scholarly journals Age-related differences in visual encoding and response strategies contribute to spatial memory deficits

2020 ◽  
Author(s):  
Vladislava Segen ◽  
Marios N Avraamides ◽  
Timothy J. Slattery ◽  
Jan Wiener

Successful navigation requires the ability to memorise and recognise the locations of objects across different perspectives. Although these abilities rely on hippocampal functioning that is susceptible to degeneration in older adults, little is known about the effects of ageing on encoding and response strategies that are used to recognise spatial configurations. To investigate this, we asked young and older participants to encode the locations of objects in a virtual room shown as a picture on a computer screen. Then, we asked participants to view a second picture of the same room taken from the same (0°) or a different perspective (45° or 135°), and judge whether the objects occupied the same or different locations. Results revealed that older adults had overall greater difficulty with the task than younger adults and that the introduction of perspective shift between encoding and testing impaired performance in both age groups. With diffusion modelling we also found that older adults adopted a more conservative response strategy while the analysis of gaze patterns revealed an age-related shift in visual encoding strategies with older adults attending to more information when memorising the positions of objects in space.

2020 ◽  
Author(s):  
Vladislava Segen ◽  
Marios N Avraamides ◽  
Timothy J. Slattery ◽  
Jan Wiener

Ageing is associated with declines in spatial memory, however, the source of these deficits remains unclear. Here we used eye-tracking to investigate age-related differences in spatial encoding strategies and the cognitive processes underlying the age-related deficits in spatial memory tasks. To do so we asked young and older participants to encode the locations of objects in a virtual room shown as a picture on a computer screen. The availability and utility of room-based landmarks was manipulated by removing landmarks, presenting identical landmarks rendering them uninformative, or by presenting unique landmarks that could be used to encode object locations. In the test phase, participants viewed a second picture of the same room taken from the same (0°) or a different perspective (30°) and judged whether the objects occupied the same or different locations in the room. We found that the introduction of perspective shift and swapping of objects between encoding and testing impaired performance in both age groups. Furthermore, our results revealed that although older adults performed the task as well as younger participants, they relied on different visual encoding strategies to solve the task. Specifically, gaze analysis revealed that older adults showed a greater preference towards a more categorical encoding strategy in which they formed relationships between objects and landmarks.


Author(s):  
Vladislava Segen ◽  
Marios N. Avraamides ◽  
Timothy J. Slattery ◽  
Jan M. Wiener

AbstractAgeing is associated with declines in spatial memory, however, the source of these deficits remains unclear. Here we used eye-tracking to investigate age-related differences in spatial encoding strategies and the cognitive processes underlying the age-related deficits in spatial memory tasks. To do so we asked young and older participants to encode the locations of objects in a virtual room shown as a picture on a computer screen. The availability and utility of room-based landmarks were manipulated by removing landmarks, presenting identical landmarks rendering them uninformative, or by presenting unique landmarks that could be used to encode object locations. In the test phase, participants viewed a second picture of the same room taken from the same (0°) or a different perspective (30°) and judged whether the objects occupied the same or different locations in the room. We found that the introduction of a perspective shift and swapping of objects between encoding and testing impaired performance in both age groups. Furthermore, our results revealed that although older adults performed the task as well as younger participants, they relied on different visual encoding strategies to solve the task. Specifically, gaze analysis revealed that older adults showed a greater preference towards a more categorical encoding strategy in which they formed relationships between objects and landmarks.


2012 ◽  
Vol 26 (4) ◽  
pp. 145-153 ◽  
Author(s):  
Melanie Schreiber ◽  
Tanja Endrass ◽  
Anne Weigand ◽  
Norbert Kathmann

Performance monitoring which is a core component of the executive functions has been found to be altered in older adults. Specifically, older adults showed smaller amplitudes of the error-related negativity (Ne/ERN) but increased amplitudes of the correct-related negativity (Nc/CRN), and a lack of adjustment to stimulus-response compatibility. The present study used a visual size discrimination task with two difficulty levels to further examine age-related alterations of the adaptation to actual task demands. Older adults showed a cautious response strategy with slower but more accurate responses than younger adults. Both age groups showed post-error slowing. Misperception of errors in the difficult condition was larger in older adults. In contrast to older adults, Ne/ERN amplitudes decreased and Nc/CRN amplitudes increased from the easy to the difficult condition in younger adults. This may indicate that adjustment to task difficulty was reduced in the older age group. It is concluded that conscious perception of errors and adaptation of the automatic performance monitoring to changing task demands are affected by age.


2014 ◽  
Vol 30 (4) ◽  
pp. 542-546 ◽  
Author(s):  
Dennis E. Anderson ◽  
Christopher T. Franck ◽  
Michael L. Madigan

The effects of gait speed and step length on the required coefficient of friction (COF) confound the investigation of age-related differences in required COF. The goals of this study were to investigate whether age differences in required COF during self-selected gait persist when experimentally-controlling speed and step length, and to determine the independent effects of speed and step length on required COF. Ten young and 10 older healthy adults performed gait trials under five gait conditions: self-selected, slow and fast speeds without controlling step length, and slow and fast speeds while controlling step length. During self-selected gait, older adults walked with shorter step lengths and exhibited a lower required COF. Older adults also exhibited a lower required COF when walking at a controlled speed without controlling step length. When both age groups walked with the same speed and step length, no age difference in required COF was found. Thus, speed and step length can have a large influence on studies investigating age-related differences in required COF. It was also found that speed and step length have independent and opposite effects on required COF, with step length having a strong positive effect on required COF, and speed having a weaker negative effect.


Author(s):  
Lauren Werner ◽  
Gaojian Huang ◽  
Brandon J. Pitts

The number of older adults is growing significantly worldwide. At the same time, technological developments are rapidly evolving, and older populations are expected to interact more frequently with such sophisticated systems. Automated speech recognition (ASR) systems is an example of one technology that is increasingly present in daily life. However, age-related physical changes may alter speech production and limit the effectiveness of ASR systems for older individuals. The goal of this paper was to summarize the current knowledge on ASR systems and older adults. The PRISMA method was employed and 17 studies were compared on the basis of word error rate (WER). Overall, WER was found to be influenced by age, gender, and the number of speech samples used to train ASR systems. This work has implications for the development of future human-machine technologies that will be used by a wide range of age groups.


Author(s):  
Hyun Gu Kang ◽  
Jonathan B. Dingwell

Older adults commonly walk slower, which many believe helps improve their walking stability. However, they remain at increased risk of falls. We investigated how differences in age and walking speed independently affect dynamic stability during walking, and how age-related changes in leg strength and ROM affected this relationship. Eighteen active healthy older and 17 younger adults walked on a treadmill for 5 minutes each at each of 5 speeds (80–120% of preferred). Local divergence exponents and maximum Floquet multipliers (FM) were calculated to quantify each subject’s responses to small inherent perturbations during walking. These older adults exhibited the same preferred walking speeds as the younger subjects (p = 0.860). However, these older adults still exhibited greater local divergence exponents (p<0.0001) and higher maximum FM (p<0.007) than young adults at all walking speeds. These older adults remained more unstable (p<0.04) even after adjusting for declines in both strength and ROM. In both age groups, local divergence exponents decreased at slower speeds and increased at faster speeds (p<0.0001). Maximum FM showed similar changes with speed (p<0.02). The older adults in this study were healthy enough to walk at normal speeds. However, these adults were still more unstable than the young adults, independent of walking speed. This greater instability was not explained by loss of leg strength and ROM. Slower speeds led to decreased instability in both groups.


2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S841-S842
Author(s):  
Madeline J Nichols ◽  
Jennifer A Bellingtier ◽  
Frances Buttelmann

Abstract Every day we use emotion words to describe our experiences, but past research finds that the meanings of these words can vary. Furthermore, historical shifts in language use and experiential knowledge of the emotions may contribute to age-differences in what these emotion words convey. We examined age-related differences in the valence, arousal, and expression connoted by the words anger, love, and sadness. We predicted age-related differences in the semantic meanings of the words would emerge such that older adults would more clearly differentiate the positivity/negativity of the words, whereas younger adults would report higher endorsement for the conveyed arousal and expression. Participants included American and German older adults (N=61; mean age=68.98) and younger adults (N=77; mean age=20.77). Using the GRID instrument (Swiss Center for Affective Sciences, 2013), they rated each emotion word for its valence, arousal, and expression when used by a speaker of the participant’s native language. Across emotions and dimensions, older adults were generally more moderate in their understanding of emotion words. For example, German older adults rated anger and sadness as suggesting the speaker felt less bad and more good than the younger adults. American older adults rated love as connoting the speaker felt more bad and less good than younger adults. Arousal ratings were higher for German younger, as opposed to older, adults. Cultural differences were most pronounced for sadness such that German participants gave more moderate answers than American participants. Overall, our research suggests that there are age-related differences in the understanding of emotion words.


BMJ Open ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. e027728 ◽  
Author(s):  
Siobhan Leahy ◽  
Marica Cassarino ◽  
Matthew DL O' Connell ◽  
Liam Glynn ◽  
Rose Galvin

IntroductionTwo major global health challenges are the rapidly ageing population and the high prevalence of obesity in all age groups. Older adults are also susceptible to age-related loss of muscle strength, termed dynapaenia. The co-occurrence of both obesity and dynapaenia, termed dynapaenic obesity (DO), has been associated with poorer health outcomes and increased healthcare usage compared with either state alone. The purpose of this systematic review is to quantify the prevalence and incidence of DO in older adult populations, and to explore the association between DO and health outcomes, specifically chronic disease and multimorbidity, functional disability and healthcare usage.Methods and analysisUsing the Meta-analyses Of Observational Studies in Epidemiology guidelines, we will conduct a systematic review of cross-sectional and longitudinal observational studies of older adults, which include measures of DO and specified outcomes. Detailed literature searches of will be conducted using six electronic databases: Excerpta Medica dataBASE (EMBASE), PubMed, MEDLINE, SCOPUS, ScienceDirect and Cumulative Index of Nursing and Allied Health Complete (CINAHL), including articles published from database inception until Febuary 2019. The reference lists of included articles will also be searched. Two independent reviewers will undertake a three-step screening and review process using the Population, Risk Factor, Outcome framework to define eligibility. The Newcastle Ottawa Scale for non-randomised studies will be used to assess risk of bias and to rate study quality. The findings will be synthesised in a narrative summary, and a meta-analysis will be conducted where appropriate.Ethics and disseminationEthical approval is not required for this systematic review. Findings from this research will be submitted for peer-reviewed publication in academic journals, and presented at relevant academic conferences.PROSPERO registration numberCRD42018112471.


Author(s):  
Holly E. Hancock ◽  
Arthur D. Fisk ◽  
Wendy A. Rogers

Successful comprehension of warning text necessitates an ability to understand both explicitly stated safety information, as well as information about hazards and safe product usage that may be implied. Comprehension level for this type of text may vary across age groups as a function of normal age-related changes that may be experienced in memory and text comprehension in general. To date, there has been no comprehensive investigation of how well younger and older adults understand explicit and implicit information associated with actual product warnings. In the current study, 43 older and 42 younger adults read text from consumer product warnings and then rated the truth/falsity of statements containing information that was either explicitly stated or implied by the warnings. The results suggest both older and younger adults are able to recognize information that is explicitly associated with an actual product warning. However, they are less able to recognize information that can be inferred from warnings. These data also suggest that older adults perceive themselves to understand consumer warnings fairly well.


2003 ◽  
Vol 88 (1) ◽  
pp. 185-191 ◽  
Author(s):  
Reinhold Vieth ◽  
Yasmin Ladak ◽  
Paul G. Walfish

Vitamin D requirements are thought to vary with age, but there is little comparative evidence for this. One goal in establishing a vitamin D requirement is to avoid secondary hyperparathyroidism. We studied 1741 euthyroid, thyroid clinic outpatients without evidence of calcium abnormalities, ranging in age from 19 to 97 yr, whose serum and urine had been analyzed for calcium, vitamin D, and parathyroid status. We found no effect of age on the 25-hydroxyvitamin D [25(OH)D] concentration associated with specific vitamin D intakes, and there was no relationship between 25(OH)D and 1,25hydroxyvitamin D [1,25(OH)2D]. In every age group, serum 1,25(OH)2D declined with increasing creatinine (P < 0.001). What changed with age included creatinine, which correlated with 25(OH)D (r = 0.146, P < 0.001) only in the youngest age group (19–50 yr) but not in the older age groups (P > 0.1). Creatinine did not correlate with PTH in the youngest age group, but the relationship became significant as age increased (e.g. for the elderly, r = 0.365, P < 0.001). Linear regression of log PTH vs. log 25(OH)D agreed with the natural shape of the relationship observed with scatterplot smoothing, and this showed no plateau in PTH as 25(OH)D increased. We compared PTH concentrations among age groups, based on 20 nmol/liter increments in 25(OH)D. Mean PTH in adults older than 70 yr was consistently higher than in adults younger than 50 yr (P < 0.05 by ANOVA and Dunnett’s t test). PTH levels of the elderly who had 25(OH)D concentrations greater than 100 nmol/liter matched PTH of younger adults having 25(OH)D concentrations near 70 nmol/liter. This study shows that all age groups exhibit a high prevalence of 25(OH)D insufficiency and secondary hyperparathyroidism. Older adults are just as efficient in maintaining 25(OH)D, but they need more vitamin D to produce the higher 25(OH)D concentrations required to overcome the hyperparathyroidism associated with their diminishing renal function.


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