Age-related Differences In Performance Research Articles

Perceptual Learning of Intonation Contour Categories in Adults and 9- to 11-Year-Old Children: Adults Are More Narrow-Minded.

We report on rapid perceptual learning of intonation contour categories in adults and 9- to 11-year-old children. Intonation contours are temporally extended patterns, whose perception requires temporal integration and therefore poses significant working memory challenges. Both children and adults form relatively abstract representations of intonation contours: Previously encountered and novel exemplars are categorized together equally often, as long as distance from the prototype is controlled. However, age-related differences in categorization performance also exist. Given the same experience, adults form narrower categories than children. In addition, adults pay more attention to the end of the contour, while children appear to pay equal attention to the beginning and the end. The age range we examine appears to capture the tail-end of the developmental trajectory for learning intonation contour categories: There is a continuous effect of age on category breadth within the child group, but the oldest children (older than 10;3) are adult-like.

Age-related changes in strategic variations during arithmetic problem solving: The role of executive control.

In this review, we provide an overview of how age-related changes in executive control influence aging effects in arithmetic processing. More specifically, we consider the role of executive control in strategic variations with age during arithmetic problem solving. Previous studies found that age-related differences in arithmetic performance are associated with strategic variations. That is, when they accomplish arithmetic problem-solving tasks, older adults use fewer strategies than young adults, use strategies in different proportions, and select and execute strategies less efficiently. Here, we review recent evidence, suggesting that age-related changes in inhibition, cognitive flexibility, and working memory processes underlie age-related changes in strategic variations during arithmetic problem solving. We discuss both behavioral and neural mechanisms underlying age-related changes in these executive control processes.

Age differences in behavioral and neural correlates of proactive interference: Disentangling the role of overall working memory performance

Reliable performance in working memory (WM) critically depends on the ability to resist proactive interference (PI) from previously relevant WM contents. Both WM performance and PI susceptibility are subject to cognitive decline at older adult age. However, the behavioral and neural processes underlying these co-evolving developmental changes and their potential interdependencies are not yet understood. Here, we investigated PI using a recent-probes WM paradigm and functional MRI in a cross-sectional sample of younger (n=18, 10 female, 23.4±2.7years) and older adults (n=18, 10 female, 70.2±2.7years). As expected, older adults showed lower WM performance and higher PI susceptibility than younger adults. Resolution of PI activated a mainly bilateral frontal network across all participants. Significant interactions with age indicated reduced neural activation in older adults for PI resolution. A second analysis in a selection of younger and older adults (n=12 each) with matched WM performance also revealed significant differences in PI between both age groups and – on a descriptive level – again a hypo-activation of the older adults' PI network. But the differential effect of age on the neural PI effects did not reach significance in this smaller sample most likely to the reduced statistical power. However, given the highly similar patterns in both the overall and the WM-matched samples, we propose that the hypo-activation of the PI network in the older adults may not be attributable to age-related differences in overall WM performance, hence suggesting that higher PI susceptibility in older adult age does not directly depend on their lower WM performance.

Age-related inhibitory deficit, or lack of familiarity benefit? Evidence from letter identification among visual distractors.

Age-related deficits in processing complex visual scenes are often attributed to age-related declines in the cognitive abilities required for such tasks. For example, poorer or slower performance of a complex task in the presence of distractor items is often attributed to an age-related deficit in the ability to inhibit the processing of irrelevant information. To investigate the relative contributions of sensory and cognitive factors in such tasks, younger and older participants were asked to identify a letter presented simultaneously with distractors that were either other letters, pieces of letters, or visual noise controls with identical spatial frequency content or contrast profile. In Experiment 1, older adults performed much worse than younger adults when the masking field consisted of other letters. Surprisingly-and contrary to the predictions of inhibitory deficit or visual "pop-out" phenomena-this effect emerged because younger adults performed much better with letter-containing maskers than with any other type of masker, whereas older adults did not. Experiment 2 revealed that age-related changes in the time required to process the visual display do not appear to account for this effect. In Experiment 3, however, we replicated older adults' task performance in a younger adult sample by filtering the experimental stimuli to match the image contrast typically experienced by an older adult. The results of Experiment 3 suggest that age-related differences in task performance amidst distractors can emerge from age-related declines in contrast sensitivity, which set older adults up to fail at tasks in which younger adults may typically be able to benefit from the familiarity of the target and surrounding objects.

Age-related differences in muscle recruitment and reaction-time performance

Previously, we showed that prolonged reaction-time (RT) in older persons is related to increased antagonist muscle co-activation, occurring already before movement onset. Here, we studied whether a difference in temporal agonist and antagonist muscle activation exists between young and older persons during an RT-test. We studied Mm. Biceps (antagonist muscle) & Triceps (agonist muscle) Brachii activation time by sEMG in 60 young (26±3years) and 64 older (80±6years) community-dwelling subjects during a simple point-to-point RT-test (moving a finger using standardized elbow-extension from one pushbutton to another following a visual stimulus). RT was divided in pre-movement-time (PMT, time for stimulus processing) and movement-time (MT, time for motor response completion). Muscle activation time 1) following stimulus onset (PMAT) and 2) before movement onset (MAT) was calculated. PMAT for both muscles was significantly longer for the older subjects compared to the young (258±53ms versus 224±37ms, p=0.042 for Biceps and 280±70ms versus 218±43ms for Triceps, p<0.01). Longer agonist muscle PMAT was significantly related to worse PMT and RT in young (respectively r=0.76 & r=0.68, p<0.001) and elderly (respectively r=0.42 & r=0.40, p=0.001). In the older subjects we also found that the antagonist muscle activated significantly earlier than the agonist muscle (−22±55ms, p=0.003). We conclude that in older persons, besides the previously reported increased antagonist muscle co-activation, the muscle firing sequence is also profoundly altered. This is characterized by a delayed muscle activation following stimulus onset, and a significantly earlier recruitment of the antagonist muscle before movement onset.

Patterns of frontoparietal activation as a marker for unsuccessful visuospatial processing in healthy aging.

Visuospatial abilities are sensitive to age-related decline, although the neural basis for this decline (and its everyday behavioral correlates) is as yet poorly understood. fMRI was employed to examine age-related differences in patterns of functional activation that underlie changes in visuospatial processing. All participants completed a brief neuropsychological battery and also a figure ground task (FGT) assessing visuospatial processing while fMRI was recorded. Participants included 16 healthy older adults (OA; aged 69-82years) and 16 healthy younger adults (YA; aged 20-35years). We examined age-related differences in behavioral performance on the FGT in relation to patterns of fMRI activation. OA demonstrated reduced performance on the FGT task and showed increased activation of supramarginal parietal cortex as well as increased activation of frontal and temporal regions compared to their younger counterparts. Performance on the FGT related to increased supramarginal gyrus activity and increased medial prefrontal activity in OAs, but not YAs. Our results are consistent with an anterior-posterior compensation model. Successful FGT performance requires the perception and integration of multiple stimuli and thus it is plausible that healthy aging may be accompanied by changes in visuospatial processing that mimic a subtle form of dorsal simultanagnosia. Overall, decreased visuospatial processing in OA relates to an altered frontoparietal neurobiological signature that may contribute to the general phenomenon of increasingly fragmented execution of behavior associated with normal aging.

Strategy and accuracy during information search on the Web: Effects of age and complexity of the search questions

The present study addressed age-related differences in performance and strategies while searching for information on the Web while considering specific processes involved in the search activity on the Internet. To this end, 10 older and 10 younger adults were instructed to use Google to find information. The search questions varied and increased in complexity: three simple questions (participants had to use the keywords provided in the questions), three difficult questions (participants had to infer new keywords to find correct answers), and three impossible questions (no answer existed). The results showed that older participants were less accurate and used fewer efficient strategies compared to younger participants. The differences increased as a function of question complexity. Moreover, older participants tended to focus on the evaluation of the results provided by Google at the expense of opening up and examining websites. In contrast, younger participants controlled their own activities more often, thus allowing them to improve their strategies and obtain higher performances, contrary to older participants who used the same strategies regardless the complexity of the search question.

The Monkey game: A computerized verbal working memory task for self-reliant administration in primary school children.

In two studies, the psychometric properties of an online self-reliant verbal working memory task (the Monkey game) for primary school children (6–12 years of age) were examined. In Study 1, children (n = 5,203) from 31 primary schools participated. The participants completed computerized verbal and visual–spatial working memory tasks (i.e., the Monkey game and the Lion game) and a paper-and-pencil version of Raven’s Standard Progressive Matrices. Reading comprehension and math achievement test scores were obtained from the schools. First, the internal consistency of the Monkey game was examined. Second, multilevel modeling was used to examine the effects of classroom membership. Multilevel multivariate regression analysis was used to examine the Monkey game’s concurrent relationship with the Lion game and its predictive relationships with reading comprehension and math achievement. Also, age-related differences in performance were examined. In Study 2, the concurrent relationships between the Monkey game and two tester-led computerized working memory tasks were further examined (n = 140). Also, the 1- and 2-year stability of the Monkey game was investigated. The Monkey game showed excellent internal consistency, good concurrent relationships with the other working memory measures, and significant age differences in performance. Performance on the Monkey game was also predictive of subsequent reading comprehension and mathematics performance, even after controlling for individual differences in intelligence. Performance on the Monkey game was influenced by classroom membership. The Monkey game is a reliable and suitable instrument for the online computerized and self-reliant assessment of verbal working memory in primary school children.

Comprehensive Assessment of Step Aerobics Exercises Effect on Women’s Physical Performance and Physical Health

Objective: To identify the dynamics of physical performance and physical health indicators in young and middle-aged women under the effect of step aerobics exercises.Material and methods. The grounds for the study were Kharkiv fitness club “Zorianyi”. The participants were 28 women aged 20-35. The study used the following methods: theoretical analysis of scientific and methodical literature, pedagogical experiment, methods of mathematical statistics, methods of determining physical performance (Harvard step test) and physical health (anthropometry, pulsometry, tonometry, spirometry, dynamometry).Results: The study assessed the level of physical performance and physical health; analyzed age-related performance differences; determined the level of the effect of step aerobics on women’s physical performance and physical health.Conclusions: Step-aerobics exercises proved to have a positive effect on the level of physical performance and physical health of the young and middle-aged women.

Receiver operating characteristic analysis of age-related changes in lineup performance

In the basic face memory literature, support has been found for the late maturation hypothesis, which holds that face recognition ability is not fully developed until at least adolescence. Support for the late maturation hypothesis in the criminal lineup identification literature, however, has been equivocal because of the analytic approach that has been used to examine age-related changes in identification performance. Recently, receiver operator characteristic (ROC) analysis was applied for the first time in the adult eyewitness memory literature to examine whether memory sensitivity differs across different types of lineup tests. ROC analysis allows for the separation of memory sensitivity from response bias in the analysis of recognition data. Here, we have made the first ROC-based comparison of adults’ and children’s (5- and 6-year-olds and 9- and 10-year-olds) memory performance on lineups by reanalyzing data from Humphries, Holliday, and Flowe (2012). In line with the late maturation hypothesis, memory sensitivity was significantly greater for adults compared with young children. Memory sensitivity for older children was similar to that for adults. The results indicate that the late maturation hypothesis can be generalized to account for age-related performance differences on an eyewitness memory task. The implications for developmental eyewitness memory research are discussed.

The Effects of Age on the Neural Correlates of Recollection Success, Recollection-Related Cortical Reinstatement, and Post-Retrieval Monitoring.

Functional magnetic resonance imaging (fMRI) was used to investigate whether age-related differences in episodic memory performance are accompanied by a reduction in the specificity of recollected information. We addressed this question by comparing recollection-related cortical reinstatement in young and older adults. At study, subjects viewed objects and concrete words, making 1 of 2 different semantic judgments depending on the study material. Test items were words that corresponded to studied words or the names of studied objects. Subjects indicated whether each test item was recollected, familiar, or novel. Reinstatement of information differentiating the encoding tasks was quantified both with a univariate analysis of the fMRI signal and with a multivoxel pattern analysis, using a classifier that had been trained to discriminate between the 2 classes of study episode. The results of these analyses converged to suggest that reinstatement did not differ according to age. Thus, there was no evidence that specificity of recollected information was reduced in older individuals. Additionally, there were no age effects in the magnitude of recollection-related modulations in regional activity or in the neural correlates of post-retrieval monitoring. Taken together, the findings suggest that the neural mechanisms engaged during successful episodic retrieval can remain stable with advancing age.

Assessment of Age-Related Differences in Functional Capacity Using the Virtual Reality Functional Capacity Assessment Tool (VRFCAT).

Clinical trials for primary prevention and early intervention in preclinical AD require measures of functional capacity with improved sensitivity to deficits in healthier, non-demented individuals. To this end, the Virtual Reality Functional Capacity Assessment Tool (VRFCAT) was developed as a direct performance-based assessment of functional capacity that is sensitive to changes in function across multiple populations. Using a realistic virtual reality environment, the VRFCAT assesses a subject's ability to complete instrumental activities associated with a shopping trip. The present investigation represents an initial evaluation of the VRFCAT as a potential co-primary measure of functional capacity in healthy aging and preclinical MCI/AD by examining test-retest reliability and associations with cognitive performance in healthy young and older adults. The VRFCAT was compared and contrasted with the UPSA-2-VIM, a traditional performance-based assessment utilizing physical props. Results demonstrated strong age-related differences in performance on each VRFCAT outcome measure, including total completion time, total errors, and total forced progressions. VRFCAT performance showed strong correlations with cognitive performance across both age groups. VRFCAT Total Time demonstrated good test-retest reliability (ICC=.80 in young adults; ICC=.64 in older adults) and insignificant practice effects, indicating the measure is suitable for repeated testing in healthy populations. Taken together, these results provide preliminary support for the VRFCAT as a potential measure of functionally relevant change in primary prevention and preclinical AD/MCI trials.

Differences in body composition and physical functions associated with sarcopenia in Chinese elderly: Reference values and prevalence

This study investigates the age-related differences in skeletal muscle mass (SM), muscle strength and physical performance in mainland Chinese. Based on available data, the reference values (criteria) for the definition of sarcopenia in elderly Chinese were explored. Body composition measurements were obtained using a bioelectrical impedance analyzer (BIA); muscle strength was determined by handgrip strength (HS); and physical function was evaluated by the subjects’ 6-m gait speed (GS). In this study, HS and GS declined significantly after 55 years and very dramatically after 75 years. Appendicular SM index of <7.61kg/m2 (males) and <6.43kg/m2 (females); HS of <27kg (males) and <16kg (females); and GS of <0.98m/s (males) and <0.88m/s (females) were considered as low SM, low HS and low GS. Applying these suggested criteria to the study population, there were 9.55% and 6.63% of the subjects with low SM, 20.10% and 18.46% with low GS, and 14.07% and 15.38% with low HS in elderly males and females, respectively. Utilizing Asian Working Group for Sarcopenia (AWGS) criteria in our population results in a very low prevalence of low SM and low GS. If Western criteria for sarcopenia were adopted, the prevalence of low GS and low HS would be 2–4 times higher in the studied population, also exhibiting significant gender differences. These findings indicate that it is necessary to establish an outcomes-based and ethnic-specific set of reference values for the diagnosis of sarcopenia in elderly Chinese.

Structural imaging measures of brain aging.

During the course of normal aging, biological changes occur in the brain that are associated with changes in cognitive ability. This review presents data from neuroimaging studies of primarily "normal" or healthy brain aging. As such, we focus on research in unimpaired or nondemented older adults, but also include findings from lifespan studies that include younger and middle aged individuals as well as from populations with prodromal or clinically symptomatic disease such as cerebrovascular or Alzheimer's disease. This review predominantly addresses structural MRI biomarkers, such as volumetric or thickness measures from anatomical images, and measures of white matter injury and integrity respectively from FLAIR or DTI, and includes complementary data from PET and cognitive or clinical testing as appropriate. The findings reveal highly consistent age-related differences in brain structure, particularly frontal lobe and medial temporal regions that are also accompanied by age-related differences in frontal and medial temporal lobe mediated cognitive abilities. Newer findings also suggest that degeneration of specific white matter tracts such as those passing through the genu and splenium of the corpus callosum may also be related to age-related differences in cognitive performance. Interpretation of these findings, however, must be tempered by the fact that comorbid diseases such as cerebrovascular and Alzheimer's disease also increase in prevalence with advancing age. As such, this review discusses challenges related to interpretation of current theories of cognitive aging in light of the common occurrence of these later-life diseases. Understanding the differences between "Normal" and "Healthy" brain aging and identifying potential modifiable risk factors for brain aging is critical to inform potential treatments to stall or reverse the effects of brain aging and possibly extend cognitive health for our aging society.

Balance decrements are associated with age-related muscle property changes.

In this study, a comprehensive evaluation of static and dynamic balance abilities was performed in young and older adults and regression analysis was used to test whether age-related variations in individual ankle muscle mechanical properties could explain differences in balance performance. The mechanical properties included estimates of the maximal isometric force capability, force-length, force-velocity, and series elastic properties of the dorsiflexors and individual plantarflexor muscles (gastrocnemius and soleus). As expected, the older adults performed more poorly on most balance tasks. Muscular maximal isometric force, optimal fiber length, tendon slack length, and velocity-dependent force capabilities accounted for up to 60% of the age-related variation in performance on the static and dynamic balance tests. In general, the plantarflexors had a stronger predictive role than the dorsiflexors. Plantarflexor stiffness was strongly related to general balance performance, particularly in quiet stance; but this effect did not depend on age. Together, these results suggest that age-related differences in balance performance are explained in part by alterations in muscular mechanical properties.

The role of working memory, inhibition, and processing speed in text comprehension in children

The aim of the present study was to investigate age-related differences in text comprehension performance in 10- to 12-year-old children, analyzing the joint influence of working memory (WM), inhibition-related mechanisms, and processing speed. Children were administered: i) a text comprehension task in which the memory load was manipulated by allowing them to see the text while answering or withdrawing the text (text-present versus text-absent conditions); and ii) WM, inhibition and processing speed tasks. Results showed that age-related differences were not significant in the text-present condition, whereas older children performed better than younger ones in the text-absent condition. Regression analyses indicated that only WM accounted for a significant part of the variance in the text-present condition, whereas in the text-absent condition comprehension performance was explained by the combined contribution of WM and resistance to distractor interference. These findings confirm the crucial role of WM capacity in text processing and indicate that specific inhibitory mechanisms are involved in children's text processing when the comprehension task involves memory load.

Sex and age-related differences in performance in a 24-hour ultra-cycling draft-legal event - a cross-sectional data analysis.

BackgroundThe purpose of this study was to examine the sex and age-related differences in performance in a draft-legal ultra-cycling event.MethodsAge-related changes in performance across years were investigated in the 24-hour draft-legal cycling event held in Schötz, Switzerland, between 2000 and 2011 using multi-level regression analyses including age, repeated participation and environmental temperatures as co-variables.ResultsFor all finishers, the age of peak cycling performance decreased significantly (β = −0.273, p = 0.036) from 38 ± 10 to 35 ± 6 years in females but remained unchanged (β = −0.035, p = 0.906) at 41.0 ± 10.3 years in males. For the annual fastest females and males, the age of peak cycling performance remained unchanged at 37.3 ± 8.5 and 38.3 ± 5.4 years, respectively. For all female and male finishers, males improved significantly (β = 7.010, p = 0.006) the cycling distance from 497.8 ± 219.6 km to 546.7 ± 205.0 km whereas females (β = −0.085, p = 0.987) showed an unchanged performance of 593.7 ± 132.3 km. The mean cycling distance achieved by the male winners of 960.5 ± 51.9 km was significantly (p < 0.001) greater than the distance covered by the female winners with 769.7 ± 65.7 km but was not different between the sexes (p > 0.05). The sex difference in performance for the annual winners of 19.7 ± 7.8% remained unchanged across years (p > 0.05). The achieved cycling distance decreased in a curvilinear manner with advancing age. There was a significant age effect (F = 28.4, p < 0.0001) for cycling performance where the fastest cyclists were in age group 35–39 years.ConclusionIn this 24-h cycling draft-legal event, performance in females remained unchanged while their age of peak cycling performance decreased and performance in males improved while their age of peak cycling performance remained unchanged. The annual fastest females and males were 37.3 ± 8.5 and 38.3 ± 5.4 years old, respectively. The sex difference for the fastest finishers was ~20%. It seems that women were not able to profit from drafting to improve their ultra-cycling performance.

Neuroimaging explanations of age-related differences in task performance

Advancing age affects both cognitive performance and functional brain activity and interpretation of these effects has led to a variety of conceptual research models without always explicitly linking the two effects. However, to best understand the multifaceted effects of advancing age, age differences in functional brain activity need to be explicitly tied to the cognitive task performance. This work hypothesized that age-related differences in task performance are partially explained by age-related differences in functional brain activity and formally tested these causal relationships. Functional MRI data was from groups of young and old adults engaged in an executive task-switching experiment. Analyses were voxel-wise testing of moderated-mediation and simple mediation statistical path models to determine whether age group, brain activity and their interaction explained task performance in regions demonstrating an effect of age group. Results identified brain regions whose age-related differences in functional brain activity significantly explained age-related differences in task performance. In all identified locations, significant moderated-mediation relationships resulted from increasing brain activity predicting worse (slower) task performance in older but not younger adults. Findings suggest that advancing age links task performance to the level of brain activity. The overall message of this work is that in order to understand the role of functional brain activity on cognitive performance, analysis methods should respect theoretical relationships. Namely, that age affects brain activity and brain activity is related to task performance.

Does the greater involvement of executive control in memory with age act as a compensatory mechanism?

Recent behavioural and imaging data have shown that memory functioning seems to rely more on executive functions and on the prefrontal cortex (PFC) in older than in young adults. Using a behavioural approach, our objective was to confirm the hypothesis that young and older adults present different patterns of correlation between episodic memory performance and executive functioning. We report three studies comparing the correlations of young and older adults in a broad range of episodic memory and executive function tasks. The results indicated that memory and executive performance were consistently and significantly correlated in older but not in younger adults. Regression analyses confirmed that age-related differences in episodic memory performance could be explained by individual differences in executive functioning. The results are consistent with the view that memory functioning in aging is accompanied by a shift from automatic to controlled forms of processing. They also generalise the executive hypothesis of episodic memory aging and are in line with the idea that executive functions act as a compensatory mechanism against age-related memory decline.

Psychometric Properties and Reference Values for the ImPACT Neurocognitive Test Battery in a Sample of Elite Youth Ice Hockey Players

This cross-sectional study aimed to determine psychometric properties and reference values for ImPACT in a sample of 704 elite ice hockey players aged 13-17. Baseline ImPACT tests were completed at the beginning of the 2011-2012 season. Players aged 16-17 had better visual motor processing speed, adjusted R(2) = .0522, F(2, 45) = 10.79, β = 2.87, p < .001, and impulse control, adjusted R = .0185, F(2,45) = 7.46, β = -1.35, p = .001, than younger players, and girls had greater total symptom ratings than boys (z = -3.47, p = .0005). There were no other sex- or age-related differences in neurocognitive performance, and no effect of previous concussion on ImPACT scores. Reference values with cut-off scores are presented.