Characteristics of the Florida cognitive activities scale in older African Americans

Substantial research effort has recently focused on the potential protective effect of cognitively demanding activities on cognitive decline in late life. A significant methodological issue in this effort has been the lack of consistency in approaches to the operational measurement of cognitive activity. In this study, data in support of the reliability and construct validity of the recently developed Florida Cognitive Activities Scale (FCAS) in a sample of 223 African American older adults are provided. Consistent with the findings of the Schinka et al. study using a sample of Whites, the FCAS full scale showed a reasonably high level of internal consistency, small negative correlations with age and a measure of depressive symptomatology, and moderate positive correlations with years of education and neuropsychological measures of overall cognitive functioning, memory, and executive functioning. Even after controlling for the effects of age, education, and gender, the full scale score contributed significantly to the prediction of global cognitive functioning. The results of this study suggest that the FCAS is a reliable and valid measure of cognitive activities in older African Americans and provides additional, although not causative, evidence in support of the hypothesis of a protective effect of cognitive activity against cognitive decline regardless of ethnicity or race.     

The relation of hypertension to cognitive function

Hypertension is an established risk factor for stroke. However, prior to such a major clinical event, hypertension exerts a more subtle impact on the brain that is revealed by diminished cognitive function. Studies comparing the performance of people with high and normal blood pressure levels have shown that high blood pressure or hypertension is related to poorer performance on tests of attention, learning and memory, executive functions, visuospatial skills, psychomotor abilities, and perceptual skills. Hypertension is also predictive of cognitive decline. Variables that may alter (i.e., moderate) the relation of hypertension to cognitive function include age, education, several biological characteristics of hypertension, and the presence of concurrent diseases. Although hypertensives are not clinically impaired, their diminished levels of cognitive performance could affect their perceived quality of life. Various brain mechanisms may explain the relation of hypertension to lower levels of cognitive function. Further understanding of the relation between hypertension and cognition is critical to the preservation of cognitive function across the life span.     

Cardiovascular reactivity and central adiposity in older African Americans.

This study examined central adiposity, as measured by waist circumference (WC), in relation to mental-stress induced systolic (SBP) and diastolic blood pressure (DBP) and heart rate (HR) responses, body composition, the metabolic syndrome, and health practices in 22 older, African American men and women (ages 52-79 years). The high WC (> 100 cm) group showed significantly greater SBP, DBP, and HR reactivity, greater fasting insulin levels, lower high density lipoprotein cholesterol levels, greater fat mass in both truncal and peripheral regions, and greater body mass index as compared to the low WC (< 100 cm) group. Groups were comparable with respect to fat-free mass, peak oxygen consumption (VO2), leisure time activity, dietary intake, resting blood pressure, and other metabolic variables. The findings support a clustering of metabolic and mental stress risk factors that may predispose older African Americans to increased cardiovascular and metabolic disease.     

A belief in trend reversal requires access to cognitive resources

There are two research traditions studying people's reactions to random binary events: one concerns serial choice reaction times, the other concerns predictions of events in a series. The present studies focused on comparing expectations between these two approaches. We formed and tested a general hypothesis that, regardless of the type of task, when an individual faces a sequence of events they initially expect trend continuation. Only when people assume that a sequence is random might they override the default and expect trend reversal instead. In a series of experiments we found that limitation of access to cognitive resources enhances expectations of trend continuation. Our interpretation of this finding is that an expectation of trend continuation is the default for the human cognitive system and that a belief in trend reversal requires access to cognitive resources to overcome the tendency to expect trend continuation.     

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.     

Physical activity and cognitive function in a cross-section of younger and older community-dwelling individuals.

Previous reports have indicated a small, positive relationship between physical activity and cognition. However, the majority of research has focused on older adults, with few studies examining this relationship during earlier periods of the life span. This study examined the relationship of physical activity to cognition in a cross-section of 241 community-dwelling individuals 15-71 years of age with a task requiring variable amounts of executive control. Data were analyzed with multiple regression, which controlled for age, sex, and IQ. Participants reported their physical activity behavior and were tested for reaction time (RT) and response accuracy on congruent and incongruent conditions of a flanker task, which manipulates interference control. After controlling for confounding variables, an age-related slowing of RT was observed during both congruent and incongruent flanker conditions. However, physical activity was associated with faster RT during these conditions, regardless of age. Response accuracy findings indicated that increased physical activity was associated with better performance only during the incongruent condition for the older cohort. Findings suggest that physical activity may be beneficial to both general and selective aspects of cognition, particularly among older adults.     

Subjective cognitive complaint in healthy older adults: Identification of major domains and relation to objective performance

This study analyzed complaints across a range of memory domains in middle-aged and older adults, as well as assessed their relationship with objective cognitive performance and personal characteristics. A total of 115 community-dwelling, healthy adults between the ages of 45 and 87 completed the Self-Evaluation Questionnaire (QAM) and were tested with a comprehensive neuropsychological battery. A principal component analysis identified seven dimensions of complaint. Difficulty inhibiting internal and external sources of interference when learning or remembering something was the main area of complaint and it was correlated with word-list recall and Digit Symbol. We identified complaints related to a set of memory failures that appear to be more detrimental to autonomy and safety. These were correlated with a measure of functional autonomy and might, therefore, indicate more severe difficulties. Overall, this study provides indications regarding the main domains of memory complaints and identifies which complaints are most reflective of objective cognitive problems.     

Different perspectives on measuring lifestyle engagement: a comparison of activity measures and their relation with cognitive performance in older adults

Given the limitations associated with assessing activity engagement via the frequency of specific activities, it may be valuable to consider the characteristics of an activity. The method of asking individuals to report the amount of time spent engaging in activities that have certain characteristics was compared to a specific activity questionnaire, and a daily diary regarding their relation to cognitive functioning. Participants 60–90 years old (n = 187) completed the activity measurement methods and a series of cognitive tasks. Structural equation models showed that all three activity methods were predictive of adults’ cognitive performance, but no measure predicted all outcomes. Each activity measure provided unique information. Notably, the combination of the measurement types predicted more variance than any of the measures alone. There is additional power to predict cognition when multiple activity measurement methods are used, and daily assessment can be a valuable tool to augment traditional specific activity questionnaires.     

Saccadic eye movements as indicators of cognitive function in older adults

Older adults appear to have greater difficulty ignoring distractions during day-to-day activities than younger adults. To assess these effects of age, the ability of adults aged between 50 and 80 years to ignore distracting stimuli was measured using the antisaccade and oculomotor capture tasks. In the antisaccade task, observers are instructed to look away from a visual cue, whereas in the oculomotor capture task, observers are instructed to look toward a colored singleton in the presence of a concurrent onset distractor. Index scores of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) were compared with capture errors, and with prosaccade errors on the antisaccade task. A higher percentage of capture errors were made on the oculomotor capture tasks by the older members of the cohort compared to the younger members. There was a weak relationship between the attention index and capture errors, but the visuospatial/constructional index was the strongest predictor of prosaccade error rate in the antisaccade task. The saccade reaction times (SRTs) of correct initial saccades in the oculomotor capture task were poorly correlated with age, and with the neurospsychological tests, but prosaccade SRTs in both tasks moderately correlated with antisaccade error rate. These results were interpreted in terms of a competitive integration (or race) model. Any variable that reduces the strength of the top-down neural signal to produce a voluntary saccade, or that increases saccade speed, will enhance the likelihood that a reflexive saccade to a stimulus with an abrupt onset will occur.     

Cognitive reserve and cognitive function in healthy older people: a meta-analysis

The associations between proxy measures of cognitive reserve (CR) and cognition vary across studies and cognitive domains. This meta-analysis aimed to assess the relationship between CR and cognition in multiple domains (memory, executive function, visuospatial ability, and language). CR was considered in terms of three key proxy measures – educational level, occupational status, and engagement in cognitively stimulating activities – individually and in combination. One-hundred and thirty-five studies representing 128,328 participants were included. Of these, 109 used a measure of education, 19 used a measure of occupation, 31 used a measure of participation in cognitively stimulating activities, and 6 used a combination of these. All three proxy measures had a modest positive association with cognition; occupational status and cognitive activities showed the most variation across cognitive domains. This supports the view that the commonly used proxy measures of CR share an underlying process but that each additionally provides a unique contribution to CR.     

The impact of aerobic activity on cognitive function in older adults: A new synthesis based on the concept of executive control

Numerous reaction time studies have suggested that age-related declines in cognitive function might be ameliorated by lifestyles involving aerobic activity or by interventionist programmes of aerobic exercise. These studies are far from conclusive, however, reflecting a failure to factor out cognitive from sensory and motor processes. Following a critical review of the literature, we report on recent developments that differentiate cognitive processes involving executive vs non-executive control, the former being associated with frontal lobe function. Three key studies suggest that aerobic exercise primarily improves executive control.     

Plasma anticholinergic activity and cognitive function in geriatric patients

This study evaluated the putative impact of circulating anticholinergic equivalents on cognitive functional performance in non-demented geropsychiatric inpatients. Standard rating instruments were administered to measure memory functions, concentration and overall functional competency. Anticholinergic plasma activity was assayed, using a radioreceptor technique with tritiated quinuclidinyl benzilate as the active reagent. None of the cognitive tests employed indicated a statistically significant change in the subjects' quantifiable level of cognitive performance. All changes in anticholinergic activities were related to adjustments in psychotherapeutic medications. The possible role of reversal of pseudodementing features is discussed as well as the potential for monitoring anticholinergic activity when treating elderly individuals with more than one centrally active medication having anticholinergic properties.     

Comparison of age and time-to-death in the dedifferentiation of late-life cognitive abilities

The dedifferentiation hypothesis proposes that specific cognitive abilities become more highly associated with general ability in old age as a result of increasing biological constraints on fluid intelligence. There is limited evidence for the hypothesis, and research has not tended to clearly distinguish age dedifferentiation from ability differentiation and other age-related phenomena. The present study examined age dedifferentiation using a structural equation model that controlled for ability differentiation, along with linear and quadratic effects of age. Time-to-death was examined as an alternative time metric to chronological age, as it may better represent biological constraints. The Canberra Longitudinal Study community-based cohort, consisting of 896 Australian adults aged 70 and over, provided data from 687 decedents who were followed for up to 17 years. Results indicated little support for the age dedifferentiation hypothesis, with only two of seven cognitive tests showing significant age dedifferentiation. The time-to-death metric showed more evidence of dedifferentiation, with four of the seven tests exhibiting dedifferentiation. However, after excluding participants with possible cognitive impairment, all of the dedifferentiation effects were attenuated to nonsignificance. Age dedifferentiation effects may therefore reflect dementia and other mortality-related pathology rather than being an inevitable outcome of advanced age. Alternative developmental theories for cognitive function must better account for the diversity of late-life abilities and pathology.     

The Impact of Religiosity on Substance Abuse and Obesity in African Americans

Among the African American community, there exist many health disparities which warrant greater examination through the practice of social work. The aim of the present research was to explore the impact of religiosity on substance abuse and obesity among African American populations by employing a systematic review of the current body of literature on this subject. While many of the studies reviewed found at least a weak relationship between religiosity and obesity, such results were not consistent across all materials examined. Among those studies that found a correlation between these factors, many demonstrated that religiosity had a positive impact on substance abuse and obesity. A discussion of the implications of these findings is submitted as a means of illuminating the significance of all research findings that were examined. Limitations such as more standardized criteria for inclusion of research material are identified and discussed. Implications for future research are presented to promote the advancement of future efforts in this area research.     

Volunteering in older adulthood is associated with activity engagement and cognitive functioning

ABSTRACT

Introduction: Given evidence that activity engagement in older adulthood can have protective effects on the aging brain, we investigated the idea that volunteering in the community, which often encompasses social, cognitive, and physical activity, might benefit cognition.

Method: Ninety-one retired 65- to 75-year-olds reported their sociodemographic characteristics, wellbeing, volunteering, and activity engagement. They also completed computerized cognitive tests that tapped specific functions known to decline disproportionately with age.

Results: Volunteering at least monthly was associated with better working memory and more social and cognitive activity. Mediation analyses indicated that volunteering was indirectly related to switching performance via cognitive activity. However, the volunteering-working memory association did not depend on activity engagement, leaving the underpinning mechanisms unclear.

Conclusions: These findings provide new insight into positive associations between older people’s volunteering, activity engagement, and cognitive functioning. However, further work is needed to understand the mechanisms that drive volunteering-cognition links, and to establish causality.