Age-related and Genetic Modulation of Frontal Cortex Efficiency

The dorsolateral pFC (DLPFC) is a key region for working memory. It has been proposed that the DLPFC is dynamically recruited depending on task demands. By this view, high DLPFC recruitment for low-demanding tasks along with weak DLPFC upregulation at higher task demands reflects low efficiency. Here, the fMRI BOLD signal during working memory maintenance and manipulation was examined in relation to aging and catechol-O-methyltransferase (COMT) Val158Met status in a large representative sample (n = 287). The efficiency hypothesis predicts a weaker DLPFC response during manipulation, along with a stronger response during maintenance for older adults and COMT Val carriers compared with younger adults and COMT Met carriers. Consistent with the hypothesis, younger adults and met carriers showed maximal DLPFC BOLD response during manipulation, whereas older adults and val carriers displayed elevated DLPFC responses during the less demanding maintenance condition. The observed inverted relations support a link between dopamine and DLPFC efficiency.

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Older adults benefit from more widespread brain network integration during working memory

10.1101/642447 ◽

2019 ◽

Cited By ~ 1

Author(s):

C.A. Crowell ◽

S.W. Davis ◽

L. Beynel ◽

L. Deng ◽

D. Lakhlani ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Network Connectivity ◽

Task Demands ◽

Global Network ◽

Aging Brain ◽

Network Integration ◽

Younger Adults ◽

Age Related ◽

Cortical Regions

AbstractNeuroimaging evidence suggests that the aging brain relies on a more distributed set of cortical regions than younger adults in order to maintain successful levels of performance during demanding cognitive tasks. However, it remains unclear how task demands give rise to this age-related expansion in cortical networks. To investigate this issue, we used functional magnetic resonance imaging to measure univariate activity, network connectivity, and cognitive performance in younger and older adults during a working memory (WM) task. In the WM task investigated, participants hold letters online (maintenance) while reordering them alphabetically (manipulation). WM load was titrated to obtain four individualized difficulty levels. Network integration—defined as the ratio of within-versus between-network connectivity—was linked to individual differences in WM capacity. The study yielded three main findings. First, as task difficulty increased, network integration decreased in younger adults, whereas it increased in older adults. Second, age-related increases in network integration were driven by increases in right hemispheric connectivity to both left and right cortical regions, a finding that helps to reconcile extant theories of compensatory recruitment in aging to address the multivariate dynamics of global network functioning. Lastly, older adults with higher WM capacity demonstrated higher levels of network integration in the most difficult condition. These results shed light on the mechanisms of age-related network reorganization by suggesting that changes in network connectivity may act as an adaptive form of compensation, with older adults recruiting a more distributed cortical network as task demands increase.Significance statementOlder adults often activate brain regions not engaged by younger adults, but the circumstances under which this widespread network emerges are unclear. Here, we examined the effects of aging on network connectivity between task regions recruited during a working memory (WM) manipulation task, and the rest of the brain. We found an age-related increase in the more global network integration in older adults, and an association between this integration and working memory capacity in older adults. The findings are generally consistent with the compensatory interpretation of these effects.

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Resolving Age-Related Differences in Working Memory: Equating Perception and Attention Makes Older Adults Remember as Well as Younger Adults

Experimental Aging Research ◽

10.1080/0361073x.2019.1586120 ◽

2019 ◽

Vol 45 (2) ◽

pp. 120-134 ◽

Cited By ~ 4

Author(s):

Paul Verhaeghen ◽

Shriradha Geigerman ◽

Haoxiang Yang ◽

Alejandra C. Montoya ◽

Dobromir Rahnev

Keyword(s):

Older Adults ◽

Working Memory ◽

Younger Adults ◽

Age Related

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What affects the magnitude of age-related dual-task costs in working memory? The role of stimulus domain and access to semantic representations

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021820970744 ◽

2020 ◽

pp. 174702182097074

Author(s):

Agnieszka J Jaroslawska ◽

Stephen Rhodes ◽

Clément Belletier ◽

Jason M Doherty ◽

Nelson Cowan ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Dual Task ◽

Memory Task ◽

Semantic Representations ◽

Younger Adults ◽

Task Effects ◽

Concurrent Processing ◽

Age Related

Although there is evidence that the effect of including a concurrent processing demand on the storage of information in working memory is disproportionately larger for older than younger adults, not all studies show this age-related impairment, and the critical factors responsible for any such impairment remain elusive. Here we assess whether domain overlap between storage and processing activities, and access to semantic representations, are important determinants of performance in a sample of younger and older adults ( N = 119). We developed four versions of a processing task by manipulating the type of stimuli involved (either verbal or non-verbal) and the decision that participants had to make about the stimuli presented on the screen. Participants either had to perform a spatial judgement, in deciding whether the verbal or non-verbal item was presented above or below the centre of the screen, or a semantic judgement, in deciding whether the stimulus refers to something living or not living. The memory task was serial-ordered recall of visually presented letters. The study revealed a large increase in age-related memory differences when concurrent processing was required. These differences were smaller when storage and processing activities both used verbal materials. Dual-task effects on processing were also disproportionate for older adults. Age differences in processing performance appeared larger for tasks requiring spatial decisions rather than semantic decisions. We discuss these findings in relation to three competing frameworks of working memory and the extant literature on cognitive ageing.

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Working Memory Training From an Individual Differences Perspective

Cognitive and Working Memory Training ◽

10.1093/oso/9780199974467.003.0002 ◽

2019 ◽

pp. 14-39

Author(s):

Erika Borella ◽

Barbara Carretti ◽

Cesare Cornoldi ◽

Rossana De Beni

Keyword(s):

Older Adults ◽

Working Memory ◽

Task Demands ◽

Memory Training ◽

Training Procedure ◽

Adaptive Procedure ◽

Age Related ◽

Short And Long Term ◽

Underlying Processes

This chapter presents and discusses a verbal WM training developed for older adults. The model of working memory (WM) proposed by Cornoldi and Vecchi, which is based on an analysis of individual and age-related differences, is used as a framework for discussing the efficacy of the WM training procedure proposed and developed for older adults. The model (a) assumes that different WM tasks (and underlying processes) may be located along two continua that describe the type of content to be processed and the degree of active control required by the task and (b) considers metacognitive/motivational aspects, which also have a role in determining WM performance. The WM training procedure presented here takes into account not only the capacity to use WM resources and attentional control by adopting an adaptive procedure, but also the importance of including variations in the training task demands to produce a challenging and engaging task that sustains motivation and favor the training’s short- and long-term efficacy, at least in older adults. These aspects seem crucial in explaining the results obtained with this verbal WM training program in aging.

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Catechol-O-methyltransferase (COMT) Genotype Affects Age-Related Changes in Plasticity in Working Memory: A Pilot Study

BioMed Research International ◽

10.1155/2014/414351 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 11

Author(s):

Stephan Heinzel ◽

Thomas G. Riemer ◽

Stefanie Schulte ◽

Johanna Onken ◽

Andreas Heinz ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Genetic Variation ◽

Behavioral Plasticity ◽

Memory Performance ◽

Dopamine Metabolism ◽

Comt Genotype ◽

Younger Adults ◽

Age Related ◽

Age Related Changes

Objectives. Recent work suggests that a genetic variation associated with increased dopamine metabolism in the prefrontal cortex (catechol-O-methyltransferase Val158Met; COMT) amplifies age-related changes in working memory performance. Research on younger adults indicates that the influence of dopamine-related genetic polymorphisms on working memory performance increases when testing the cognitive limits through training. To date, this has not been studied in older adults.Method. Here we investigate the effect of COMT genotype on plasticity in working memory in a sample of 14 younger (aged 24–30 years) and 25 older (aged 60–75 years) healthy adults. Participants underwent adaptive training in then-back working memory task over 12 sessions under increasing difficulty conditions.Results. Both younger and older adults exhibited sizeable behavioral plasticity through training (P<.001), which was larger in younger as compared to older adults (P<.001). Age-related differences were qualified by an interaction with COMT genotype (P<.001), and this interaction was due to decreased behavioral plasticity in older adults carrying the Val/Val genotype, while there was no effect of genotype in younger adults.Discussion. Our findings indicate that age-related changes in plasticity in working memory are critically affected by genetic variation in prefrontal dopamine metabolism.

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Measuring the subjective cost of listening effort using a discounting task

10.31234/osf.io/zc9jg ◽

2020 ◽

Author(s):

Drew Jordan McLaughlin ◽

Todd Samuel Braver ◽

Jonathan E. Peelle

Keyword(s):

Older Adults ◽

Decision Making ◽

Working Memory ◽

Economic Status ◽

Monetary Reward ◽

Future Research ◽

Listening Effort ◽

Younger Adults ◽

Age Related ◽

Economic Decision Making

Purpose: Objective measures of listening effort have been gaining prominence, as they provide metrics to quantify the difficulty of understanding speech under a variety of circumstances. A key challenge has been to develop paradigms that enable the complementary measurement of subjective listening effort in a quantitatively precise manner. In the present study, we introduce a novel decision-making paradigm to examine age-related and individual differences in subjective effort during listening.Method: Older and younger adults were presented with spoken sentences mixed with speech-shaped noise at multiple signal-to-noise ratios (SNRs). On each trial subjects were offered the choice between completing an easier listening trial (presented at +20 dB SNR) for a smaller monetary reward, or a harder listening trial (presented at either +4, 0, -4, -8, or -12 dB SNR) for a greater monetary reward. By varying the amount of the reward offered for the easier option, the subjective value of performing effortful listening trials at each SNR could be assessed. Results: Older adults discounted the value of effortful listening to a greater degree than young adults, opting to accept less money in order to avoid more difficult SNRs. Additionally, older adults with poorer hearing and smaller working memory capacities were more likely to choose easier trials; however, in younger adults, no relationship with hearing or working memory was found. Self-reported measures of economic status did not affect these relationships. Conclusion: These findings suggest that subjective listening effort depends on factors including, but not necessarily limited to, hearing and working memory. Additionally, this study demonstrates that economic decision-making paradigms can be a useful approach for assessing subjective listening effort, and may prove beneficial in future research.

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Strategic prioritisation enhances young and older adults’ visual feature binding in working memory

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021820960712 ◽

2020 ◽

pp. 174702182096071

Author(s):

Richard J Allen ◽

Amy L Atkinson ◽

Louise A Brown Nicholls

Keyword(s):

Older Adults ◽

Working Memory ◽

Serial Position ◽

Visual Working Memory ◽

Memory Performance ◽

Feature Binding ◽

Younger Adults ◽

Age Related ◽

Presentation Time ◽

Benefits And Costs

Visual working memory for features and bindings is susceptible to age-related decline. Two experiments were used to examine whether older adults are able to strategically prioritise more valuable information in working memory and whether this could reduce age-related impairments. Younger (18–33 years) and older (60–90 years) adults were presented with coloured shapes and, following a brief delay, asked to recall the feature that had accompanied the probe item. In Experiment 1, participants were either asked to prioritise a more valuable object in the array (serial position 1, 2, or 3) or to treat them all equally. Older adults exhibited worse overall memory performance but were as able as younger adults to prioritise objects. In both groups, this ability was particularly apparent at the middle serial position. Experiment 2 then explored whether younger and older adults’ prioritisation is affected by presentation time. Replicating Experiment 1, older adults were able to prioritise the more valuable object in working memory, showing equivalent benefits and costs as younger adults. However, processing speed, as indexed by presentation time, was shown not to limit strategic prioritisation in either age group. Taken together, these findings demonstrate that, although older adults have poorer visual working memory overall, the ability to strategically direct attention to more valuable items in working memory is preserved across ageing.

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Age-related effects on a novel dual-task Stroop paradigm

PLoS ONE ◽

10.1371/journal.pone.0247923 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0247923

Author(s):

Nathan Ward ◽

Erika Hussey ◽

Reem Alzahabi ◽

John G. Gaspar ◽

Arthur F. Kramer

Keyword(s):

Older Adults ◽

Trial Type ◽

Dual Task ◽

Secondary Task ◽

Task Type ◽

Task Demands ◽

Younger Adults ◽

Age Related ◽

Type Interaction ◽

Font Color

The Stroop task is a traditional measure of cognitive control processes, yet results remain mixed when it comes to assessing age-related differences perhaps in part due to strategies participants use to reduce inhibitory control demands required for success on the task. Thirty-three older adults and 34 younger adults completed a Baseline (traditional, single-task) version of Stroop, followed by two, novel dual-task Stroop variants: Color-Dual (maintain secondary count of prespecified font color regardless the lexical content) and Lexical-Dual (maintain secondary count of prespecified word regardless the font color). With regard to Baseline performance, we predicted an Age x Trial Type interaction in which older adults would be selectively impaired on Incongruent trials compared to younger adults, and this prediction was supported. When we added secondary task demands, we predicted a Trial Type x Dual-Task Type interaction in which performance in the Lexical-Dual condition would be worse than performance in the Color-Dual condition. This prediction was also supported, suggesting that having a secondary task that activated the irrelevant stream of information required more inhibitory control. Finally, we also predicted that Age would interact with Trial Type and Dual-Task Type, which was partially supported in response latencies and more definitively supported in error rates. Overall, our results indicate that Stroop performance is differentially influenced by additional dual-task demands that potentially minimize strategy usage, which has implications for both young and older adult Stroop performance.

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Age Effects on Adjustments of Performance Monitoring to Task Difficulty

Journal of Psychophysiology ◽

10.1027/0269-8803/a000077 ◽

2012 ◽

Vol 26 (4) ◽

pp. 145-153 ◽

Cited By ~ 10

Author(s):

Melanie Schreiber ◽

Tanja Endrass ◽

Anne Weigand ◽

Norbert Kathmann

Keyword(s):

Older Adults ◽

Task Difficulty ◽

Performance Monitoring ◽

Age Groups ◽

Task Demands ◽

Response Strategy ◽

Younger Adults ◽

Age Related ◽

Difficult Condition ◽

Visual Size

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.

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Age Differences in Memory-Based Task Switching With and Without Cues

Journal of Psychophysiology ◽

10.1027/0269-8803/a000125 ◽

2014 ◽

Vol 28 (3) ◽

pp. 187-201 ◽

Cited By ~ 29

Author(s):

Sergei A. Schapkin ◽

Patrick D. Gajewski ◽

Gabriele Freude

Keyword(s):

Older Adults ◽

Working Memory ◽

Age Differences ◽

Task Switching ◽

Response Selection ◽

Younger Adults ◽

Switch Costs ◽

Age Related ◽

Mixing Costs ◽

And Task

The study investigated the neuronal mechanisms of age-related changes in mixing costs during memory-based task switching with two levels of working memory (WM) load. Forty-eight healthy younger and 45 healthy older participants performed a memory based (high WM load) and a memory plus cue based (low WM load) switching task while event-related brain potentials (ERPs) were registered. Older adults revealed larger mixing costs in both reaction time (RT) and accuracy at higher WM loads than younger adults. The presence of explicit cues substantially reduced age differences in mixing costs for accuracy but not for RT. Similarly, no age differences regarding local switch costs were found at lower WM load. Surprisingly, larger RT local costs in younger adults than in older adults were found in the memory-based block. The CNV was reduced under high WM load and positively correlated with accuracy mixing costs in older adults. The target-locked occipital N1 and fronto-central P2 were larger in older adults relative to younger adults irrespective of WM load. The P2 latency reflected the pattern of switch costs observed in behavioral data. Moreover, P2 latency positively correlated with RT mixing costs in older adults. Elderly also showed a delayed N2 and a delayed and reduced P3b. The results suggest that age-related differences in mixing costs may be partially due to a less efficient task preparation and task set maintenance (CNV) in elderly. However, elderly attempted to compensate for these deficits by permanent activation of mechanisms relating to stimulus encoding (N1) and task-set retrieval (P2). Finally, the delayed fronto-central N2 as well as the delayed and reduced parietal P3b strongly suggest delays of response selection and working memory updating in elderly due to an increase in selection threshold or in response selection variability constituting the performance decline.

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