Inconsistency in serial choice decision and motor reaction times dissociate in younger and older adults

Intraindividual variability (inconsistency) in reaction time (RT) latencies was investigated in a group of younger (M=25.46 years) and older (M=69.29 years) men. Both groups performed 300 trials in 2-, 4-, and 8-choice RT conditions where RTs for decision and motor components of the task were recorded separately. A dissociation was evident in that inconsistency was greater in older adults for decision RTs when task demands relating to the number of choices and fatigue arising from time-on-task were high. For younger persons, a weak trend toward greater inconsistency in motor RTs was evident. The results are consistent with accounts suggesting that inconsistency in neurobiological mechanisms increases with age, and that attentional lapses or fluctuations in executive control contribute to RT inconsistency.     

Age-related effects of blood pressure on everyday cognitive function in community-dwelling women

ABSTRACT

Objectives: Blood pressure is an indicator of vascular health that has been associated with cognition and quality of life in older age. Few studies have examined blood pressure across everyday cognitive tasks, which may have superior predictive functional utility than traditional cognitive measures. We explored blood pressure as a predictor of everyday problem solving (EPS) performance in middle-aged and older women. Method: Community-dwelling women (age: 51–91) with low-normal blood pressure to mild hypertension underwent traditional and everyday cognitive testing. EPS was determined by the number of safe/effective solutions generated for real-world scenarios. Results: Analyses revealed that lower systolic blood pressure and pulse pressure were associated with worse EPS ability after controlling for age, education, and traditional cognitive abilities. Discussion: These results support that blood pressure may be an important predictor of everyday cognitive abilities in older age. Potential implications for real-world functioning are discussed.     

Self-Reported Cognitive Inconsistency in Older Adults

ABSTRACT

Insight into one's own cognitive abilities, or metacognition, has been widely studied in developmental psychology. Relevance to the clinician is high, as memory complaints in older adults show an association with impending dementia, even after controlling for likely confounds. Another candidate marker of impending dementia under study is inconsistency in cognitive performance over short time intervals. Although there has been a recent proliferation of studies of cognitive inconsistency in older adults, to date, no one has examined adults' self-perceptions of cognitive inconsistency. Ninety-four community-dwelling older adults (aged 70–91) were randomly selected from a parent longitudinal study of short-term inconsistency and long-term cognitive change in aging. Participants completed a novel 40-item self-report measure of everyday cognitive inconsistency, including parallel scales indexing perceived inconsistency 5 years ago and at present, yielding measures of past, present, and 5-year change in inconsistency. The questionnaire showed acceptable psychometric characteristics. The sample reported an increase in perceived inconsistency over time. Higher reported present inconsistency and greater 5-year increase in inconsistency were associated with noncognitive (e.g., older age, poorer ADLs, poorer health, higher depression), metacognitive (e.g., poorer self-rated memory) and neuropsychological (e.g., poorer performance and greater 5-year decline in global cognitive status, vocabulary, and memory) measures. Correlations between self-reported inconsistency and neuropsychological performance were attenuated, but largely persisted when self-rated memory and age were controlled. Observed relationships between self-reported inconsistency and measures of neuropsychological (including memory) status and decline suggest that self-perceived inconsistency may be an area of relevance in evaluating older adults for memory disorders.     

Reaction Time Inconsistency in a Spatial Stroop Task: Age-Related Differences Through Childhood and Adulthood

ABSTRACT

Age-related differences in inconsistency of reaction time (RT) across the life span were examined on a task with differing levels of demand on executive control. A total of 546 participants, aged 5 to 76 years, completed a spatial Stroop task that permitted observations under three conditions (congruent, incongruent, and neutral) according to the correspondence between the required response (based on stimulus direction) and stimulus location. An interference effect was observed across all ages. Analyses of neutral condition data replicated previous research demonstrating RT inconsistency follows a U-shaped developmental curve across the life span. The relationship between age and inconsistency, however, depended on condition: inconsistency in the congruent condition was higher than inconsistency in both the neutral and incongruent conditions across middle-aged groups. Reaction time inconsistency may reflect processing efficiency that is maximal in young adulthood and may also be sensitive to fluctuations in performance that reflect momentarily highly efficient responding.     

Relationships among health factors and everyday problem solving in african americans.

This study examined whether measures of health status enhance the prediction of performance on everyday problem solving in adult African Americans. The sample consisted of 209 community-dwelling African American adults with a mean age of 66.82 years (SD=7.95). The following variables were included in the analysis: Everyday Problems Test (EPT), summary index of chronic illnesses (cardiovascular disease, hypertension, arthritis, stroke, and diabetes), self-rated health (current health, health in the past month, health compared with others, health compared with 5 years ago), and demographic information. Using hierarchical regression and follow-up communality analysis, the authors found that the number of chronic illnesses and self-rated health as compared with 5 years prior were significant and unique predictors of performance on the EPT but did not account for all of the demographic-related variance. The results indicate that health indices contribute to the variability in everyday cognition in this understudied population.     

Goals and Everyday Problem Solving: Examining the Link between Age-Related Goals and Problem-Solving Strategy Use

ABSTRACT

Qualitative interviews on family and financial problems from 332 adolescents, young, middle-aged, and older adults, demonstrated that developmentally relevant goals predicted problem-solving strategy use over and above problem domain. Four focal goals concerned autonomy, generativity, maintaining good relationships with others, and changing another person. We examined both self- and other-focused problem-solving strategies. Autonomy goals were associated with self-focused instrumental problem solving and generative goals were related to other-focused instrumental problem solving in family and financial problems. Goals of changing another person were related to other-focused instrumental problem solving in the family domain only. The match between goals and strategies, an indicator of problem-solving adaptiveness, showed that young individuals displayed the greatest match between autonomy goals and self-focused problem solving, whereas older adults showed a greater match between generative goals and other-focused problem solving. Findings speak to the importance of considering goals in investigations of age-related differences in everyday problem solving.     

Exploring collaborative problem solving in adulthood

Collaborative problem solving occurs in situations in which two or more individuals cooperate in appraising, representing, and solving a variety of cognitive tasks. Collaborative groups are the context for much everyday cognitive activity in adulthood. Collaboration has been explored as a means through which older adults may maintain high levels of performance, perhaps compensating for individual-level cognitive and neurological decline. This study explored the effects of collaboration (group size) and adult age on solving both fixed- and unrestricted-alternatives 20 Questions tasks. Younger (M=24.3 years) and older (M=67.9 years) adults were randomly assigned to one of three homogeneous group size conditions: individuals, dyads, and tetrads. Results indicated some dissociation between individual-level performance (poorer for older adults) and collaborative performance (better for older adults). For the fixed-alternatives task, older adults produced more of the relatively inefficient hypothesis-scanning questions than did younger adults. In contrast, older collaborative groups produced more of the efficient constraint-seeking questions than hhpothesis-scanning questions, and an amount equivalent to that of younger adults. Overall performance for the difficult unrestricted-alternatives task was less efficient for both younger and older adults. The roles of task type, group characteristics, and adult age are discussed.     

Age Differences in Day-To-Day Speed-Accuracy Tradeoffs: Results from the COGITO Study

We examined adult age differences in day-to-day adjustments in speed-accuracy tradeoffs (SAT) on a figural comparison task. Data came from the COGITO study, with over 100 younger and 100 older adults, assessed for over 100 days. Participants were given explicit feedback about their completion time and accuracy each day after task completion. We applied a multivariate vector auto-regressive model of order 1 to the daily mean reaction time (RT) and daily accuracy scores together, within each age group. We expected that participants adjusted their SAT if the two cross-regressive parameters from RT (or accuracy) on day t-1 of accuracy (or RT) on day t were sizable and negative. We found that: (a) the temporal dependencies of both accuracy and RT were quite strong in both age groups; (b) younger adults showed an effect of their accuracy on day t-1 on their RT on day t, a pattern that was in accordance with adjustments of their SAT; (c) older adults did not appear to adjust their SAT; (d) these effects were partly associated with reliable individual differences within each age group. We discuss possible explanations for older adults’ reluctance to recalibrate speed and accuracy on a day-to-day basis.     

Neuropsychological mediators of the links among age, chronic illness, and everyday problem solving

Reductions in everyday problem solving (EPS) are often reported in older age, although the underlying mechanisms remain unclear. The authors examined the role of 2 variables predicted to mediate (neuropsychological abilities and health status) or moderate (health status) the relationship between age and EPS performance. Toward these ends, they compared EPS and neuropsychological performance in 50 functionally independent adults with chronic kidney disease (CKD) and 64 control participants matched on age and education. Both older age and CKD were associated with worse performance on measures of EPS and memory/executive abilities. Neuropsychological abilities were positively associated with EPS performance. In both the full sample and control participants only, memory/executive functioning mediated the association between presence of chronic illness and EPS. Furthermore, memory/executive functioning partially mediated the link between age and EPS. Findings indicate that relations among age, health status, and EPS are not straightforward. Although performance on neuropsychological measures appeared to underlie EPS declines in chronic illness, increasing age remained independently associated with reduced EPS. The authors discuss implications for models of adult developmental changes in everyday cognition.     

The Effect of Age on Rule-Based Category Learning

ABSTRACT

An explicit, rule-based, category-learning task with abstract visual stimuli was administered to 50 healthy older adults and 48 younger adults. Accuracy and reaction time (RT) were examined for the effects of age, perceptual abilities, rule memory, rule complexity, stimulus novelty, and response competition. Older adults performed at equivalent levels to younger adults when applying a simple rule, but showed performance decrements when applying a more complex rule. The age effect interacted with both stimulus novelty and response competition, and was not eliminated after controlling for basic perceptual abilities and rule memory. The authors suggest that older adults show category learning deficits in conditions that require enhanced cognitive control. These results are discussed in reference to the growing body of literature regarding age-related change in executive abilities and frontal lobe function.     

Effect of imagery ability on letter-level and word-level processing

In a letter-identification task, subjects matched a probe letter to the initial letter of a subsequently presented probe word. We varied word frequency and predicted that the performance of vivid imagers would resemble that of typical young adults, whereas the performance of poor imagers would fall in between that of typical young adults and of older adults, or would simply resemble the performance of typical older adults (a linear decrease in reaction time [RT] with word frequency; see Allen & Madden, 1989). The in-between function for young and older adults combined predicts a dip in RT for very-high-frequency words compared to medium-high-, low-, and very-low-frequency words. As predicted, vivid imagers exhibited increased latencies for medium-high-frequency words relative to the other three word-frequency categories, whereas poor imagers exhibited a dip.     

Performance variability is related to change in cognition: evidence from the Victoria Longitudinal Study

Performance variability across repeated task administrations may be an important indicator of age-related cognitive functioning. In the present investigation, the authors examined whether age differences and change in inconsistency were related to 6-year (3 occasion) cognitive change. Inconsistency scores were computed from 4 reaction time tasks performed by 446 older adults (54-89 years). Replicating previous cross-sectional results, greater inconsistency was observed for older participants even after controlling for differences in response speed. New longitudinal results demonstrated (a) associations between inconsistency at baseline measurement and 6-year change in cognitive performance; (b) longitudinal change in inconsistency; and (c) intraindividual covariation between 6-year change in inconsistency and 6-year change in level of cognitive function. These findings support the view that performance variability serves as a marker of cognitive aging.     

Perceived self-efficacy and everyday problem solving among young and older adults

This research tested the hypothesis that age differences in both self-efficacy perceptions and problem-solving performance would vary as a function of the ecological relevance of problems to young and older adults. The authors developed novel everyday problem-solving stimuli that were ecologically representative of problems commonly confronted by young adults (young-adult problems), older adults (older adult problems), or both (common problems). Performance on an abstract problem solving task lacking in ecological representativeness (the Tower of Hanoi problem) also was examined. Although young persons had higher self-efficacy beliefs and performance levels on the Tower of Hanoi task problem and the young-adult problems, this pattern reversed in the domain of older adult problems, where the self-efficacy beliefs and performance of older persons exceeded those of the young.     

Age and Flexible Thinking: An Experimental Demonstration of the Beneficial Effects of Increased Cognitively Stimulating Activity on Fluid Intelligence in Healthy Older Adults

ABSTRACT

The disuse hypothesis of cognitive aging attributes decrements in fluid intelligence in older adults to reduced cognitively stimulating activity. This study experimentally tested the hypothesis that a period of increased mentally stimulating activities thus would enhance older adults' fluid intelligence performance. Participants (N?=?44, mean age 67.82) were administered pre- and post-test measures, including the fluid intelligence measure, Cattell's Culture Fair (CCF) test. Experimental participants engaged in diverse, novel, mentally stimulating activities for 10–12 weeks and were compared to a control condition. Results supported the hypothesis; the experimental group showed greater pre- to post-CCF gain than did controls (effect size d?=?0.56), with a similar gain on a spatial-perceptual task (WAIS-R Blocks). Even brief periods of increased cognitive stimulation can improve older adults' problem solving and flexible thinking.     

VEP latency and some properties of simple motor reaction-time distribution

Summary The median of simple motor reaction (RT) to a flash parallels the latencies of visually evoked potential (VEP) deflections if flash intensity is varied. However, mean and median reaction times are not equal because of the skewness of RT distribution. It therefore seemed plausible that the mean reaction time — intensity relationship would be steeper than that for VEP latency. Such divergence would account for the intensity-dependent motor component of RT revealed by other psychophysical studies. The latencies of VEP deflections were measured as a function of intensity and the results were compared with mean and median RTs. The difference between mean and median RT is constant and independent of flash intensity. Moreover, both values are parallel to VEP latency. The general pattern of results remains the same after a change in the distribution from which the foreperiod is sampled.     

Everyday problem solving in adulthood and old age

We examined everyday problem solving in adulthood and compared it with traditional measures of cognitive abilities. In the first phase of the research, we describe the construction of an inventory to assess problem solving in situations that adults might encounter in everyday life and examine raters' judgments of effective responses to the problems. In the second phase, adults (N = 126) between the ages of 20 and 78 were administered the inventory and tests of verbal and abstract problem-solving abilities. Results indicated modest but significant positive correlations between performance on the inventory and traditional ability tests. The examination of age differences revealed that performance on the Everyday Problem-Solving Inventory and verbal ability test increased with age, whereas performance on a traditional problem-solving test declined after middle age. In addition, education was unrelated to everyday problem solving, highly related to verbal ability, and moderately related to traditional problem solving. Results are discussed in relation to pluralistic conceptions of intelligence and theories of adult intellectual development.     

Adult Age Differences in Attention to Semantic Context

ABSTRACT

In three experiments age differences in attention to semantic context were examined. The performance of younger adults (ages 18–29 years) and older adults (ages 60–79 years) on a semantic priming task indicated that both age groups could use information regarding the probability that a prime and target would be related to flexibly anticipate the target category given the prime word (Experiment 1). The timing by which target expectancies were reflected in reaction time performance was delayed for older adults as compared to younger adults, but only when the target was expected to be semantically unrelated to the prime word (Experiment 2). When the target and prime were expected to be semantically related, the time course of priming effects was similar for younger and older adults (Experiment 3). Together the findings indicate that older adults are able to use semantic context and the probability of stimulus relatedness to anticipate target information. Although aging may be associated with a delay in the timing by which controlled expectancies are expressed, these findings argue against an age-related decline in the ability to represent contextual information.     

Identification of sensorimotor components accounting for individual variability in Zahlen–Verbindungs-Test (ZVT) performance

The Zahlen–Verbindungs-Test (ZVT) represents a highly feasible measure of information-processing speed that correlates quite highly with standard psychometric tests of intelligence. The present study was designed to identify specific stages of the sensorimotor processing system that may account for individual differences in overall variability of ZVT performance. For this purpose, ZVT, reaction time (RT), lateralized readiness potential (LRP), and electromyogram (EMG) measures were obtained in 48 female participants. While faster RT, smaller intraindividual variability in RT, shorter response-locked LRP and EMG latencies were associated with superior ZVT performance, speed of stimulus analysis, as reflected by stimulus-locked LRP latency, was unrelated to ZVT performance. Additional commonality analyses suggested a functional relationship between ZVT performance and the time course of central aspects of response organization rather than the time required for execution of the overt motor response. These findings provide converging evidence for the general notion of an association between speed of motor processing and intelligence.     

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.     

Aging and Comparative Search for Feature Differences

ABSTRACT

In a comparative visual search experiment, two halves of a display contained visual primitives of various shapes and colors. These halves were identical (50% of trials) or contained a non-matching pair (50% of trials). Response time (RT), accuracy, and eye movements were measured in both young and older adults. There were Age Group × Display Size interactions found for RT, with older adult RT affected more than younger adult RT by increases in display size. This interaction was consistent with predictions generated by sequential-sampling models for RT. There were age group main effects on fixation number and fixation duration, but no age group main effects on accuracy, saccade amplitude, or measures of scan-path efficiency; this indicated that search strategies were similar across age groups. Overall, the results showed no special age group deficits for comparative visual search.