adequacy were examined in the context of 12 social, personality, adjustment, and lifestyle measures. Participants were 285 men and women, aged 65 to 93, of middle- and working-class backgrounds. A series of multivariate and univariate analyses revealed that a large proportion of the age differences and virtually all of the social-class differences on memory measures could be accounted for by contextual variables, with education, intellectual activity, extroversion, neuroticism, and lie scores (on the Eysenck Personality Inventory) all accounting for more of the variance in memory performance than did age. Self-rated memory adequacy was not correlated with performance, and although the expected finding of lower ratings by older participants was obtained with the working-class group, the opposite was true for the middle-class group. Implications of these results for understanding age differences in memory are discussed.     

Exercise type relates to inhibitory and error processing functions in older adults

ABSTRACT

This study investigated the association between exercise type and inhibition of prepotent responses and error detection. Totally, 75 adults (M = 68.88 years) were classified into one of three exercise groups: those who were regular participants in open- or closed-skill forms of exercise, and those who exercised only irregularly. The participants completed a Stroop and task-switching tasks with event-related brain potentials (ERPs) recorded. The results revealed that regular exercisers displayed faster reaction times (RTs) in the Stroop task compared with irregular exercisers. The open-skill exercisers exhibited smaller N200 and larger P300a amplitudes in the Stroop task compared with irregular exercisers. Furthermore, the open-skill exercisers showed a tendency of shorter error-related negativity latencies at the task-witching test. The findings suggest that older adults may gain extra cognitive benefits in areas such as inhibition functioning and error processing from participating in open-skill forms of physical exercises.     

Components of quantitative reasoning: General and group ability factors

In this study we tested the hypothesis that quantitative reasoning performance is a function of specific processing components as well as general cognitive abilities such as working memory capacity, reasoning, and verbal comprehension. Subjects were administered tests of these three ability factors as well as tests designed to measure three components thought to underlie algebra word problem solving: problem-type identification, decomposition and sequencing, and problem translation. Confirmatory factor analyses indicated good fits for our models of the general ability factors and the word-problem-solving components. Further analyses indicated that the word-problem-solving components added substantially to the more general cognitive abilities in explaining variance in arithmetic reasoning and math knowledge test scores obtained from the Armed Services Vocational Aptitude Battery. We conclude that although general cognitive ability and/or working memory are certainly important ingredients of quantitative reasoning, specific processing components suggested by cognitive theory are at least as important determinants of performance.     

Effects of adult age and working memory on reasoning and spatial abilities

Three predictions were derived from the hypothesis that adult age differences in certain measures of cognitive functioning are attributable to age-related reductions in a processing resource such as working-memory capacity. Each prediction received at least some degree of empirical support in a study involving 120 males ranging between 20 and 79 years of age. First, older adults exhibited greater impairments of performance than did young adults when task complexity increased and more demands were placed on the limited processing resources; second, the magnitudes of these complexity effects were highly correlated across verbal (reasoning) and spatial (paper folding) tasks. Finally, statistical control of an index of a working-memory processing resource attenuated the effects of age on the measures of cognitive performance. It was concluded that further progress in understanding the mechanisms of the relation between age and cognitive functioning will require improved conceptualizations of the nature of working memory or other hypothesized mediating constructs.     

Exercise, pain, perceived family support, and quality of life in Korean patients with ankylosing spondylitis

Relations of habitual exercise and pain, perceived family support, and the quality of life in patients with functional class II for ankylosing spondylitis were explored. In a cross-sectional study perceived pain, family support, and quality of life were compared for 30 patients (23 women and 7 men whose mean age was 28.3 yr.+/-8.6 yr.) practicing exercise regularly and for 38 sedentary patients (31 women and 7 men whose mean age was 27.2+/-6.7 yr.). Exercising patients reported significantly lower pain, greater perceived family support, and increased quality of life than their sedentary peers. Pain ratings were significantly negatively correlated with the quality of life in both groups (r = -.26 in exercisers and r = -.50 in sedentary patients) and control group's perceived family support was significantly correlated .44 with quality of life. These results encourage further study of the associations of habitual exercise with perceived pain, family support, and quality of life.     

Sex differences in theory of mind: A male advantage on Happé's “cartoon” task

It is a commonly held stereotype that women show superior performance on tests of social cognition such as face processing and theory of mind (ToM) compared to men. However, such purported differences have not been empirically tested. In this study 40 healthy men and 40 women matched for age and years of education completed a well-known experimental ToM test requiring the attribution of either physical or mental states (Happé's cartoon task). Men showed superior performance compared to women, with a medium effect size, on both the mental state and physical state cartoons. It is suggested that men may use a cognitive systemising strategy during these tasks. The results emphasise the task-specific nature of sex differences in social cognition and necessitate future work to elucidate individual differences at the interface of cognitive and affective processes.     

Reasoning strategies: the role of working memory and verbal-spatial ability

Evidence increasingly suggests individual differences in strategies adopted on reasoning tasks and that these are either verbal-propositional or visuospatial in nature. However, the cognitive foundations of these strategies remain uncertain. Experiment 1 examined the relationship between the use of working memory resources and strategy selection for syllogistic reasoning. Verbal and spatial strategy users did not differ on working memory capacity, but confirmatory factor analysis indicated that while verbal reasoners draw primarily on verbal working memory, spatial reasoners use both this and spatial resources. Experiment 2 investigated the relationship between strategies and verbal and spatial abilities. Although strategy groups were similar in overall ability, regression analysis showed that performance on a spatial ability measure (Vandenberg mental rotation task) predicted syllogistic reasoning performance, but only for spatial strategy users. The findings provide converging evidence that verbal and spatial strategies are underpinned by related differences in fundamental cognitive factors, drawing differentially on the subcomponents of working memory and on spatial ability.     

The role of planning in different mathematical skills

Despite the fact that planning has been found to be a significant predictor of reading (particularly of reading comprehension), much less is known about its contribution to mathematics. The purpose of this study was to examine the role of two levels of planning (operation planning and action planning) in three mathematical skills (calculation fluency, math problem-solving, and math reasoning). Eighty Grade 2 children from Shanghai, China were assessed on measures of nonverbal cognitive ability (nonverbal matrices), working memory (digit span backwards and N-back), operation planning (matching numbers, planned codes, and planned search), action planning (crack the code), and mathematics (calculation fluency, math problem-solving, and math reasoning). The results of regression analyses showed that both levels of planning accounted for unique variance in mathematics over and above the effects of nonverbal cognitive ability and working memory. The effects of action planning were particularly strong in math problem-solving. These findings suggest that measures of planning could be used along with measures of working memory to detect children at-risk for mathematics disabilities and that intervention programmes targeting planning could be developed to boost children's mathematics performance.     

Intraindividual variability may not always indicate vulnerability in elders' cognitive performance

This study examined consistency of performance, or intraindividual variability, in older adults' performance on 3 measures of cognitive functioning: inductive reasoning, memory, and perceptual speed. Theoretical speculation has suggested that such intraindividual variability may signal underlying vulnerability or neurologic compromise. Thirty-six participants aged 60 and older completed self-administered cognitive assessments twice a day for 60 consecutive days. Intraindividual variability was not strongly correlated among the 3 cognitive measures, but, over the course of the study, intraindividual variability was strongly intercorrelated within a task. Higher average performance on a measure was associated with greater performance variability, and follow-up analyses revealed that a higher level of intraindividual variability is positively associated with the magnitude of a person's practice-related gain on a particular measure. The authors argue that both adaptive (practice-related) and maladaptive (inconsistency-related) intraindividual variability may exist within the same individuals over time.