Selective decline in memory function among healthy elderly

Childhood adversities and memory function in later life: the mediating role of activity participation

BACKGROUND

Childhood adversities may lead to decreased activity participation in later life, impacting memory health in ageing adults. Childhood adversities related to deprivation and threat, as conceptualized by the Dimensional Model of Adversity, can exhibit distinct impacts on cognitive and emotional outcomes in children and younger adults. This study examined the potential influence of childhood deprivation and threat on memory function in later life and the mediating role of activity participation in these relationships.

METHODS

This study used data from the first wave of Panel Study of Active Ageing and Society (PAAS), a representative survey of Hong Kong residents aged 50 or above (N = 1,005). Key variables included late-life memory function measured by delayed recall test, deprivation- and threat-related childhood adversities, and the frequency of participation in informal and formal types of activities. Mediation tests were used for analysis.

RESULTS

Childhood deprivation was associated with a lower late-life memory function, whereas threat was not. The negative effects of childhood deprivation and its subdomain, economic hardship, on memory function were mediated by activity participation. Total participation scores presented the strongest mediating effect (17.3-20.6%), with formal activities playing a more substantial mediating role than informal activities in mitigating the effect of childhood deprivation.

CONCLUSIONS

These findings expand the applicability of the Dimensional Model of Adversity to ageing populations, highlighting the influence of deprivation on life-long cognitive development. Furthermore, this study revealed an indirect mechanism by which childhood deprivation affects memory health in old age through diverse activity participation.

Improved speech intelligibility in the presence of congruent vibrotactile speech input

Vibrotactile stimulation is believed to enhance auditory speech perception, offering potential benefits for cochlear implant (CI) users who may utilize compensatory sensory strategies. Our study advances previous research by directly comparing tactile speech intelligibility enhancements in normal-hearing (NH) and CI participants, using the same paradigm. Moreover, we assessed tactile enhancement considering stimulus non-specific, excitatory effects through an incongruent audio-tactile control condition that did not contain any speech-relevant information. In addition to this incongruent audio-tactile condition, we presented sentences in an auditory only and a congruent audio-tactile condition, with the congruent tactile stimulus providing low-frequency envelope information via a vibrating probe on the index fingertip. The study involved 23 NH listeners and 14 CI users. In both groups, significant tactile enhancements were observed for congruent tactile stimuli (5.3% for NH and 5.4% for CI participants), but not for incongruent tactile stimulation. These findings replicate previously observed tactile enhancement effects. Juxtaposing our study with previous research, the informational content of the tactile stimulus emerges as a modulator of intelligibility: Generally, congruent stimuli enhanced, non-matching tactile stimuli reduced, and neutral stimuli did not change test outcomes. We conclude that the temporal cues provided by congruent vibrotactile stimuli may aid in parsing continuous speech signals into syllables and words, consequently leading to the observed improvements in intelligibility.

Association of Cognitive Polygenic Index and Cognitive Performance with Age in Cognitively Healthy Adults

Genome-wide association studies have discovered common genetic variants associated with cognitive performance. Polygenic scores that summarize these discoveries explain up to 10% of the variance in cognitive test performance in samples of adults. However, the role these genetics play in cognitive aging is not well understood. We analyzed data from 168 cognitively healthy participants aged 23-77 years old, with data on genetics, neuropsychological assessment, and brain-imaging measurements from two large ongoing studies, the Reference Abilities Neural Networks, and the Cognitive Reserve study. We tested whether a polygenic index previously related to cognition (Cog PGI) would moderate the relationship between age and measurements of the cognitive domains extracted from a neuropsychological evaluation: fluid reasoning, memory, vocabulary, and speed of processing. We further explored the relationship of Cog PGI and age on cognition using Johnson-Neyman intervals for two-way interactions. Sex, education, and brain measures of cortical thickness, total gray matter volume, and white matter hyperintensity were considered covariates. The analysis controlled for population structure-ancestry. There was a significant interaction effect of Cog PGI on the association between age and the domains of memory (Standardized coefficient = -0.158, p-value = 0.022), fluid reasoning (Standardized coefficient = -0.146, p-value = 0.020), and vocabulary (Standardized coefficient = -0.191, p-value = 0.001). Higher PGI strengthened the negative relationship between age and the domains of memory and fluid reasoning while PGI weakened the positive relationship between age and vocabulary. Based on the Johnson-Neyman intervals, Cog PGI was significantly associated with domains of memory, reasoning, and vocabulary for younger adults. There is a significant moderation effect of genetic predisposition for cognition for the association between age and cognitive performance. Genetics discovered in genome-wide association studies of cognitive performance show a stronger association in young and midlife older adults.

Pet ownership and maintenance of cognitive function in community-residing older adults: evidence from the Baltimore Longitudinal Study of Aging (BLSA)

Pet ownership has been associated with reduced deterioration in physical health as older adults age; little research focused on deterioration in cognitive function. We examine the relationship of pet, dog, cat ownership, and dog walking to changes in cognitive function among 637 generally healthy community-dwelling older adults (185 pet owners) aged 50-100 years (M = 68.3, SD = 9.6) within the BLSA. Cognitive assessments every 1-4 years over 1-13 years (M = 7.5, SD = 3.6) include the California Verbal Learning (Immediate, Short, Long Recall); Benton Visual Retention; Trail-Making (Trails A, B, B-A); Digit Span; Boston Naming (Naming); and Digit Symbol Substitution (Digit Symbol) Tests. In linear mixed models, deterioration in cognitive function with age was slower for pet owners than non-owners (Immediate, Short, Long Recall; Trails A,B,B-A; Naming; Digit Symbol); dog owners than non-owners (Immediate, Short Recall; Trails A,B; Naming; Digit Symbol); and cat owners than non-owners (Immediate, Short, Long Recall; Naming), controlling for age and comorbidities. Among dog owners (N = 73) walkers experienced slower deterioration than non-walkers (Trails B, B-A; Short Recall). All ps ≤ 0.05. We provide important longitudinal evidence that pet ownership and dog walking contribute to maintaining cognitive function with aging and the need to support pet ownership and dog walking in design of senior communities and services.

Integrating Nutrient Biomarkers, Cognitive Function, and Structural MRI Data to Build Multivariate Phenotypes of Healthy Aging

BACKGROUND

Research in the emerging field of Nutritional Cognitive Neuroscience demonstrates that many aspects of nutrition - from entire diets to specific nutrients - affect cognitive performance and brain health.

OBJECTIVE

While prior research has primarily examined the bivariate relationship between nutrition and cognition, or nutrition and brain health, the present study sought to investigate the joint relationship between these essential and interactive elements of human health.

METHODS

We applied a state-of-the-art data fusion method, Coupled Matrix Tensor Factorization, to characterize the joint association between measures of nutrition (52 nutrient biomarkers), cognition (Wechsler Abbreviated Test of Intelligence and Wechsler Memory Scale), and brain health (high-resolution Magnetic Resonance Imaging measures of structural brain volume) within a cross-sectional sample of 111 healthy older adults that had an average age of 69.1 years, were 62% female and had an average Body Mass Index of 26.0.

RESULTS

Data fusion uncovered 3 latent factors that capture the joint association between specific nutrient profiles, cognitive measures, and cortical volumes, demonstrating the respects in which these health domains are coupled. Hierarchical cluster analysis further revealed systematic differences between the observed latent factors, providing evidence for multivariate phenotypes that represent high versus low levels of performance across multiple health domains. The primary features that distinguish between each phenotype were: (i) nutrient biomarkers for monounsaturated and polyunsaturated fatty acids; (ii) cognitive measures of immediate, auditory, and delayed memory; and (iii) brain volumes within frontal, temporal, and parietal cortex.

CONCLUSIONS

By incorporating innovations in nutritional epidemiology (nutrient biomarker analysis), cognitive neuroscience (high-resolution structural brain imaging), and statistics (data fusion), the present study provides an interdisciplinary synthesis of methods that elucidate how nutrition, cognition, and brain health are integrated through lifestyle choices that affect healthy aging.

Childhood deprivations predict late-life cognitive impairment among older adults in India

Large population-based studies on the associations of childhood factors with late-life cognition are lacking in many low and middle income countries including India. In this study, we assessed the prevalence of late-life cognitive impairment and examined the associations of childhood socioeconomic status (SES) and health conditions with cognitive impairment among older adults in India. Data for this study were derived from the Longitudinal Ageing Study in India conducted in 2017-18. The effective sample size was 31,464 older adults aged 60 years and above. Cognitive functioning was measured through five global domains (memory, orientation, arithmetic function, executive function, and object naming). The overall score ranged between 0 and 43, and the score was reversed indicating cognitive impairment. Descriptive statistics along with mean scores of cognitive impairment were presented. Additionally, moderated multivariable linear regression models were employed to examine the association between explanatory variables, including childhood SES and health conditions and late-life cognitive impairment. The mean score of cognitive functioning among the study participants was 21.72 (CI 2.64-21.80). About 15% of older adults had poor health conditions, and 44% had lower financial status during their childhood. Older adults who had a fair health during their childhood were more likely to suffer from cognitive impairment in comparison to older adults who had good health during their childhood (Coef: 0.60; CI 0.39, 0.81). In comparison to older adults who had good childhood financial status, those who had poor childhood financial status were more likely to suffer from cognitive impairment (Coef: 0.81; CI 0.56, 1.07). Older adults who had fair childhood health status and poor childhood financial status were more likely to suffer from cognitive impairment in comparison to older adults who had good childhood health and good financial status (Coef: 1.26; CI 0.86, 1.66). Social policies such as improving educational and financial resources in disadvantaged communities and socioeconomically poor children and their families, would help to enhance a better cognitive ageing and a healthy and dignified life in old age.

Trans-ethnic Meta-analysis of Interactions between Genetics and Early Life Socioeconomic Context on Memory Performance and Decline in Older Americans

Later life cognitive function is influenced by genetics as well as early- and later-life socioeconomic context. However, few studies have examined the interaction between genetics and early childhood factors. Using gene-based tests (iSKAT/iSKAT-O), we examined whether common and/or rare exonic variants in 39 gene regions previously associated with cognitive performance, dementia, and related traits had an interaction with childhood socioeconomic context (parental education and financial strain) on memory performance or decline in European ancestry (EA, N=10,468) and African ancestry (AA, N=2,252) participants from the Health and Retirement Study. Of the 39 genes, 22 in EA and 19 in AA had nominally significant interactions with at least one childhood socioeconomic measure on memory performance and/or decline; however, all but one (father's education by SLC24A4 in AA) were not significant after multiple testing correction (FDR <0.05). In trans-ethnic meta-analysis, two genes interacted with childhood socioeconomic context (FDR <0.05): mother's education by MS4A4A on memory performance, and father's education by SLC24A4 on memory decline. Both interactions remained significant (p<0.05) after adjusting for respondent's own educational attainment, APOE ε4 status, lifestyle factors, BMI, and comorbidities. For both interactions in EA and AA, the genetic effect was stronger in participants with low parental education. Examination of common and rare variants in genes discovered through GWAS shows that childhood context may interact with key gene regions to jointly impact later life memory function and decline. Genetic effects may be more salient for those with lower childhood socioeconomic status.

Effects of aging on conditional visuomotor learning for grasping and lifting eccentrically weighted objects

Explicit knowledge of object center of mass or CM location fails to guide anticipatory scaling of digit forces necessary for dexterous manipulation. We previously showed that allowing young adults to choose where to grasp the object entailed an ability to use arbitrary color cues about object CM location to gradually minimize object tilt across several trials. This conditional learning was achieved through accurate anticipatory modulation of digit position using the color cues. However, it remains unknown how aging affects the ability to use explicit color cues about object CM location to modulate digit placement for dexterous manipulation. We instructed healthy older and young adults to learn a manipulation task using arbitrary color cues about object CM location. Subjects were required to exert clockwise, counterclockwise, or no torque on the object according to the color cue and lift the object while minimizing its tilt. Older adults produced larger torque error during conditional learning trials, resulting in a slower rate of learning than young adults. Importantly, older adults showed impaired anticipatory modulation of digit position when information of the CM location was available via explicit color cues. The older adults also did not modulate their digit forces to compensate for this impairment. Interestingly, however, anticipatory modulation of digit position was intact in the same individuals when information of object CM location was implicitly conveyed from trial-to-trial. We discuss our findings in relation to age-dependent changes in processes and neural network essential for learning dexterous manipulation using arbitrary color cue about object property.NEW & NOTEWORTHY We studied whether older adults are able to predictively modulate digit position using arbitrary color cues indicating object center of mass location for dexterous manipulation. Older adults showed an impaired ability to modulate digit position using the color cues when compared with young adults. Interestingly, similar impairments were not found when same older individuals learned the task using implicit knowledge. Our findings suggest an age-related impairment specifically in the conditional learning mechanisms for dexterous manipulation.

The Effect of Childhood Socioeconomic Position and Social Mobility on Cognitive Function and Change Among Older Adults: A Comparison Between the United States and England

OBJECTIVES

This study aims to examine the relationship between childhood socioeconomic position (SEP) and cognitive function in later life within nationally representative samples of older adults in the United States and England, investigate whether these effects are mediated by later-life SEP, and determine whether social mobility from childhood to adulthood affects cognitive function and decline.

METHOD

Using data from the Health and Retirement Study (HRS) and the English Longitudinal Survey of Ageing (ELSA), we examined the relationships between measures of SEP, cognitive performance and decline using individual growth curve models.

RESULTS

High childhood SEP was associated with higher cognitive performance at baseline in both cohorts and did not affect the rate of decline. This benefit dissipated after adjusting for education and adult wealth in the United States. Respondents with low childhood SEP, above median education, and high adult SEP had better cognitive performance at baseline than respondents with a similar childhood background and less upward mobility in both countries.

DISCUSSION

These findings emphasize the impact of childhood SEP on cognitive trajectories among older adults. Upward mobility may partially compensate for disadvantage early in life but does not protect against cognitive decline.

Dietary lutein and zeaxanthin are associated with working memory in an older population

OBJECTIVE

The purpose of the study was to examine the association between dietary lutein and zeaxanthin (L + Z) intake and immediate word recall (IWR) and delayed word recall (DWR), and to identify the major contributors to dietary L + Z intake in a recent and representative sample of the older US population.

DESIGN

In this cross-sectional analysis, multivariate path analytic models estimated the association between L + Z consumption and cognitive performance while adjusting for covariates.

SETTING

Observations were drawn from the 2014 Health and Retirement Study, a nationally representative panel study of older US adults, and the 2013 Health Care and Nutrition Study, which assessed dietary intake via FFQ in a subsample of respondents.

PARTICIPANTS

The analytic sample included 6390 respondents aged ≥50 years.

RESULTS

L + Z intake was 2·44 ± 2·32 mg/d on average, and L + Z intake differed significantly across quartiles (P < 0·001). For example, average L + Z intake in Q1 was 0·74 ± 0·23 mg/d and in Q4 was 5·46 ± 2·88 mg/d. In covariate adjusted models, older adults in the highest quartiles of L + Z intake had significantly greater IWR and DWR scores than those in the lowest quartile. Leafy vegetables, cruciferous vegetables, dark yellow vegetables, fish and seafood, legumes, eggs and fruit were significant and meaningful predictors of dietary L + Z intake.

CONCLUSION

A high consumption of vegetables, fish and seafood, legumes, eggs and fruit is associated with a higher intake of L + Z and greater word recall among older adults.

Association of Cognitive Function Trajectories in Centenarians With Postmortem Neuropathology, Physical Health, and Other Risk Factors for Cognitive Decline

IMPORTANCE

Understanding mechanisms associated with prolonged cognitive health in combination with exceptional longevity might lead to approaches to enable successful aging.

OBJECTIVE

To investigate trajectories of cognitive functioning in centenarians across domains, and to examine the association of these trajectories with factors underlying cognitive reserve, physical health, and postmortem levels of Alzheimer disease (AD)-associated neuropathology.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used neuropsychological test data and postmortem neuropathological reports from Dutch centenarians who were drawn from the 100-plus Study between January 2013 and April 2019. Eligible participants self-reported being cognitively healthy, which was confirmed by a proxy. Data analysis was performed between June 2019 and June 2020.

EXPOSURES

Age, sex, APOE ε genotype, factors of cognitive reserve, physical health, and AD-associated neuropathology (ie, amyloid-β, neurofibrillary tangles, and neuritic plaques).

MAIN OUTCOMES AND MEASURES

In annual visits (until death or until participation was no longer possible), centenarians underwent an extensive neuropsychological test battery, from which an mean z score of global cognition, memory, executive functions, verbal fluency, visuospatial functions, and attention/processing speed was calculated. Linear mixed models with a random intercept and time as independent variable were used to investigate cognitive trajectories, adjusted for sex, age, education, and vision and hearing capacities. In a second step, linear mixed models were used to associate cognitive trajectories with factors underlying cognitive reserve, physical health at baseline, and AD-associated neuropathology.

RESULTS

Of the 1023 centenarians approached, 340 were included in the study. We analyzed 330 centenarians for whom cognitive tests were available at baseline (239 [72.4%] women; median [interquartile range] age of 100.5 [100.2-101.7] years), with a mean (SD) follow-up duration of 1.6 (0.8) years. We observed no decline across investigated cognitive domains, with the exception of a slight decline in memory function (β, -0.10 SD per year; 95% CI, -0.14 to -0.05 SD; P < .001). Cognitive performance was associated with factors of physical health (eg, higher Barthel index: β, 0.37 SD per year; 95% CI, 0.24-0.49; P < .001) and cognitive reserve (eg, higher education: β, 0.41 SD per year; 95% CI, 0.29-0.53; P < .001), but none of these factors were associated with the rate of decline. Neuropathological reports were available for 44 participants. While centenarian brains revealed varying loads of postmortem neuropathological hallmarks of AD, this was not associated with cognitive performance or rate of decline.

CONCLUSIONS AND RELEVANCE

While we observed a slight vulnerability for decline in memory function, centenarians maintained high levels of performance in all other investigated cognitive domains for up to 4 years despite the presence of risk factors of cognitive decline. These findings suggest that mechanisms of resilience may underlie the prolongation of cognitive health until exceptional ages.

Cardiorespiratory fitness, hippocampal subfield volumes, and mnemonic discrimination task performance in aging

Aging and exercise have opposing effects on mnemonic discrimination task performance, which putatively taxes pattern separation mechanisms reliant on the dentate gyrus (DG) subfield of the hippocampus. In young adults, increasing cardiorespiratory fitness (CRF) has been shown to improve mnemonic discrimination task performance and increase left anterior DG/CA3 volume. It is unknown how these variables interact in cognitive aging, yet this knowledge is critical, given the established effects of aging on hippocampal plasticity. To investigate these relationships, 65 older adults (aged 55–85 years) completed a submaximal treadmill test to estimate CRF, a mnemonic discrimination task, and a high‐resolution MRI scan to determine hippocampal subfield volumes. Our older adult sample demonstrated the lowest task accuracy in the condition with the greatest stimuli similarity and left DG/CA3 body volume significantly predicted accuracy in this condition. Our results did not provide support for relationships between CRF and task accuracy or CRF and DG/CA3 volume as evidenced in studies of young adults. Instead, CRF predicted bilateral subiculum volume in older adult women, not men. Altogether, these findings provide further support for a role of the DG in behavioral pattern separation in humans and suggest that CRF may have differential effects on hippocampal subfield integrity in older adult men and women. ClinicalTrials.gov identifiers: (a) Neuroimaging Study of Exercise and Memory Function, NCT02057354; (b) The Entorhinal Cortex and Aerobic Exercise in Aging, NCT02775760; (c) Physical Activity and Cognition Study, NCT02773121.

Changes in Spatial Working Memory in Stable Chronic Obstructive Pulmonary Disease: A Retrospective Study

Chronic obstructive pulmonary disease (COPD) is characterized by irreversible airflow limitation and is often accompanied by cognitive impairment. Little is known about the working memory of COPD patients. The aim of the study is to evaluate the spatial working memory of COPD patients using the classical visuospatial working memory neuropsychological paradigms. This was a retrospective study of patients with COPD who were evaluated for neurocognitive functions between February and December 2018 at Hefei Second People's Hospital. Healthy controls (HC) were included. The neuropsychological tests included the Beijing Version of the Montreal Cognitive Assessment Test (MoCA), digit span test (DS), Chinese Auditory Verbal Learning Test (CAVLT), Stroop test, and Verbal Fluency Test (VFT). The COPD group performed worse in MoCA (22.3 ± 4.5 vs. 26.1 ± 2.9, P < 0.001), Stroop interference test (44.2 ± 16.9 vs. 36.8 ± 10.3, P = 0.038), and VFT (12.9 ± 2.8 vs. 15.3 ± 4.7, P = 0.021) vs. the HC group. Compared with the HC group, COPD patients had statistically significant differences with respect to 0-back RT (657 ± 46 vs. 578 ± 107, P = 0.001), 1-back accuracy (41.8 ± 12.1% vs. 81.5 ± 18.1%, P < 0.001), 1-back RT (592 ± 75 vs. 431 ± 138, P < 0.001), 2-back accuracy (31.4 ± 9.9% vs. 68.1 ± 16.6%, P < 0.001), and 2-back RT (563 ± 79 vs. 455 ± 153, P = 0.002). Only PaO₂ was independently associated with 0-back RT (B = 0.992 ± 0.428, P = 0.028) and 1-back ACC (B = 0.003 ± 0.001, P = 0.004). COPD patients exhibit impairment in working memory and executive function, but not in short- or long-term memory. The impairment of working memory in a patient with COPD may be more due to integrate memory information rather than to memory information storage. COPD patients exhibit a frontal-type cognitive decline.

Sex Differences in the Association Between Pentraxin 3 and Cognitive Decline: The Cardiovascular Health Study

BACKGROUND

The importance of systemic inflammation, measured by C-reactive protein, in cognitive decline has been demonstrated; however, the role of vascular inflammation is less understood. Pentraxin 3 (PTX3) is a novel marker of vascular inflammation.

METHODS

We followed adults 65 and older, free of cardiovascular disease (CVD) for up to 9 years (n = 1,547) in the Cardiovascular Health Study. We evaluated the relationship between PTX3 and change in cognitive function, measured using the Modified Mini-Mental State Examination (3MSE), and incident cognitive impairment (3MSE < 80). Mediation by CVD events, and effect modification by sex and apolipoprotein E ɛ4 allele (APOE4) were also examined.

RESULTS

The average decline in 3MSE was 0.77 points per year. The association between PTX3 and change in 3MSE differed between women and men (p = .02). In the adjusted model, each standard deviation higher in PTX3 was associated with a 0.20 greater decline in 3MSE score per year in women over follow-up (95% CI: -0. 37, -0.03; p = .02), compared to no change in men (β = 0.07; 95% CI: -0.08, 0.22). CVD events had a minor effect on the associations. No effect modification by APOE4 was found, although we observed the association of PTX3 and cognitive impairment in women was attenuated and nonsignificant after adjustment for APOE4. There was a paradoxical protective association between PTX3 and reduced cognitive impairment in men, even after adjustment for APOE4.

CONCLUSIONS

We found that vascular inflammation was significantly associated with cognitive decline in older women, but not men.

Investigating walnut consumption and cognitive trajectories in a representative sample of older US adults

OBJECTIVE

Existing research suggests walnut intake may be associated with better cognitive function in older adults, yet few studies utilise longitudinal data from observational studies of ageing populations. Our objective was to estimate the association between whole walnut intake and cognitive change in a representative sample of older Americans.

DESIGN

Secondary analysis of the Health and Retirement Study and Health Care and Nutrition Study. Walnut consumption was defined as a categorical measure (none, low intake (0·01-0·08 1 oz. servings per day) and moderate intake (>0·08 1 oz. servings per day)) and cognitive function was measured using the Telephone Interview for Cognitive Status. Latent growth modelling estimated the association between walnut consumption and trajectories of cognitive status over a 4-year observational period. Sensitivity analyses assessing non-random dropout and Monte Carlo power analyses were conducted to contextualise results.

SETTING

The USA.

PARTICIPANTS

A sample of 3632 US adults aged 65 years and older.

RESULTS

Those reporting any walnut consumption had greater cognitive scores at baseline than those not consuming walnuts (low walnut consumption, b = 1·53, se = 0·21, P < 0·001; moderate walnut consumption, b = 2·22, se = 0·27, P < 0·001), but walnut consumption was not associated with cognitive change. Walnut consumption was positively associated with socioeconomic status and health behaviours as well as intake of nutrients identified to have neuroprotective benefits.

CONCLUSIONS

We identified an association between walnut consumption and cognitive function in older adults, although we did not find that walnut consumption was protective against age-related cognitive decline.

Current Research on the Impact of Foreign Language Learning Among Healthy Seniors on Their Cognitive Functions From a Positive Psychology Perspective-A Systematic Review

The purpose of this review study is to explore the existing research focusing on the impact of foreign language learning among healthy seniors on their cognitive functions from the positive psychology perspective. The methods are based on a literature review of available sources found on the research topic in two acknowledged databases: Web of Science and Scopus. The search period was not limited by any time period since there are not many studies on this topic. Altogether seven original studies were detected. The findings of this review study thus reveal that foreign language learning (FLL) has a positive impact on the maintenance and/or enhancement of cognitive abilities irrespective of age. In addition, the FLL courses seem to offer new opportunities for healthy seniors in the area of socializing and integration into society, which consequently may positively affect their overall well-being. Furthermore, the research shows that it is partly through the stimulation of social well-being that the cognitive effects of FLL might be observed. Cognitive aspects of older age are to be further investigated, including the importance of learning a foreign language, as basically all research conducted proves at least some maintenance or even improvement of cognitive functions of older people when starting intensive language training.

Longitudinal Maintenance of Cognitive Health in Centenarians in the 100-plus Study

IMPORTANCE

Some individuals who reach ages beyond 100 years in good cognitive health may be resilient against risk factors associated with cognitive decline. Exploring the processes underlying resilience may contribute to the development of therapeutic strategies that help to maintain cognitive health while aging.

OBJECTIVE

To identify individuals who escape cognitive decline until extreme ages and to investigate the prevalence of associated risk factors.

DESIGN, SETTING, AND PARTICIPANTS

The 100-plus Study is a prospective observational cohort study of community-based Dutch centenarians enrolled between 2013 and 2019 who were visited annually until death or until participation was no longer possible. The centenarians self-reported their cognitive health, as confirmed by a proxy. Of the 1023 centenarians approached for study inclusion, 340 fulfilled the study criteria and were included in analyses. Data analysis was performed from April 2019 to December 2019.

MAIN OUTCOMES AND MEASURES

Cognition was assessed using the Mini-Mental State Examination (MMSE). To identify centenarians who escape cognitive decline, this study investigated the association of baseline cognition with survivorship and cognitive trajectories for at least 2 years of follow-up using linear mixed models, adjusted for sex, age, and education. This study investigated the prevalence of apolipoprotein E (APOE) genotypes and cardiovascular disease as risk factors associated with cognitive decline.

RESULTS

At baseline, the median age of 340 centenarians was 100.5 years (range, 100.0-108.2 years); 245 participants (72.1%) were female. The maximum survival estimate plateaued at 82% per year (95% CI, 77% to 87%) across centenarians who scored 26 to 30 points on the baseline MMSE (hazard ratio, 0.56; 95% CI, 0.42 to 0.75; P < .001), suggesting that an MMSE score of 26 or higher is representative of both cognitive and physical health. Among the 79 centenarians who were followed up for 2 years or longer, those with baseline MMSE score less than 26 experienced a decline in MMSE score of 1.68 points per year (95% CI, -2.45 to -0.92 points per year; P = .02), whereas centenarians with MMSE scores of 26 or higher at baseline experienced a decline of 0.71 point per year (95% CI, -1.08 to -0.35 points per year). For 73% of the centenarians with baseline MMSE scores of 26 or higher, no cognitive changes were observed, which often extended to ensuing years or until death. It is estimated that this group is representative of less than 10% of Dutch centenarians. In this group, 18.6% carried at least 1 APOE-ε4 allele, compared with 5.6% of the centenarians with lower and/or declining cognitive performance.

CONCLUSIONS AND RELEVANCE

Most centenarians who scored 26 or higher on the MMSE at baseline maintained high levels of cognitive performance for at least 2 years, in some cases despite the presence of risk factors associated with cognitive decline. Investigation of this group might reveal the processes underlying resilience against risk factors associated with cognitive decline.

Interpreting Subjective and Objective Measures of Job Resources: The Importance of Sociodemographic Context

Salutary retirement policy depends on a clear understanding of factors in the workplace that contribute to work ability at older ages. Research in occupational health typically uses either self-reported or objective ratings of the work environment to assess workplace determinants of health and work ability. This study assessed whether individual characteristics and work-related demands were differentially associated with (1) self-reported ratings of job resources from older workers in the Health and Retirement Study, and (2) corresponding objective ratings of job resources from the Occupational Information Network (O*NET). Results from regression and relative weights analyses showed that self-reported ratings were associated with self-reported job demands and personal resources, whereas corresponding O*NET ratings were associated with differences in gender, race, or socioeconomic standing. As a result, subjective ratings may not capture important aspects of aging workers' sociodemographic background that influence work ability, occupational sorting, opportunities for advancement, and ultimately the job resources available to them. Future studies should consider including both subjective and objective measures to capture individual and societal level processes that drive the relationship between work, health, and aging.

Cognitive Self-Efficacy and Mental Health Ratings after a Memory Skills Group for Older Veterans with PTSD

Objectives: Mental health factors, such as PTSD, can exacerbate typical age-related cognitive changes and lead individuals to have subjective concerns for which few interventions presently exist. This study evaluates self-reported mental health outcomes following a psychoeducational memory skills program designed for veterans over 50 with subjective memory concerns in the context of PTSD. It was hypothesized that outcomes would improve following program participation and that baseline cognitive self-efficacy would moderate improvements in self-reported depression and life satisfaction. Methods: Veterans (n = 101, age ≥ 51) participated in an 8-week memory skills program and completed baseline and post-program assessment data as part of a quality improvement project. Results: Life satisfaction and cognitive self-efficacy demonstrated significant improvement following participation in the memory skills program. Cognitive self-efficacy was found to significantly modify change in depressive symptoms. Conclusions: We found improvement in mental health outcomes following participation in a psychoeducational memory skills program, with differential impact on depressive symptoms for those with low baseline cognitive self-efficacy. Clinical Implications: Participation in this intervention led to improved life satisfaction and cognitive self-efficacy. Cognitive self-efficacy, in turn, appeared to have implications for improving depressive symptomology and may be a useful target of memory skills education.

Egg Consumption, Multi-Domain Cognitive Performance, and Short-Term Cognitive Change in a Representative Sample of Older U.S. Adults

Objective: Existing research supports a positive relationship between egg intake and cognitive function in older populations, although the impact of whole egg consumption on multi-domain cognitive function and cognitive decline in representative samples of older adults has not been described. We examined the association between egg consumption, cognitive performance, and cognitive change in a representative sample of U.S. adults aged 65 and older. Methods: We drew observations from the 2012 and 2014 Health and Retirement Study and the recently released 2013 Health Care and Nutrition Study. The analytic sample contained 3835 respondents, representing a weighted population of 37,806,082 community-dwelling adults aged 65 and older in 2013. Multivariate path analytic models were used to estimate the association between egg consumption groups (none, ≤ 1 serving per week, 2-6 servings per week, ≥ 7 servings per week) and cognitive performance across domains of working memory, executive function, and global mental status. First-order autoregressive models were used to estimate cognitive change over the 2-year observational period. Follow-up analyses examined associations between egg consumption group, dietary patterns, and nutrient intake. Results: On average, older adults consumed 0.34 eggs per day (SD = 0.36). Although bivariate analyses suggested that moderate egg consumers had the best cognitive performance at baseline assessment, egg consumption was not associated with cognitive performance or cognitive change when adjusting models for covariates known to have a robust association with cognitive health. Conclusions: Our results suggest that egg consumption does not benefit, nor is detrimental to, the cognitive health of older adults. Further studies of whole egg consumption and cognitive performance would benefit from controlled experimental settings, longer follow-up periods to measure cognitive change, and assessment of both community-dwelling and institutionalized older adults.

Patients Undergoing Shoulder Stabilization Procedures Do Not Accurately Recall Their Preoperative Symptoms at Short- to Midterm Follow-up

Background:

A patient’s ability to recall symptoms is poor in some elderly populations, but we considered that the recall of younger patients may be more accurate. The accuracy of recall in younger patients after surgery has not been reported to date.

Purpose:

To assess younger patients’ abilities to recall their preoperative symptoms after having undergone shoulder stabilization surgery. We used 2 disease-specific, patient-reported outcome measures (PROMs)—the Western Ontario Shoulder Instability Index (WOSI) and the Melbourne Instability Shoulder Score (MISS)—at a period of up to 2 years postoperatively.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

Participants (N = 119) were stratified into 2 groups: early recall (at 6-8 months postoperatively; n = 58) and late recall (at 9-24 months postoperatively; n = 61). All patients completed the PROMs with instructions to recall preoperative function. The mean and absolute differences between the preoperative scores and recalled scores for each PROM were compared using paired t tests. Correlations between the actual and recalled scores of the subsections for each PROM were calculated using an intraclass correlation coefficient (ICC). The number of individuals who recalled within the minimal detectable change (MDC) of each PROM was calculated.

Results:

Comparison between the means of the actual and recalled preoperative scores for both groups did not demonstrate significant differences (early recall differences, MISS 1.05 and WOSI –38.64; late recall differences, MISS –0.25 and WOSI –24.02). Evaluation of the absolute difference, however, revealed a significant difference between actual and recalled scores for both the late and early groups (early recall absolute differences, MISS 12.26 and WOSI 216.71; late recall absolute differences, MISS 12.84 and WOSI 290.08). Average absolute differences were above the MDC scores of both PROMs at both time points. Subsections of each PROM demonstrated weak to moderate correlations between actual and recalled scores (ICC range, 0.17-0.61). Total scores for the PROMs reached moderate agreement between actual and recalled scores.

Conclusion:

Individual recall after shoulder instability surgery was not accurate. However, the mean recalled PROM scores of each group were not significantly different from the actual scores collected preoperatively, and recall did not deteriorate significantly over 2 years. This suggests that recall of the individual, even in this younger group, cannot be considered accurate for research purposes.

The effects of GSK2981710, a medium-chain triglyceride, on cognitive function in healthy older participants: A randomised, placebo-controlled study

OBJECTIVE

This double-blind, randomised, placebo-controlled, two-part study assessed the impact of GSK2981710, a medium-chain triglyceride (MCT) that liberates ketone bodies, on cognitive function, safety, and tolerability in healthy older adults.

METHODS

Part 1 was a four-period dose-selection study (n = 8 complete). Part 2 was a two-period crossover study (n = 80 complete) assessing the acute (Day 1) and prolonged (Day 15) effects of GSK2981710 on cognition and memory-related neuronal activity. Safety and tolerability of MCT supplementation were monitored in both parts of the study.

RESULTS

The most common adverse event was diarrhoea (100% and 75% of participants in Parts 1 and 2, respectively). Most adverse events were mild to moderate, and 11% participants were withdrawn due to one or more adverse events. Although GSK2981710 (30 g/day) resulted in increased peak plasma β-hydroxybutyrate (BHB) concentrations, no significant improvements in cognitive function or memory-related neuronal activity were observed.

CONCLUSION

Over a duration of 14 days, increasing plasma BHB levels with daily administration of GSK2981710 had no effects on neuronal activity or cognitive function. This result indicates that modulating plasma ketone levels with GSK2981710 may be ineffective in improving cognitive function in healthy older adults, or the lack of observed effect could be related to several factors including study population, plasma BHB concentrations, MCT composition, or treatment duration.

Ventriculoperitoneal Shunt Outcomes of Normal Pressure Hydrocephalus: A Case Series of 116 Patients

Background

Permanent cerebrospinal fluid (CSF) diversion with a ventriculoperitoneal shunt (VPS) is a treatment option for patients with normal pressure hydrocephalus (NPH).

Objectives

Herein, we examine the outcomes, complication rates, and associations between predictors and outcomes after VPS in patients with NPH.

Methods

This was a retrospective review of 116 patients (68 males, 48 females) with NPH who underwent VPS placement from March 2008 to September 2017 after demonstrating objective and/or subjective improvement after a lumbar drain trial. The Chi-square test of independence was used to examine associations between predictors and clinical improvement after shunting. Complications associated with the VPS procedure were recorded.

Results

The mean age was 77 years (range 52-93). The mean duration of disturbance in gait, cognition, and continence were 29, 32, and 28 months, respectively. Of the 116 patients, 111 followed up at two weeks; of these, improvement in gait, incontinence, and cognition were reported in 72, 20, and 23 patients, respectively. Gait improved more than incontinence or cognition. A shorter duration of gait disturbance predicted an improvement in gait after shunting (p<0.01). Being on a cognition-enhancing medication predicted an improvement in cognition and/or incontinence after shunting (p<0.05). Complications included misplaced proximal catheters (n=6), asymptomatic catheter tract hemorrhages (n=3), bilateral hygromas (n=7), subdural hematomas (SDH) (n=5), and CSF leak (n=1).

Conclusion

VPS placement in patients with NPH is well-tolerated and associated with improved outcomes at least in the short-term follow-up (<6 months). A shorter duration of gait disturbance and being on a cognition-enhancing medication are associated with greater improvement after VPS.

Avaliação do Programa de Treinamento para Memória de Trabalho em Idosos

RESUMO Objetivo Verificar os benefícios do Treinamento de Memória de Trabalho em DVD para idosos. Método Participaram do estudo 16 voluntários com idade superior a 60 anos (média etária de 67,43 anos) sem queixas de perda auditiva, problemas neurológicos ou psiquiátricos, avaliados inicialmente com o MEEM e posteriormente com a avaliação específica para memória de trabalho. Em seguida, os quatro participantes que não tinham disponibilidade para comparecer à Universidade formaram o grupo controle e os doze restantes foram incluídos no grupo experimental. O grupo experimental foi exposto aos três DVDs que compõem o primeiro conjunto de exercícios e reavaliado com o teste específico para memória de trabalho em intervalos regulares. O grupo controle também foi submetido às reavaliações nos mesmos períodos do grupo experimental. Resultados Enquanto o grupo controle não apresentou qualquer alteração nas avaliações, o desempenho no teste de memória do grupo experimental melhorou significativamente após a apresentação dos DVDs. Além disso, o grupo experimental relatou os benefícios do treinamento para suas atividades cotidianas. Conclusão O estudo demonstra os benefícios do Treinamento de Memória de Trabalho em DVD para idosos, que se revela uma ferramenta promissora para novos estudos longitudinais com populações maiores.

Animal models of cognitive aging and circuit-specific vulnerability

Medial temporal lobe and prefrontal cortical structures are particularly vulnerable to dysfunction in advanced age and neurodegenerative diseases. This review focuses on cognitive aging studies in animals to illustrate the important aspects of the animal model paradigm for investigation of age-related memory and executive function loss. Particular attention is paid to the discussion of the face, construct, and predictive validity of animal models for determining the possible mechanisms of regional vulnerability in aging and for identifying novel therapeutic strategies. Aging is associated with a host of regionally specific neurobiologic alterations. Thus, targeted interventions that restore normal activity in one brain region may exacerbate aberrant activity in another, hindering the restoration of function at the behavioral level. As such, interventions that target the optimization of "cognitive networks" rather than discrete brain regions may be more effective for improving functional outcomes in the elderly.

The 12-Word Philadelphia Verbal Learning Test Performances in Older Adults: Brain MRI and Cerebrospinal Fluid Correlates and Regression-Based Normative Data

Background/Aims

This study evaluated neuroimaging and biological correlates, psychometric properties, and regression-based normative data of the 12-word Philadelphia Verbal Learning Test (PVLT), a list-learning test.

Methods

Vanderbilt Memory and Aging Project participants free of clinical dementia and stroke (n = 230, aged 73 ± 7 years) completed a neuropsychological protocol and brain MRI. A subset (n = 111) underwent lumbar puncture for analysis of Alzheimer's disease (AD) and axonal integrity cerebrospinal fluid (CSF) biomarkers. Regression models related PVLT indices to MRI and CSF biomarkers adjusting for age, sex, race/ethnicity, education, APOE-ε4 carrier status, cognitive status, and intracranial volume (MRI models). Secondary analyses were restricted to participants with normal cognition (NC; n = 127), from which regression-based normative data were generated.

Results

Lower PVLT performances were associated with smaller medial temporal lobe volumes (p < 0.05) and higher CSF tau concentrations (p < 0.04). Among NC, PVLT indices were associated with white matter hyperintensities on MRI and an axonal injury biomarker (CSF neurofilament light; p < 0.03).

Conclusion

The PVLT appears sensitive to markers of neurodegeneration, including temporal regions affected by AD. Conversely, in cognitively normal older adults, PVLT performance seems to relate to white matter disease and axonal injury, perhaps reflecting non-AD pathways to cognitive change. Enhanced normative data enrich the clinical utility of this tool.

Genetic effects and gene-by-education interactions on episodic memory performance and decline in an aging population

Both social and genetic factors contribute to cognitive impairment and decline, yet genetic factors identified through genome-wide association studies (GWAS) explain only a small portion of trait variability. This "missing heritability" may be due to rare, potentially functional, genetic variants not assessed by GWAS, as well as gene-by-social factor interactions not explicitly modeled. Gene-by-social factor interactions may also operate differently across race/ethnic groups. We selected 39 genes that had significant, replicated associations with cognition, dementia, and related traits in published GWAS. Using gene-based analysis (SKAT/iSKAT), we tested whether common and/or rare variants were associated with episodic memory performance and decline either alone or through interaction with education in >10,000 European ancestry (EA) and >2200 African ancestry (AA) respondents from the Health and Retirement Study (HRS). Nine genes in EA and five genes in AA were associated with memory performance or decline (p < 0.05), and these effects did not attenuate after adjusting for education. Interaction between education and CLPTM1 on memory performance was significant in AA (p = 0.003; FDR-adjusted p = 0.038) and nominally significant in EA (p = 0.026). In both ethnicities, low memory performance was associated with CLPTM1 genotype (rs10416261) only for those with less than high school education, and effects persisted after adjusting for APOE ε4. For over 70% of gene-by-education interactions across the genome that were at least nominally significant in either ethnic group (p < 0.05), genetic effects were only observed for those with less than high school education. These results suggest that genetic effects on memory identified in this study are not mediated by education, but there may be important gene-by-education interactions across the genome, including in the broader APOE genomic region, which operate independently of APOE ε4. This work illustrates the importance of developing theoretical frameworks and methodological approaches for integrating social and genomic data to study cognition across ethnic groups.

Performance Level and Cortical Atrophy Modulate the Neural Response to Increasing Working Memory Load in Younger and Older Adults

There is evidence that the neural response to increasing working memory (WM) load is modulated by age and performance level. For a valid interpretation of these effects, however, it is important to understand, whether and how they are related to gray matter atrophy. In the current work, we therefore used functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM) to examine the association between age, performance level, spatial WM load-related brain activation and gray matter volume in 18 younger high-performers (YHP), 17 younger low-performers (YLP), 17 older high-performers (OHP), and 18 older low-performers (OLP). In multiple sub regions of the prefrontal cortex (PFC), load-related activation followed a linear trend with increasing activation at increasing load in all experimental groups. Results did not reveal differences between the sub groups. Older adults additionally showed a pattern of increasing activation from low to medium load but stable or even decreasing activation from medium to high load in other sub regions of the PFC (quadratic trend). Quadratic trend related brain activation was higher in older than in younger adults and in OLP compared to OHP. In OLP, quadratic trend related brain activation was negatively correlated with both performance accuracy and prefrontal gray matter volume. The results suggest an efficient upregulation of multiple PFC areas as response to increasing WM load in younger and older adults. Older adults and particularly OLP additionally show dysfunctional response patterns (i.e., enhanced quadratic trend related brain activation compared to younger adults and OHP, respectively) in other PFC clusters being associated with gray matter atrophy.

Structural racism in the workplace: Does perception matter for health inequalities?

Structural racism has been linked to racial health inequalities and may operate through an unequal labor market that results in inequalities in psychosocial workplace environments (PWE). Experiences of the PWE may be a critical but understudied source of racial health disparities as most adults spend a large portion of their lives in the workplace, and work-related stress affects health outcomes. Further, it is not clear if the objective characteristics of the workplace are important for health inequalities or if these inequalities are driven by the perception of the workplace. Using data from the 2008 to 2012 waves of the Health and Retirement Study (HRS), a probability-based sample of US adults 50 years of age and older and the Department of Labor's Occupational Information Network (O*NET), we examine the role of both standardized, objective (O*NET) and survey-based, subjective (as in HRS) measures of PWEs on health and Black-White health inequalities. We find that Blacks experience more stressful PWEs and have poorer health as measured by self-rated health, episodic memory function, and mean arterial pressure. Mediation analyses suggest that these objective O*NET ratings, but not the subjective perceptions, partially explain the relationship between race and health. We discuss these results within the extant literature on workplace and health and health inequalities. Furthermore, we discuss the use of standardized objective measures of the PWE to capture racial inequalities in workplace environment.

Alterations in Hippocampal Activity and Alzheimer's Disease

The aging population and those with amnestic mild cognitive impairment (aMCI) are at increased risk for developing Alzheimer's disease (AD). Individuals with aMCI in particular may display pathological changes in brain function that may ultimately result in a diagnosis of AD. This review focuses specifically on hippocampal hyperexcitability, a pathology that is sometimes detectable years before diagnosis, which has been observed in individuals with aMCI. We describe how changes in hippocampal activity are associated with, or in some cases may be permissive for, the development of AD. Finally, we describe how lifestyle changes, including exercise and dietary changes can attenuate cognitive decline and hippocampal hyperexcitability, potentially reducing the risk of developing AD.

Recent cancer treatment and memory decline in older adults: An analysis of the 2002-2012 Health and Retirement Study

OBJECTIVE

Few studies have examined the impact of cancer treatment on cognitive trajectories in the growing population of older adults diagnosed with and surviving cancer. This study examined whether recent cancer and its treatment accelerated memory decline in older adults.

MATERIALS AND METHODS

We conducted a secondary analysis of observations drawn from the Health and Retirement Study (2002-2012), a population-based sample of older adults in the United States. Changes in immediate (IWR) and delayed word recall (DWR) scores were estimated by latent growth modeling in individuals who never had cancer (n=10,939) or had been diagnosed with cancer between 2000 and 2002 and received treatment with some combination of radiation and/or surgery (n=240), chemotherapy only (n=34), or chemotherapy and some combination of radiation and/or surgery (n=64).

RESULTS

In the period immediately following treatment, individuals reporting a recent cancer treated with chemotherapy and surgery/radiation experienced significantly more rapid decline in IWR (b =-0.34, SE =0.17, p=0.047) and DWR (b=-0.38, SE=0.19, p=0.049) than the non-cancer group. Sensitivity analyses addressing mortality selection and memory-related disease at baseline attenuated the strength of these associations. There were no other statistically significant differences in estimated linear or quadratic slope by cancer status or treatment.

CONCLUSION

Our results support a potential association between recent cancer treatment and trajectories of memory decline in older adults and provide guidance on the interpretation of statistical estimates from panel studies of health and aging.

Smart Homes for Elderly Healthcare-Recent Advances and Research Challenges

Advancements in medical science and technology, medicine and public health coupled with increased consciousness about nutrition and environmental and personal hygiene have paved the way for the dramatic increase in life expectancy globally in the past several decades. However, increased life expectancy has given rise to an increasing aging population, thus jeopardizing the socio-economic structure of many countries in terms of costs associated with elderly healthcare and wellbeing. In order to cope with the growing need for elderly healthcare services, it is essential to develop affordable, unobtrusive and easy-to-use healthcare solutions. Smart homes, which incorporate environmental and wearable medical sensors, actuators, and modern communication and information technologies, can enable continuous and remote monitoring of elderly health and wellbeing at a low cost. Smart homes may allow the elderly to stay in their comfortable home environments instead of expensive and limited healthcare facilities. Healthcare personnel can also keep track of the overall health condition of the elderly in real-time and provide feedback and support from distant facilities. In this paper, we have presented a comprehensive review on the state-of-the-art research and development in smart home based remote healthcare technologies.

Tau and β-Amyloid Are Associated with Medial Temporal Lobe Structure, Function, and Memory Encoding in Normal Aging

Normal aging is associated with a decline in episodic memory and also with aggregation of the β-amyloid (Aβ) and tau proteins and atrophy of medial temporal lobe (MTL) structures crucial to memory formation. Although some evidence suggests that Aβ is associated with aberrant neural activity, the relationships among these two aggregated proteins, neural function, and brain structure are poorly understood. Using in vivo human Aβ and tau imaging, we demonstrate that increased Aβ and tau are both associated with aberrant fMRI activity in the MTL during memory encoding in cognitively normal older adults. This pathological neural activity was in turn associated with worse memory performance and atrophy within the MTL. A mediation analysis revealed that the relationship with regional atrophy was explained by MTL tau. These findings broaden the concept of cognitive aging to include evidence of Alzheimer's disease-related protein aggregation as an underlying mechanism of age-related memory impairment.SIGNIFICANCE STATEMENT Alterations in episodic memory and the accumulation of Alzheimer's pathology are common in cognitively normal older adults. However, evidence of pathological effects on episodic memory has largely been limited to β-amyloid (Aβ). Because Aβ and tau often cooccur in older adults, previous research offers an incomplete understanding of the relationship between pathology and episodic memory. With the recent development of in vivo tau PET radiotracers, we show that Aβ and tau are associated with different aspects of memory encoding, leading to aberrant neural activity that is behaviorally detrimental. In addition, our results provide evidence linking Aβ- and tau-associated neural dysfunction to brain atrophy.

Innervation from the entorhinal cortex to the dentate gyrus and the vulnerability to Zn2

Hippocampal Zn²⁺ homeostasis is critical for cognitive activity and hippocampus-dependent memory. Extracellular Zn²⁺ signaling is linked to extracellular glutamate signaling and leads to intracellular Zn²⁺ signaling, which is involved in cognitive activity. On the other hand, excess intracellular Zn²⁺ signaling that is induced by excess glutamate signaling is involved in cognitive decline. In the hippocampal formation, the dentate gyrus is the most vulnerable to aging and is thought to contribute to age-related cognitive decline. The layer II of the entorhinal cortex is the most vulnerable to neuronal death in Alzheimer's disease. The perforant pathway provides input from the layer II to the dentate gyrus and is one of the earliest affected pathways in Alzheimer's disease. Medial perforant pathway-dentate granule cell synapses are vulnerable to either excess intracellular Zn²⁺ or β-amyloid (Aβ)-bound zinc, which induce transient cognitive decline via attenuation of medial perforant pathway LTP. However, it is unknown whether the vulnerability to excess intracellular Zn²⁺ is involved in region-specific vulnerability to aging and Alzheimer's disease. To discover a strategy to prevent short-term cognitive decline in normal aging process and the pre-dementia stage of Alzheimer's disease, the present paper deals with vulnerability of medial perforant pathway-dentate granule cell synapses to intracellular Zn²⁺ dyshomeostasis and its possible involvement in differential vulnerability to aging and Alzheimer's disease in the hippocampal formation.

Self-reported severe memory problems as a screen for cognitive impairment and dementia

Undetected cognitive impairment (CI) and dementia are important clinical and epidemiological problems. This study addresses the effectiveness of using a single self-reported measure of severe memory problems (SMP) as a screen for CI and dementia. For the purposes of the study, 3220 elderly women participated in a mailed Health Survey Questionnaire and telephone interviews. Cognitive scores derived from the Telephone Interview for Cognitive Status–modified (TICSm) were calculated. Based on a multi-stage assessment strategy, all subjects were classified in one of three status categories: dementia, CI, or unimpaired. The SMP question was suggestive of cognitive problems in the majority of responders. t-tests found affirmative responders scored much lower on the cognitive test than negative responders. The SMP question had a sensitivity of .24 and a specificity of .99 for screening CI and dementia. While other assessment measures are needed, the SMP question is highly suggestive of CI and may serve as a first-stage screen in clinical and research settings.

Estimating the Co-Development of Cognitive Decline and Physical Mobility Limitations in Older U.S. Adults

This study examines the co-development of cognitive and physical function in older Americans using an age-heterogeneous sample drawn from the Health and Retirement Study (1998–2008). We used multiple-group parallel process latent growth models to estimate the association between trajectories of cognitive function as measured by immediate word recall scores, and limitations in physical function as measured as an index of functional mobility limitations. Nested model fit testing was used to assess model fit for the separate trajectories followed by estimation of an unconditional parallel process model. Controls for demographic characteristics, socioeconomic status, and chronic health conditions were added to the best-fitting parallel process model. Pattern mixture models were used to assess the sensitivity of the parameter estimates to the effect of selective attrition. Results indicated that favorable cognitive health and mobility at initial measurement were associated with faster decline in the alternate functional domain. The cross-process associations remained significant when we adjusted estimates for the influence of covariates and selective attrition. Demographic and socioeconomic characteristics were consistently associated with initial cognitive and physical health but had few relations with change in these measures.

Socioeconomic Status Across the Life Course and Cognitive Function Among Older Adults: An Examination of the Latency, Pathways, and Accumulation Hypotheses

OBJECTIVE

This study investigated the relationship between life course socioeconomic status (SES) and cognitive function among older adults in the United States over a 12-year observation period. The mediation of adult SES on the association between childhood SES and cognition was examined, along with the relationship between cumulative SES and cognition.

METHOD

Using a nationally representative sample from the Health and Retirement Study, cognitive status and change in cognition from 1998 to 2010 were examined using growth curve models.

RESULTS

The results showed that cognitive function varied within-persons and between-persons. SES disadvantage in childhood was associated with lower cognitive function at baseline. Adult SES mediated the relationship between childhood SES and cognitive function. Persons with higher cumulative SES demonstrated an advantage in cognitive function.

DISCUSSION

Childhood SES and adult SES both had relationships with cognitive status and, to a lesser degree, change in cognition in later life.

Hypoglycemia-associated changes in the electroencephalogram in patients with type 1 diabetes and normal hypoglycemia awareness or unawareness

Hypoglycemia is associated with increased activity in the low-frequency bands in the electroencephalogram (EEG). We investigated whether hypoglycemia awareness and unawareness are associated with different hypoglycemia-associated EEG changes in patients with type 1 diabetes. Twenty-four patients participated in the study: 10 with normal hypoglycemia awareness and 14 with hypoglycemia unawareness. The patients were studied at normoglycemia (5-6 mmol/L) and hypoglycemia (2.0-2.5 mmol/L), and during recovery (5-6 mmol/L) by hyperinsulinemic glucose clamp. During each 1-h period, EEG, cognitive function, and hypoglycemia symptom scores were recorded, and the counterregulatory hormonal response was measured. Quantitative EEG analysis showed that the absolute amplitude of the θ band and α-θ band up to doubled during hypoglycemia with no difference between the two groups. In the recovery period, the θ amplitude remained increased. Cognitive function declined equally during hypoglycemia in both groups and during recovery reaction time was still prolonged in a subset of tests. The aware group reported higher hypoglycemia symptom scores and had higher epinephrine and cortisol responses compared with the unaware group. In patients with type 1 diabetes, EEG changes and cognitive performance during hypoglycemia are not affected by awareness status during a single insulin-induced episode with hypoglycemia.

Docosahexaenoic acid and adult memory: a systematic review and meta-analysis

Introduction

Subjective memory complaints are common with aging. Docosahexaenoic acid (DHA; 22:6 n-3) is a long-chain polyunsaturated fatty acid (LCPUFA) and an integral part of neural membrane phospholipids that impacts brain structure and function. Past research demonstrates a positive association between DHA plasma status/dietary intake and cognitive function.

Objectives

The current meta-analysis was designed to determine the effect of DHA intake, alone or combined with eicosapentaenoic acid (EPA; 20:5 n-3), on specific memory domains: episodic, working, and semantic in healthy adults aged 18 years and older. A secondary objective was to systematically review/summarize the related observational epidemiologic literature.

Methods

A systematic literature search of clinical trials and observational studies that examined the relationship between n-3 LCPUFA on memory outcomes in healthy adults was conducted in Ovid MEDLINE and EMBASE databases. Studies of subjects free of neurologic disease at baseline, with or without mild memory complaints (MMC), were included. Random effects meta-analyses were conducted to generate weighted group mean differences, standardized weighted group mean differences (Hedge’s g), z-scores, and p-values for heterogeneity comparing DHA/EPA to a placebo. A priori sub-group analyses were conducted to evaluate the effect of age at enrollment, dose level, and memory type tested.

Results

Episodic memory outcomes of adults with MMC were significantly (P<.004) improved with DHA/EPA supplementation. Regardless of cognitive status at baseline, > 1 g/day DHA/EPA improved episodic memory (P<.04). Semantic and working memory changes from baseline were significant with DHA but no between group differences were detected. Observational studies support a beneficial association between intake/blood levels of DHA/EPA and memory function in older adults.

Conclusion

DHA, alone or combined with EPA, contributes to improved memory function in older adults with mild memory complaints.

Enhancing dentate gyrus function with dietary flavanols improves cognition in older adults

The dentate gyrus (DG) is a region in the hippocampal formation whose function declines in association with human aging and is therefore considered to be a possible source of age-related memory decline. Causal evidence is needed, however, to show that DG-associated memory decline in otherwise healthy elders can be improved by interventions that enhance DG function. We addressed this issue by first using a high-resolution variant of functional magnetic resonance imaging (fMRI) to map the precise site of age-related DG dysfunction and to develop a cognitive task whose function localized to this anatomical site. Then, in a controlled randomized trial, we applied these tools to study healthy 50-69-year-old subjects who consumed either a high or low cocoa flavanol-containing diet for 3 months. A high-flavanol intervention was found to enhance DG function, as measured by fMRI and by cognitive testing. Our findings establish that DG dysfunction is a driver of age-related cognitive decline and suggest non-pharmacological means for its amelioration.

Genetic variants in a 'cAMP element binding protein' (CREB)-dependent histone acetylation pathway influence memory performance in cognitively healthy elderly individuals

The molecular pathways underlying age-related memory changes remain unclear. There is a substantial genetic contribution to memory performance through life span. A recent study has implicated RbAp48, which mediates its effect on age-related memory decline by interacting with cyclic adenosine monophosphate responsive element binding protein (CREB)1 binding protein and influencing this histone acetylation pathway. To validate these findings, we tested whether genetic variants in RbAp48, CREB1, and CREBBP are associated with memory performance in 3 independent data sets consisting of 2674 cognitively healthy elderly individuals. Genetic variant rs2526690 in the CREBBP gene was significantly associated with episodic memory performance (pmeta = 3.7 × 10(-4)) in a multivariate model adjusted for age, sex, and apolipoprotein E status. Identifying genetic variants that modulate mechanisms of cognitive aging will allow identifying valid targets for therapeutic intervention.

Lexical retrieval in discourse: an early indicator of Alzheimer's dementia

We examined the progression of lexical-retrieval deficits in individuals with neuropathologically determined Alzheimer's disease (AD; n = 23) and a comparison group without criteria for AD (n = 24) to determine whether linguistic changes were a significant marker of the disease. Our participants underwent multiple administrations of a neuropsychological battery, with initial administration occurring on average 16 years prior to death. The battery included the Boston Naming Test (BNT), a letter fluency task (FAS) and written description of the Cookie Theft Picture (CTP). Repeated measures analysis revealed that the AD-group showed progressively greater decline in FAS and CTP lexical performance than the comparison group. Cross-sectional time-specific group comparisons indicated that the CTP differentiated performance between the two groups at 7-9 years prior to death and FAS and BNT only at 2-4 years. These results suggest that lexical-retrieval deficits in written discourse serve as an early indicator of AD.

Perturbations of neural circuitry in aging, mild cognitive impairment, and Alzheimer's disease

Alzheimer's disease (AD) is a global public health threat that continues to rise as the proportion of the population over the age of 60 rapidly increases. Aging and dementia are both associated with cognitive decline and share some features in terms of structural and functional alterations in neural circuitry. In this review, we attempt to highlight the network perturbations that occur in "typical" aging and emphasize how they may differ from those that manifest in dementia. We focus in particular on neuroimaging studies of the medial temporal lobe (MTL) network, which is involved in episodic memory and is known to change both with age and with AD pathology. We propose a temporal model of structural and functional alterations in the MTL along the aging-dementia continuum. The earliest changes are synaptic in nature and are detectable in particularly vulnerable white matter pathways such as the perforant path. These are followed by structural degradation in the transentorhinal region and subsequently neurodegeneration of the hippocampus as a result of accumulating pathology as well as deafferentation from entorhinal input. We believe that testing this model explicitly is an important direction for future research, particularly in the context of biomarker discovery and clinical trial design.

The role of lifestyle behaviors on 20-year cognitive decline

This study examined the association between smoking, physical activity and dietary choice at 36 and 43 years, and change in these lifestyle behaviors between these ages, and decline in verbal memory and visual search speed between 43 and 60-64 years in 1018 participants from MRC National Survey of Health and Development (NSHD, the British 1946 birth cohort). ANCOVA models were adjusted for sex, social class of origin, childhood cognition, educational attainment, adult social class, and depression; then the lifestyle behaviors were additionally mutually adjusted. Results showed that healthy dietary choice and physical activity were associated, respectively, with slower memory and visual search speed decline over 20 years, with evidence that increasing physical activity was important. Adopting positive health behaviors from early midlife may be beneficial in reducing the rate of cognitive decline and ultimately reducing the risk of dementia.

Accuracy of prospective memory tests in mild Alzheimer's disease

OBJECTIVES: To verify the accuracy of prospective memory (ProM) tests in Alzheimer's disease (AD). METHODS: Twenty mild AD patients (CDR 1), and 20 controls underwent Digit Span (DS), Trail Making (TM) A and B, visual perception, Rey Auditory-Verbal Learning tests, and Cornell Scale for Depression. AD diagnosis was based on DSM-IV and NINCDS-ADRDA criteria. ProM was assessed with the appointment and belonging subtests of Rivermead Behavioral Memory Test (RBMT); and with two new tests (the clock and animal tests). RESULTS: AD patients had a worse performance than controls on the majority of tests, except DS forward and TM-A. There was no correlation between RBMT and the new ProM tests. As for accuracy, the only significant difference concerned the higher sensitivity of our animal test versus the RBMT belonging test. CONCLUSIONS: The clock and the animal tests showed similar specificity, but higher sensitivity than the RBMT subtests.

Visual memories for perceived length are well preserved in older adults

Three experiments compared younger (mean age was 23.7years) and older (mean age was 72.1years) observers' ability to visually discriminate line length using both explicit and implicit standard stimuli. In Experiment 1, the method of constant stimuli (with an explicit standard) was used to determine difference thresholds, whereas the method of single stimuli (where the knowledge of the standard length was only implicit and learned from previous test stimuli) was used in Experiments 2 and 3. The study evaluated whether increases in age affect older observers' ability to learn, retain, and utilize effective implicit visual standards. Overall, the observers' length difference thresholds were 5.85% of the standard when the method of constant stimuli was used and improved to 4.39% of the standard for the method of single stimuli (a decrease of 25%). Both age groups performed similarly in all conditions. The results demonstrate that older observers retain the ability to create, remember, and utilize effective implicit standards from a series of visual stimuli.

Aging alters the expression of genes for neuroprotection and synaptic function following acute estradiol treatment

This study used microarray analysis to examine age-related changes in gene expression 6 and 12 h following a single estradiol injection in ovariectomized mice. Estradiol-responsive gene expression at the 6 h time point was reduced in aged (18 months) animals compared with young (4 months) and middle-aged (MA, 12 months) mice. Examination of gene clustering within biological and functional pathways indicated that young and MA mice exhibited increased expression of genes for cellular components of the synapse and decreased expression of genes related to oxidative phosphorylation and mitochondrial dysfunction. At the 12 h time point, estradiol-responsive gene expression increased in aged animals and decreased in young and MA mice compared with the 6 h time point. Gene clustering analysis indicated that aged mice exhibited increased expression of genes for signaling pathways that are rapidly influenced by estradiol. The age differences in gene expression for rapid signaling pathways may relate to disparity in basal pathway activity and estradiol mediated activation of rapid signaling cascades.

Memory score discrepancies by healthy middle-aged and older individuals: the contributions of age and education

The aim of this study was to examine discrepancies between immediate/delayed recall and recall/working memory in middle-aged and older persons by age and education. Participants were 322 healthy individuals from the community who were stratified into three age and three education groups. Immediate and delayed recall distributions of WMS-III Logical Memory (LM) scores approximated normal curves, and LM savings scores showed a significant, but small, effect of age. LM (immediate, delayed) and Letter-Number Sequencing (LNS) discrepancies varied as a function of age and education. The difference between LM and LNS was not significant in the younger and less educated participants, but increased with age in the most educated group, and in the oldest group LNS exceeded LM (immediate and delayed). The results indicate deterioration in encoding and retrieval, rather than storage, with age, and show a differential, but small, effect of age and education on the memory measures. Working memory was resistant to age-related decline relative to immediate and delayed recall in the oldest, most educated group. Delayed recall-working memory discrepancy is relatively stable with age and education and may be a useful index of the onset of memory pathology across different ages and levels of education.