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

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.

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

10.1101/144154 ◽

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.

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INVESTIGATING MODERATORS OF THE RELATIONSHIP BETWEEN SUBJECTIVE AND OBJECTIVE MEMORY

Innovation in Aging ◽

10.1093/geroni/igz038.158 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S40-S41

Author(s):

Francesca Falzarano ◽

Jillian Minahan ◽

Karen L Siedlecki ◽

Timothy Salthouse

Keyword(s):

Older Adults ◽

At Risk ◽

Cognitive Aging ◽

Structural Equation ◽

Memory Performance ◽

Likelihood Estimation ◽

Equation Modeling ◽

Depression And Anxiety ◽

Affective Factors ◽

The Relationship

Abstract Subjective memory complaints (SMC) among older adults have been explored as an indicator of decline in objective memory functioning. While some research has found that SMC may be predictive of future cognitive impairment and dementia (Glodzik-Sobanska et al., 2007; Wang et al., 2004), others have suggested that SMC are common among healthy older adults (Cooper et al., 2011) and are not strongly related to objective memory performance. Researchers suggest that SMC may be more strongly related to affective factors (e.g., depression and anxiety; Rowell, Green, Teachman, & Salthouse, 2015). The current study examined the relationship between SMC, objective episodic memory performance (OEMP), along with depression and anxiety in a sample of 18-99 year olds (N = 5,430) from the Virginia Cognitive Aging Project (VCAP). Structural equation modeling with full information maximum likelihood estimation was used to investigate whether clinically-relevant depression and anxiety levels moderated the relationship between SMC and OEMP, controlling for age, education, gender, and health. OEMP was represented as a latent construct while the remaining variables were observed. Although depression and anxiety are significantly related to SMC (r’s = .29, .17, respectively), they are not correlated with OEMP. Furthermore, depression, but not anxiety, moderated the relationship between SMC and OEMP, such that those at risk for depression had a stronger relationship between SMC and OEMP (-.07, p<.05) compared to those not at risk (-.02, p=.31). This suggests that SMC may not be a valid indicator of OEMP as it may reflect variance from other sources, such as depression.

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The influence of age on the job resources-engagement relationship

International Journal of Organizational Analysis ◽

10.1108/ijoa-09-2018-1528 ◽

2019 ◽

Vol 27 (4) ◽

pp. 1218-1238 ◽

Cited By ~ 2

Author(s):

Wei Ning ◽

Albi Alikaj

Keyword(s):

Work Engagement ◽

Structural Equation ◽

Job Resources ◽

Equation Modeling ◽

Content Type ◽

Work Arrangements ◽

Older Employees ◽

Age Related ◽

Employee Work Engagement ◽

The Relationship

PurposeThe purpose of this paper is to examine the moderating role of employee age in the relationship between work engagement and several job resources.Design/methodology/approachThe study used questionnaire-based surveys completed by 804 employees from firms located in West China. The data were then analyzed by conducting latent moderated structural equation modeling.FindingsThe results of the study show that certain job resources (autonomy, recognition, colleague support, participation, job security and flexible work arrangements) are more effective for older employees in promoting work engagement, while other resources (job feedback, opportunities for development, skill variety and internal promotion) are more tailored toward younger employees.Research limitations/implicationsThe results suggest that job resources are not equally effective in affecting employee work engagement. Therefore, future studies should adopt a dynamic lifespan perspective when studying the relationship between job resources and work engagement.Practical implicationsThe current study indicates that to increase younger employees’ work engagement, organizations need to rely more on development-oriented job resources, and to increase older employees’ work engagement, they need to focus more on maintenance-oriented resources.Originality/valueThe literature on work engagement has assumed that the strength of the relationship between job resources and work engagement is uniform among employees at all ages. This study refers to two life-span theories from the development psychology literature to explain that there are age-related differences in the effect of job resources on employee work engagement.

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Modeling Longitudinal Relationships Between Habit and Physical Activity: Two Cross-Lagged Panel Design Studies in Older Adults

Journal of Aging and Physical Activity ◽

10.1123/japa.2016-0212 ◽

2017 ◽

Vol 25 (3) ◽

pp. 464-473 ◽

Cited By ~ 3

Author(s):

Rob J.H. van Bree ◽

Catherine Bolman ◽

Aart N. Mudde ◽

Maartje M. van Stralen ◽

Denise A. Peels ◽

...

Keyword(s):

Physical Activity ◽

Older Adults ◽

Structural Equation ◽

Functional Limitations ◽

Equation Modeling ◽

Design Studies ◽

Mediation Effects ◽

Measurement Results ◽

The Relationship ◽

Longitudinal Relationships

These longitudinal studies in older adults targeted mediated relationships between habit and physical activity (PA). In The Netherlands two independent studies were conducted among 1976 (Study 1: Mage = 63.63, SD = 8.66, 30% functional limitations) and 2140 (Study 2: Mage = 62.75, SD = 8.57, 45% functional limitations) adults aged 50 years or older. Cross-lagged panel designs were applied to examine whether habit mediates the relationship between prior and later PA and whether PA simultaneously mediates the relationship between prior and later habit. Data on habit and PA were collected by means of questionnaires at baseline (t0) and at 6 (t1) and 12 (t2) months after baseline measurement. Results of structural equation modeling analyses were not unambiguous. Indications for the existence of both hypothesized mediation effects were found, but no clear, unequivocal pattern appeared. Somewhat more support was found for the PA-habit-PA path than for the habit-PA-habit path. More research is needed to draw more definitive conclusions.

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Fronto-striatal Functional Connectivity Supports Reward-Enhanced Memory in Older Adults

10.1101/592501 ◽

2019 ◽

Author(s):

Holly J. Bowen ◽

Jaclyn H. Ford ◽

Cheryl L. Grady ◽

Julia Spaniol

Keyword(s):

Older Adults ◽

Functional Connectivity ◽

Healthy Aging ◽

Inferior Frontal Gyrus ◽

Neural Mechanisms ◽

Neural Activation ◽

Younger Adults ◽

Age Related ◽

High Reward ◽

Neural Underpinnings

AbstractBoth younger and older adults prioritize reward-associated stimuli in memory, but there has been little research on possible age differences in the neural mechanisms mediating this effect. In the current study, we examine neural activation and functional connectivity in healthy younger and older adults to test the hypothesis that older adults would engage prefrontal regions to a greater extent in the service of reward-enhanced memory. While undergoing MRI, target stimuli were presented after high or low-reward cues. The cues indicated the reward value for successfully recognizing the stimulus on a memory test 24-hours later. We replicated prior findings that both older and younger and adults had better memory for high compared to low-reward stimuli. Critically, in older, but not younger adults, this enhanced subsequent memory for high-reward items was supported by greater connectivity between the caudate and bilateral inferior frontal gyrus. The findings add to the growing literature on motivation-cognition interactions in healthy aging, and provide novel evidence of an age-related shift in the neural underpinnings of reward-motivated encoding.

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Alpha Phase Dynamics Predict Age-Related Visual Working Memory Decline

10.1101/050450 ◽

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.

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Social Capital and Self-Rated Health among Older Adults Living in Urban China: A Mediation Model

Sustainability ◽

10.3390/su11205566 ◽

2019 ◽

Vol 11 (20) ◽

pp. 5566 ◽

Cited By ~ 2

Author(s):

Nan Lu ◽

Jingyue Zhang

Keyword(s):

Older Adults ◽

Social Capital ◽

Living Arrangements ◽

Structural Equation ◽

Healthy Aging ◽

Urban China ◽

Equation Modeling ◽

Self Rated Health ◽

Cognitive Social Capital ◽

Structural Social Capital

Social capital and healthy aging are both crucial for social sustainability in China. The present study tested the role of structural social capital in self-rated health among older urban Chinese adults and the influence of cognitive social capital on this relationship. A sample of 456 older adults aged 60 or older in Suzhou, China, were recruited and completed the survey in 2015. Structural equation modeling was used to test the proposed model. Cognitive social capital had larger effects on self-rated health than structural social capital. The relationship between structural social capital and self-rated health was fully mediated by cognitive social capital, when sociodemographic characteristics, socioeconomic status, physical health conditions, and living arrangements were controlled. The culturally sensitive latent construct of community-based social capital proved to be a valid instrument in urban Chinese contexts. Structural social capital likely indirectly affects self-rated health through cognitive social capital. Policy and intervention implications are discussed.

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Does Self-Efficacy and Team Leader Equity Matter for Older Workers’ Mental Health?

The Gerontologist ◽

10.1093/geront/gnz191 ◽

2020 ◽

Vol 60 (6) ◽

pp. 996-1004 ◽

Cited By ~ 1

Author(s):

Mi Sun Choi ◽

Holly Dabelko-Schoeny ◽

Mo Yee Lee ◽

Alicia C Bunger

Keyword(s):

Mental Health ◽

Older Adults ◽

Work Engagement ◽

Older Workers ◽

Self Efficacy ◽

Structural Equation ◽

Working Life ◽

Team Leader ◽

Equation Modeling ◽

The Relationship

Abstract Background and Objectives Prolonged working life is not necessarily associated with good mental health. Despite the importance of healthy working life in later years, little research has been conducted on predictors of mental health in the workplace among older workers. This study aimed to investigate how personal (self-efficacy) and team (leader equity) factors are associated with older workers’ mental health through work engagement. Research Design and Methods We analyzed responses of 508 U.S. workers aged 50 years and older from the Age and Generations Study data using structural equation modeling. Results Results showed that perceived self-efficacy was a strong predictor of mental health. Also, work engagement was a powerful mechanism for promoting older adults’ mental health; engagement partially mediated the relationship between perceived self-efficacy and mental health, and fully mediated the relationship between team leader equity and mental health. Discussion and Implications The findings highlight how important it is for employers to invest in human capital development, suggesting human resource programs should focus on strategies that target older adults’ engagement through tailored self-efficacy programs and inclusive leadership training programs. Such attempts would contribute to enhancing the mental health of older workers.

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Fall-related Injuries Mediate the Relationship between Self-Reported Hearing Loss and Mortality in Middle-Aged and Older Adults

The Journals of Gerontology Series A ◽

10.1093/gerona/glab123 ◽

2021 ◽

Author(s):

Dongjuan Xu ◽

Melissa D Newell ◽

Alexander L Francis

Keyword(s):

Older Adults ◽

Hearing Loss ◽

Structural Equation ◽

Equation Modeling ◽

Middle Aged ◽

Risk Of Death ◽

Risk Of Injury ◽

Increased Risk ◽

The Relationship ◽

Hearing Problems

Abstract Background Hearing loss is associated with a greater risk of death in older adults. This relationship has been attributed to an increased risk of injury, particularly due to falling, in individuals with hearing loss. However, the link between hearing loss and mortality across the lifespan is less clear. Methods We used structural equation modeling and mediation analysis to investigate the relationship between hearing loss, falling, injury, and mortality across the adult lifespan in public-use data from the National Health Interview Survey and the National Death Index. We examined 1) the association between self-reported hearing problems and later mortality, 2) the associations between self-reported hearing problems and the risk of injury and degree and type of injury, 3) the mediating role of falling and injury in the association between self-reported hearing problems and mortality, and 4) whether these relationships differ in young (18-39), middle-aged (40-59) and older (60+) age groups. Results In all three age ranges, those reporting hearing problems were more likely to fall, were more likely to sustain an injury, and were more likely to sustain a serious injury, than those not reporting hearing problems. While there was no significant association between hearing loss and mortality in the youngest category, there was for middle-aged and older participants and for both fall-related injury was a significant mediator in this relationship. Conclusions Fall-related injury mediates the relationship between hearing loss and mortality for middle-aged as well as older adults, suggesting a need for further research into mechanisms and remediation.

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SELF-EFFICACY AND TEAM LEADER EQUITY MATTER: A STUDY OF ACTIVE AGING AT WORK

Innovation in Aging ◽

10.1093/geroni/igz038.2808 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S764-S764

Author(s):

Mi Sun Choi ◽

Holly Dabelko-Schoeny ◽

Mo Yee Lee ◽

Alicia Bunger

Keyword(s):

Mental Health ◽

Older Adults ◽

Human Resource ◽

Older Workers ◽

Self Efficacy ◽

Structural Equation ◽

Well Being ◽

Equation Modeling ◽

Active Aging ◽

The Relationship

Abstract Many older Americans have decided to remain in the labor market beyond the traditional retirement age, suggesting the need for companies to consider human resource initiatives to retain and support the aging workforce. Applying active aging concepts, which emphasize older adults’ active roles through participation in social and economic activities for healthy later life, to the workplace could be helpful for developing programs that enhance the health, well-being, and work outcomes of older workers. Despite the expected benefits of active aging at work for older workers’ overall well-being, little research has been conducted on what personal and team factors impact on outcomes of active aging at work; what mechanism exists in the links between factors and outcomes in the contemporary workplace. The current study tested the validity of an active aging framework using the Age and Generations Study data. We analyzed responses of 508 American workers aged 50 and older using structural equation modeling. Results showed that perceived self-efficacy was a strong predictor of engagement, mental health, and performance, whereas perceived leader equity predicted only engagement. Also, work engagement was powerful mechanism for promoting older adults’ mental health; engagement mediated the relationship between perceived self-efficacy and the relationship between leader equity and mental health. The findings highlight how important it is for employers to invest in human capital, suggesting human resource programs should focus on strategies that target older adults’ engagement through tailored self-efficacy programs and diversity leadership training programs. Such attempts would contribute to the well-being of older workers.

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