scholarly journals Task-induced functional brain connectivity mediates the relationship between striatal D2/3 receptors and working memory

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Matthew M Nour ◽  
Tarik Dahoun ◽  
Robert A McCutcheon ◽  
Rick A Adams ◽  
Matthew B Wall ◽  
...  
Keyword(s):  
Working Memory ◽  
Functional Connectivity ◽  
Task Performance ◽  
Memory Load ◽  
Brain Connectivity ◽  
Memory Performance ◽  
Age Related ◽  
Positron Emission ◽  
The Relationship ◽  
And Task

Working memory performance is thought to depend on both striatal dopamine 2/3 receptors (D2/3Rs) and task-induced functional organisation in key cortical brain networks. Here, we combine functional magnetic resonance imaging and D2/3R positron emission tomography in 51 healthy volunteers, to investigate the relationship between working memory performance, task-induced default mode network (DMN) functional connectivity changes, and striatal D2/3R availability. Increasing working memory load was associated with reduced DMN functional connectivity, which was itself associated with poorer task performance. Crucially, the magnitude of the DMN connectivity reduction correlated with striatal D2/3R availability, particularly in the caudate, and this relationship mediated the relationship between striatal D2/3R availability and task performance. These results inform our understanding of natural variation in working memory performance, and have implications for understanding age-related cognitive decline and cognitive impairments in neuropsychiatric disorders where dopamine signalling is altered.

scholarly journals Alpha Phase Dynamics Predict Age-Related Visual Working Memory Decline

2016 ◽  
Author(s):  
Tam T. Tran ◽  
Nicole C. Hoffner ◽  
Sara C. LaHue ◽  
Lisa Tseng ◽  
Bradley Voytek
Keyword(s):  
Older Adults ◽  
Working Memory ◽  
Response Time ◽  
Healthy Aging ◽  
Memory Load ◽  
Memory Performance ◽  
Alpha Phase ◽  
Phase Dynamics ◽  
Memory Array ◽  
Age Related

AbstractAlpha oscillations are modulated in response to visual temporal and spatial cues, However, the neural response to alerting cues is less explored, as is how this response is affected by healthy aging. Using scalp EEG, we examined how visual cortical alpha activity relates to working memory performance. Younger (20-30 years) and older (60-70 years) participants were presented with a visual alerting cue uninformative of the position or size of a lateralized working memory array. Older adults showed longer response times overall, and reduced accuracy when memory load was high. Older adults had less consistent cue-evoked phase resetting than younger adults, which predicted worse performance. Alpha phase prior to memory array presentation predicted response time, but the relationship between phase and response time was weaker in older adults. These results suggest that changes in alpha phase dynamics, especially prior to presentation of task-relevant stimuli, potentially contribute to age-related cognitive decline.

scholarly journals Relationship between Memory Load and Listening Demands in Age-Related Hearing Impairment

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Julia Pauquet ◽  
Christiane M. Thiel ◽  
Christian Mathys ◽  
Stephanie Rosemann
Keyword(s):  
Working Memory ◽  
Hearing Loss ◽  
Task Performance ◽  
Memory Load ◽  
Memory Task ◽  
Listening Condition ◽  
Behavioral Level ◽  
Age Related ◽  
Bold Responses ◽  
Age Related Hearing Loss

Age-related hearing loss has been associated with increased recruitment of frontal brain areas during speech perception to compensate for the decline in auditory input. This additional recruitment may bind resources otherwise needed for understanding speech. However, it is unknown how increased demands on listening interact with increasing cognitive demands when processing speech in age-related hearing loss. The current study used a full-sentence working memory task manipulating demands on working memory and listening and studied untreated mild to moderate hard of hearing ( n = 20 ) and normal-hearing age-matched participants ( n = 19 ) with functional MRI. On the behavioral level, we found a significant interaction of memory load and listening condition; this was, however, similar for both groups. Under low, but not high memory load, listening condition significantly influenced task performance. Similarly, under easy but not difficult listening conditions, memory load had a significant effect on task performance. On the neural level, as measured by the BOLD response, we found increased responses under high compared to low memory load conditions in the left supramarginal gyrus, left middle frontal gyrus, and left supplementary motor cortex regardless of hearing ability. Furthermore, we found increased responses in the bilateral superior temporal gyri under easy compared to difficult listening conditions. We found no group differences nor interactions of group with memory load or listening condition. This suggests that memory load and listening condition interacted on a behavioral level, however, only the increased memory load was reflected in increased BOLD responses in frontal and parietal brain regions. Hence, when evaluating listening abilities in elderly participants, memory load should be considered as it might interfere with the assessed performance. We could not find any further evidence that BOLD responses for the different memory and listening conditions are affected by mild to moderate age-related hearing loss.

scholarly journals Functional connectivity between task-positive and task-negative brain areas and its relation to working memory performance

2010 ◽  
Vol 28 (8) ◽  
pp. 1051-1057 ◽  
Author(s):  
Michelle Hampson ◽  
Naomi Driesen ◽  
Jennifer K. Roth ◽  
John C. Gore ◽  
R. Todd Constable
Keyword(s):  
Working Memory ◽  
Functional Connectivity ◽  
Memory Performance ◽  
Brain Areas ◽  
And Task

scholarly journals Cooperative Contributions of Structural and Functional Connectivity to Successful Memory and Aging

2017 ◽  
Author(s):  
Simon W Davis ◽  
Amanda Szymanski ◽  
Homa Boms ◽  
Thomas Fink ◽  
Roberto Cabeza
Keyword(s):  
Functional Connectivity ◽  
Associative Memory ◽  
Latent Variables ◽  
Memory Performance ◽  
Structural Connectivity ◽  
Equation Modeling ◽  
Cognitive Changes ◽  
Age Related ◽  
The Relationship ◽  
Age Related Changes

AbstractUnderstanding the precise relation between functional connectivity and structural (white-matter) connectivity and how these relationships account for cognitive changes in older adults are major challenges for neuroscience. We investigate these issues using a new approach in which structural equation modeling (SEM) is employed to integrate functional and structural connectivity data analyzed with a common framework based on regions connected by canonical tract groups (CTGs). CTGs (e.g., uncinate fasciculus, cingulum, etc.) serve as a common currency between functional and structural connectivity matrices, and ensures that the same amount of data contributing to brain-behavior relationships. We used this approach to investigate the neural mechanisms supporting memory for items and memory for associations, and how they are affected by healthy aging. Our results are threefold. Firstly, structural and functional CTGs made independent contributions to associative memory performance, suggesting that both forms of connectivity underlie age-related changes in associative memory. Secondly, distinct groups of CTGs supported associative versus item memory. Lastly, the relationship between functional and structural connectivity was best explained by the relationship between latent variables describing functional and structural CTGs based on a constrained set of tracts—but no one specific CTG group—suggesting that age effects in connectivity are constrained to specific pathways. These results provide further insights into the interplay between structural and functional connectivity patterns, and help to elucidate their relative contribution to age-related changes in associative memory performance.

scholarly journals Neural Representation of Auditory Speech Processing in Age-Related Hearing Impairment

2020 ◽  
Author(s):  
Julia Pauquet ◽  
Christiane Thiel ◽  
Christian Mathys ◽  
Stephanie Rosemann
Keyword(s):  
Working Memory ◽  
Hearing Loss ◽  
Task Performance ◽  
Speech Processing ◽  
Memory Load ◽  
Listening Condition ◽  
Auditory Speech ◽  
Behavioral Level ◽  
Age Related ◽  
Age Related Hearing Loss

Age-related hearing loss has been associated with increased recruitment of frontal brain areas during speech perception to compensate for the decline in auditory input. This additional recruitment may bind resources otherwise needed for understanding speech. However, it is unknown how increased demands on listening interact with increasing cognitive demands when processing speech in age-related hearing loss. The current study used a full-sentence working memory task manipulating demands on working memory and listening and studied untreated mild to moderate hard of hearing (n = 20) and normal-hearing age-matched participants (n = 19) with functional MRI. On the behavioral level, we found a significant interaction of memory load and listening condition; this was, however, similar for both groups. Under low, but not high memory load, listening condition significantly influenced task performance. Similarly, under easy but not difficult listening conditions, memory load had a significant effect on task performance. On the neural level, we found increased responses under high compared to low memory load conditions in the left supramarginal gyrus, left middle frontal gyrus and left supplementary motor cortex regardless of hearing ability. Furthermore, we found increased responses in the bilateral superior temporal gyri under easy compared to difficult listening conditions. We found no group differences nor interactions of groups with memory load or listening conditions. This suggests that memory load and listening conditions interacted on a behavioral level, however, only the increased memory load was reflected in increased neural responses in frontal and parietal brain regions. Hence, when evaluating listening abilities in elderly participants, memory load should be considered as it might interfere with the assessed performance. We could not find any further evidence that neural mechanisms of auditory speech processing are affected by mild to moderate age-related hearing loss.

scholarly journals Spectral slowing is associated with working memory performance in children born very preterm

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Julie Sato ◽  
Sarah I. Mossad ◽  
Simeon M. Wong ◽  
Benjamin A. E. Hunt ◽  
Benjamin T. Dunkley ◽  
...  
Keyword(s):  
Working Memory ◽  
Task Performance ◽  
Visual Information ◽  
Brain Connectivity ◽  
Memory Performance ◽  
Alpha Band ◽  
Theta Band ◽  
Whole Brain ◽  
Very Preterm ◽  
Oscillatory Mechanisms

Abstract Children born very preterm (VPT) often demonstrate selective difficulties in working memory (WM), which may underlie academic difficulties observed in this population. Despite this, few studies have investigated the functional networks underlying WM in young children born VPT, a period when cognitive deficits become apparent. Using magnetoencephalography, we examined the networks underlying the maintenance of visual information in 6-year-old VPT (n = 15) and full-term (FT; n = 20) children. Although task performance was similar, VPT children engaged different oscillatory mechanisms during WM maintenance. Within the FT group, we observed higher mean whole-brain connectivity in the alpha-band during the retention (i.e. maintenance) interval associated with correct compared to incorrect responses. VPT children showed reduced whole-brain alpha synchrony, and a different network organization with fewer connections. In the theta-band, VPT children demonstrated a slight increase in whole-brain connectivity during WM maintenance, and engaged similar network hubs as FT children in the alpha-band, including the left dorsolateral prefrontal cortex and superior temporal gyrus. These findings suggest that VPT children rely on the theta-band to support similar task performance. Altered oscillatory mechanisms may reflect a less mature pattern of functional recruitment underlying WM in VPT children, which may affect the processing in complex ecological situations.

scholarly journals Cooperative contributions of structural and functional connectivity to successful memory in aging

2019 ◽  
Vol 3 (1) ◽  
pp. 173-194 ◽  
Author(s):  
Simon W. Davis ◽  
Amanda Szymanski ◽  
Homa Boms ◽  
Thomas Fink ◽  
Roberto Cabeza
Keyword(s):  
Older Adults ◽  
Functional Connectivity ◽  
Structural Equation ◽  
Healthy Aging ◽  
Memory Performance ◽  
Structural Connectivity ◽  
Equation Modeling ◽  
Cognitive Changes ◽  
Age Related ◽  
The Relationship

Understanding the precise relation between functional connectivity and structural (white matter) connectivity and how these relationships account for cognitive changes in older adults are major challenges for neuroscience. We investigate these issues using an approach in which structural equation modeling (SEM) is employed to integrate functional and structural connectivity data from younger and older adults ( n = 62), analyzed with a common framework based on regions connected by canonical tract groups (CTGs). CTGs (e.g., uncinate fasciculus) serve as a common currency between functional and structural connectivity matrices, and ensure equivalent sparsity in connectome information. We used this approach to investigate the neural mechanisms supporting memory for items and memory for associations, and how they are affected by healthy aging. We found that different structural and functional CTGs made independent contributions to source and item memory performance, suggesting that both forms of connectivity underlie age-related differences in specific forms of memory. Furthermore, the relationship between functional and structural connectivity was best explained by a general relationship between latent constructs—a relationship absent in any specific CTG group. These results provide insights into the relationship between structural and functional connectivity patterns, and elucidate their relative contribution to age-related differences in source memory performance.

Linking perceived organizational support for strengths use to task performance

2020 ◽  
Vol 48 (3) ◽  
pp. 1-10 ◽  
Author(s):  
He Ding ◽  
Enhai Yu ◽  
Yanbin Li
Keyword(s):  
Positive Affect ◽  
Task Performance ◽  
Organizational Support ◽  
Structural Equation ◽  
Perceived Organizational Support ◽  
Equation Modeling ◽  
Strengths Use ◽  
Managerial Implications ◽  
The Relationship ◽  
And Task

We investigated the mediating effects of positive affect and strengths use in the relationship between perceived organizational support for strengths use (POSSU) and employees' task performance. Data were gathered at 2 time points, separated by a 2-week interval, from 157 employees working in various Chinese enterprises. We applied structural equation modeling and PROCESS macro analysis to the data. The results indicate that POSSU was positively related to task performance and that this relationship was mediated by strengths use. In addition, positive affect and strengths use played a sequential mediating role in the relationship between POSSU and task performance. However, positive affect was not a significant mediator in the POSSU–task performance relationship. Theoretical and managerial implications are discussed in the context of the literature on POSSU and task performance.

Role of burnout on job level, job satisfaction, and task performance

2017 ◽  
Vol 38 (5) ◽  
pp. 630-645 ◽  
Author(s):  
Won Ho Kim ◽  
Young-An Ra ◽  
Jong Gyu Park ◽  
Bora Kwon
Keyword(s):  
Job Satisfaction ◽  
Task Performance ◽  
Organizational Context ◽  
Content Type ◽  
Job Level ◽  
Mediating Role ◽  
Final Sample ◽  
The Relationship ◽  
And Task

Purpose The purpose of this paper is to examine the mediating role of burnout (i.e. exhaustion, cynicism, professional inefficacy) in the relationship between job level and job satisfaction as well as between job level and task performance. Design/methodology/approach The final sample included 342 Korean workers from selected companies. The authors employed the Hayes (2013) PROCESS tool for analyzing the data. Findings The results showed that all three subscales of burnout (i.e. exhaustion, cynicism, professional inefficacy) mediate the relationship between job level and job satisfaction. However, only two mediators (i.e. cynicism, professional inefficacy) indicated the mediating effects on the association between job level and task performance. Originality/value This research presented the role of burnout on the relationships between job level, job satisfaction, and task performance especially in South Korean organizational context. In addition to role of burnout, findings should prove helpful in improving job satisfaction and task performance. The authors provide implications and limitations of the findings.

scholarly journals Post-Drive Standing Balance of Vehicle Passengers Using Wearable Sensors: The Effect of On-Road Driving and Task Performance

Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 4997
Author(s):  
Victor C. Le ◽  
Monica L. H. Jones ◽  
Kathleen H. Sienko
Keyword(s):  
Task Performance ◽  
Postural Sway ◽  
Wearable Sensors ◽  
Standing Balance ◽  
Balance Performance ◽  
Real Time Traffic ◽  
Balance Exercises ◽  
Before And After ◽  
The Relationship ◽  
And Task

Postural sway has been demonstrated to increase following exposure to different types of motion. However, limited prior studies have investigated the relationship between exposure to normative on-road driving conditions and standing balance following the exposure. The purpose of this on-road study was to quantify the effect of vehicle motion and task performance on passengers’ post-drive standing balance performance. In this study, trunk-based kinematic data were captured while participants performed a series of balance exercises before and after an on-road driving session in real-time traffic. Postural sway for all balance exercises increased following the driving session. Performing a series of ecologically relevant visual-based tasks led to increases in most post-drive balance metrics such as sway position and velocity. However, the post-drive changes following the driving session with a task were not significantly different compared to changes observed following the driving session without a task. The post-drive standing balance performance changes observed in this study may increase vulnerable users’ risk of falling. Wearable sensors offer an opportunity to monitor postural sway following in-vehicle exposures.

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