Cohort differences in cognitive aging and terminal decline in the Seattle Longitudinal Study

The trends of mental disorders mortality in China over a 33-year period

OBJECTIVES

We investigated the variations in the trends of mental disorders mortality by age, period, and cohort, over a 33-year period from 1987 to 2020, to reveal the relationship between age, period, cohort, and mental disorders mortality, as well as providing guidance for resource allocation to prevent mental disorders-related deaths in vulnerable target populations.

METHODS

The data of mental disorders mortality 1987-2020 were from five administrative organizations, which collected from the National Health Commission in China with national monitoring by sex and age, covering 31 provinces in China. The International Classification of Diseases (ICD), its 9th Revision (ICD-9) and its 10th Revision were used to code the mental diseases. From 1987-2002, ICD-9 was used, and ICD-10 was used from 2003 to 2020. The age standardized mortality rates (ASMRs) were calculated using the World Standard Population as the reference. We used joinpoint models to assess the trends of mental disorders mortality in China for the period 1987-2020. And the age-period-cohort models were employed to estimate the age-period-cohort effect on mental disorders mortality.

RESULTS

The age-standardized overall mental disorders mortality rate (ASMR) showed a downward trend from 1987 to 2020. Further, the ASMR of individuals in urban was higher than that in rural from 1987 to 2001, but, post-2002, this urban-rural disparity in ASMR showed a less clear pattern, with urban areas occasionally surpassing rural areas and vice versa. ASMR is less prevalent among females compared to males overall. The contribution of age effects to mental disorders mortality gradually increases with advancing age, the period effects of mental disorders mortality gradually decrease over time. The cohort effect's contribution to mental disorders mortality decreases in the newly born population, while in the older birth cohorts, the cohort effect's contribution to the mortality rate of mental disorders increases.

CONCLUSIONS

The ASMR exhibits a decreasing trend from 1987 to 2020, and these change trend showed urban-rural and sex differences. The primary factors contributing to this overall decline are period effects and cohort effects. Our results provide valuable information for shaping mental health policies, designing targeted interventions, and preparing for future changes in disease mortality rates. The focus on different demographic factors allows for a nuanced and tailored approach to mental health promotion and intervention strategies.

An Early and Unequal Decline: Life Course Trajectories of Cognitive Aging in the United States

Objectives: Cognitive aging is a lifelong process with implications for Alzheimer's disease and dementia. This study aims to fill major gaps in research on the natural history of and social disparities in aging-related cognitive decline over the life span. Methods: We conducted integrative data analysis of four large U.S. population-based longitudinal studies of individuals aged 12 to 105 followed over two decades and modeled age trajectories of cognitive function in multiple domains. Results: We found evidence for the onset of cognitive decline in the 4th decade of life, varying gender differences with age, and persistent disadvantage among non-Hispanic Blacks, Hispanics, and those without college education. We further found improvement in cognitive function across 20th century birth cohorts but widening social inequalities in more recent cohorts. Discussion: These findings advance an understanding of early life origins of dementia risk and invite future research on strategies for promoting cognitive health for all Americans.

New evidence of trends in cognitive function among middle-aged and older adults in China, 2011-2018: an age-period-cohort analysis

BACKGROUND

Increasing evidence from high-income countries suggests the risk of cognitive impairment has been declining recently. However, related studies in China have rarely been done, and the results are inconsistent. We analyze the trends in cognitive function among middle-aged and older adults in China between 2011 and 2018.

METHODS

We used data from four waves of the China Health and Retirement Longitudinal Study (CHARLS), including 48918 individuals aged 45 years and older. Cognitive function was assessed using the CHARLS cognitive measures containing episodic memory, orientation, attention, and visuospatial abilities. The hierarchical age-period-cohort (APC) model was used to quantify the separate age, period, and cohort effects on trends in cognitive function.

RESULTS

The study sample's ages ranged from 45 to 105 years (Mean = 59.2, SD = 9.4). Cognitive function declined with age net of period and cohort effects, an apparent acceleration in the rate of cognitive decline after age 65 was found adjusting for individual characteristics. Although period effects on trends in cognitive function remained stable during the study period, hierarchical APC models demonstrated significant cohort variations. Independent of age and period effects, there was a fluctuating trend across cohorts before 1960 and an overall decline across successive cohorts.

CONCLUSIONS

Our study indicates that the age effect remains the most crucial factor regarding cognitive decline. Moreover, results demonstrate that cohorts living in social upheaval leading to educational deprivation and/or nutritional deficiency in early life may face a higher risk for cognitive deterioration later in life. Such findings indicate that dementia prevention from a life course perspective and cohort-specific strategies are critical to alleviating the future public-health burdens related to cognitive aging. Ongoing attention should be paid to the role of cross-cohort differences in education on cohort trends in cognition in countries like China that are aging rapidly and have a late start in educational expansion compared to other countries. Other factors, such as environmental stimulation, need to be noticed in younger cohorts.

Younger Than Ever? Subjective Age Is Becoming Younger and Remains More Stable in Middle-Age and Older Adults Today

Little is known about historical shifts in subjective age (i.e., how old individuals feel). Moving beyond the very few time-lagged cross-sectional cohort comparisons, we examined historical shifts in within-person trajectories of subjective age from midlife to advanced old age. We used cohort-comparative longitudinal data from middle-age and older adults in the German Ageing Survey (N = 14,928; ~50% female) who lived in Germany and were between 40 and 85 years old when entering the study. They provided up to seven observations over 24 years. Results revealed that being born later in historical time is associated with feeling younger by 2% every birth-year decade and with less intraindividual change toward an older subjective age. Women reported feeling younger than men; this gender gap widened across cohorts. The association of higher education with younger subjective age became weaker across cohorts. Potential reasons for the subjective-rejuvenation effect across cohorts are discussed.

No Appreciable Effect of Education on Aging-Associated Declines in Cognition: A 20-Year Follow-Up Study

Education has been claimed to reduce aging-associated declines in cognitive function. Given its societal relevance, considerable resources have been devoted to this research. However, because of the difficulty of detecting modest rates of change, findings have been mixed. These discrepancies may stem from methodological shortcomings such as short time spans, few waves, and small samples. The present study overcame these limitations (N = 1,892, nine waves over a period of 20 years). We tested the effect of education level on baseline performance (intercept) and the rate of change (slope) in crystallized and fluid cognitive abilities (gc and gf, respectively) in a sample of Japanese adults. Albeit positively related to both intercepts, education had no impact on either the gc or the gf slope. Furthermore, neither intercept exhibited any appreciable correlation with either slope. These results thus suggest that education has no substantial role (direct or mediated) in aging-related changes in cognition.

Erectile Function, Sexual Satisfaction, and Cognitive Decline in Men From Midlife to Older Adulthood

BACKGROUND AND OBJECTIVES

Vascular theories of cognitive aging have focused on macrovascular changes and cognitive decline. However, according to the artery-size hypothesis, microvascular changes, such as those that underlie changes in erectile function, may also play an important role in contributing to cognitive decline. Thus, we examined associations between erectile function, sexual satisfaction, and cognition starting in middle age because this represents a transition period where declines in these areas emerge.

RESEARCH DESIGN AND METHODS

We examined 818 men from the Vietnam Era Twin Study of Aging across three waves at mean ages 56, 61, and 68. Erectile function and sexual satisfaction were measured using the International Index of Erectile Function. Cognitive performance was measured using factor scores for episodic memory, executive function, and processing speed. We tested multilevel models hierarchically, adjusting for demographics, frequency of sexual activity, and physical and mental health confounders to examine how changes in erectile function and sexual satisfaction related to changes in cognitive performance.

RESULTS

Lower erectile function at baseline was related to poorer performance in all cognitive domains at baseline and faster declines in processing speed over time. However, baseline sexual satisfaction was unrelated to cognitive performance. Decreases in erectile function and sexual satisfaction were both associated with memory decline.

DISCUSSION AND IMPLICATIONS

Decreasing sexual health may signal an increased risk for cognitive decline. We discuss potential mechanisms, including microvascular changes and psychological distress. Discussing and tracking sexual health in middle-aged men may help to identify those likely to face memory decline.

The Influence of Birth Cohorts on Future Cognitive Decline

BACKGROUND

Slowed rates of cognitive decline have been reported in individuals with higher cognitive reserve (CR), but interindividual discrepancies remain unexplained. Few studies have reported a birth cohort effect, favoring later-born individuals, but these studies remain scarce.

OBJECTIVE

We aimed to predict cognitive decline in older adults using birth cohorts and CR.

METHODS

Within the Alzheimer's Disease Neuroimaging Initiative, 1,041 dementia-free participants were assessed on four cognitive domains (verbal episodic memory; language and semantic memory; attention; executive functions) at each follow-up visit up to 14 years. Four birth cohorts were formed according to the major historical events of the 20th century (1916-1928; 1929-1938; 1939-1945; 1946-1962). CR was operationalized by merging education, complexity of occupation, and verbal IQ. We used linear mixed-effect models to evaluate the effects of CR and birth cohorts on rate of performance change over time. Age at baseline, baseline structural brain health (total brain and total white matter hyperintensities volumes), and baseline vascular risk factors burden were used as covariates.

RESULTS

CR was only associated with slower decline in verbal episodic memory. However, more recent birth cohorts predicted slower annual cognitive decline in all domains, except for executive functions. This effect increased as the birth cohort became more recent.

CONCLUSION

We found that both CR and birth cohorts influence future cognitive decline, which has strong public policy implications.

Today's Older Adults Are Cognitively Fitter Than Older Adults Were 20 Years Ago, but When and How They Decline Is No Different Than in the Past

History-graded increases in older adults' levels of cognitive performance are well documented, but little is known about historical shifts in within-person change: cognitive decline and onset of decline. We combined harmonized perceptual-motor speed data from independent samples recruited in 1990 and 2010 to obtain 2,008 age-matched longitudinal observations (M = 78 years, 50% women) from 228 participants in the Berlin Aging Study (BASE) and 583 participants in the Berlin Aging Study II (BASE-II). We used nonlinear growth models that orthogonalized within- and between-person age effects and controlled for retest effects. At age 78, the later-born BASE-II cohort substantially outperformed the earlier-born BASE cohort (d = 1.20; 25 years of age difference). Age trajectories, however, were parallel, and there was no evidence of cohort differences in the amount or rate of decline and the onset of decline. Cognitive functioning has shifted to higher levels, but cognitive decline in old age appears to proceed similarly as it did two decades ago.

Long-Term Effects of Cognitive Training on All-Cause Mortality in US Older Adults

Objectives: Cognitive abilities have been implicated as predictors of mortality in older adults. This study examines the effects of cognitive training on mortality 20 years post-intervention. Methods: Data come from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) randomized control trial (N = 2802). Participants were cognitively and physically healthy, community-dwelling adults aged 65 and older. Cox proportional hazard models were used to investigate (1) the association between baseline cognition and mortality risk and (2) the effect of ACTIVE cognitive training (memory, reasoning, and speed of processing) on mortality risk 20 years post-intervention. Results: Higher baseline cognition predicted lower mortality risk 20 years post-intervention. No significant effects of ACTIVE cognitive training in memory, reasoning, or speed of processing on mortality risk were observed. Discussion: More work is needed to identify cognitive training interventions that may lead to lower mortality risks in later adulthood.

Sex and gender differences in dementia

The dementia landscape has undergone a striking paradigm shift. The advances in understanding of neurodegeneration and proteinopathies has changed our approach to patients with cognitive impairment. Firstly, it has recently been shown that the various proteinopathies that are the cause of the dementia begin to build up long before the appearance of any obvious symptoms. This has cemented the idea that there is an urgency in diagnosis as it occurs very late in the pathophysiology of these diseases. Secondly, that accurate diagnosis is required to deliver targeted therapies, that is precision medicine. With this latter point, the realization that various factors of a person need to be considered as they may impact the presentation and progression of disease has risen to the forefront. Two of these factors aside from race and age are biological sex and gender (social construct), as both can have tremendous impact on manifestation of disease. This chapter will cover what is known and remains to be known on the interaction of sex and gender with some of the major causes of dementia.

Better cognitive function in younger generations - Insights from two cohort studies of middle-aged to older adults in Wisconsin

BACKGROUND

Understanding generational trends in dementia and cognitive decline is essential to quantify future healthcare needs and may help identify interventions and preventions. We aimed to determine whether individuals from more recent generations showed better neurocognitive function.

METHODS

This cross-sectional study combined data from 4439 participants (mean age 64 years (SD = 13); 57% were women) from the Epidemiology of Hearing Loss Study and Beaver Dam Offspring Study. We assessed participants' birth cohort (1901-1924, Greatest Generation; 1925-1945, Silent Generation; 1946-1964, Baby Boom Generation; 1965-1984, Generation X) and neurocognition (Trail-Making Tests A and B, Digit Symbol Substitution Test, Auditory Verbal Learning Test, Verbal Fluency Test). Multivariable linear regression models were utilized.

RESULTS

Adjusted for age, sex, education, and known risk factors for cognitive decline, more recent generations showed better processing speed, executive function, attention, and verbal fluency than the Greatest Generation. Largest benefits were found in the Baby Boom Generation. Compared with the Greatest Generation, individuals from the Baby Boom Generation performed better on Trail-Making Tests A (-0.21 ln(time in s); 95% confidence interval (CI) -0.29, -0.13) and B (-0.31 ln(time in s); 95% CI -0.40, -0.22), Digit Symbol Substitution Test (6.07 numbers correct; 95% CI 3.61, 8.52) and Verbal Fluency Test (8.75 numbers correct; 95% CI 5.07, 12.42 in women; 5.28 numbers correct; 95% CI 0.79, 9.78 in men), with effect sizes similar to effects of 11-15 years of less aging.

CONCLUSIONS

This indicates that some benefits of younger generations might be related to yet unknown and potentially modifiable environmental, health-related or lifestyle factors and motivates research of such underlying factors to promote healthy cognitive aging.

Attention Performance Decline After Age 40 in Clinically Normal Community Dwellers: Evidence from a 10-Year Follow-Up of the Yakumo Study

Age-related changes in attention ability and differences by gender in the rates of change from middle age were investigated. Digit Cancellation Test (D-CAT1 and D-CAT3 conditions, which involve low and high cognitive load, respectively) scores and individually calculated decline rates (DRs) in 10-year follow-up among four age groups (40s, 50s, 60s, and 70s) were examined. Performance in both D-CAT conditions declined with increasing age from the 50s to the 70s, whereas there was no difference between the 40s and 50s, and a gender difference (with the women showing an advantage) was demonstrated in the 40s and 50s groups on the D-CAT3. In the D-CAT1 condition, the DR remained stable from the 40s to the 50s but increased from the 50s and to the 60s and then remained the same. In the D-CAT3 condition, the DR became larger even after the 70s. The DRs did not differ between men and women from middle age onward. Although DRs showed no gender difference, D-CAT performance showed a gender difference, with men being about 20% less capable by the age of 40. We suggest that data showing concrete declines in attentional performance after middle age may be used to reduce accidents encountered in the daily life of older adults.

Acting Like a Baby Boomer? Birth-Cohort Differences in Adults' Personality Trajectories During the Last Half a Century

Society and developmental theory generally assume that there are wide generational differences in personality. Yet evidence showing historical change in the levels of adult Big Five traits is scarce and particularly so for developmental change. We tracked adult trajectories of personality in 4,732 participants (age: M = 52.93 years, SD = 16.69; 53% female) from the Seattle Longitudinal Study (born 1883-1976) across 50 years. Multilevel models revealed evidence for historical change in personality: At age 56, later-born cohorts exhibited lower levels of maturity-related traits (agreeableness and neuroticism) and higher levels of agency-related traits (extraversion and openness) than earlier-born cohorts. Historical changes in agreeableness and neuroticism were more pronounced among young adults, but changes in openness were less pronounced. Cohort differences in change were rare and were observed only for agreeableness; within-person increases were more pronounced among later-born cohorts. Our results yield the first evidence for historical change in the Big Five across adulthood and point to the roles of delayed social-investment and maturity effects.

Differences in Cognitive Functioning in Two Birth Cohorts Born 20 Years Apart: Data from the Interdisciplinary Longitudinal Study of Ageing

We compared neuropsychological functioning and prevalence of mild cognitive impairment (MCI) in two birth cohorts born 20 years apart when participants had reached the same age, i.e., the mid-60s. The study followed up 500 volunteers born 1930–1932 (C30) and 502 born 1950–1952 (C50). Participants underwent medical, neuropsychological, and psychiatric examinations in 1993–1996 (T1), 1997–2000 (T2), 2005–2008 (T3), and 2014–2016 (T4), including assessment of abstract thinking, memory performance, verbal fluency, visuo-spatial thinking, psychomotor speed, and attention. Healthy participants from C30 at T2 (n = 298) and from C50 at T4 (n = 205) were compared using multivariate ANCOVAs. Groups slightly differed with respect to age (C50: 63.86 ± 1.14 vs. C30: 66.80 ± 0.91; p < 0.05) and years of education (13.28 ± 2.89 vs. 14.56 ± 2.45). After correcting for age, C50 significantly outperformed C30 in all domains except concentration and verbal fluency. After additionally adjusting for education, C50 significantly outperformed C30 in declarative memory performances and abstract thinking only. Prevalence rates of MCI were 25.2% in C30 and 9.6% in C50 (p < 0.001). Our findings confirm the association between better educational attainment and enhanced cognitive performance in “younger” old individuals. While this association corresponds to the Flynn effect, various life course influences may have also contributed to better performance, including improvements in healthcare provision, medication, and lifestyle factors. Their overall effects may foster cognitive reserve and thus translate into the decline in MCI prevalence reported here.

Trends in Cognitive Function Among Chinese Elderly From 1998 to 2018: An Age-Period-Cohort Analysis

Objectives: To investigate the effects of age, period, and cohort (APC) on trends in cognitive function among the Chinese elderly, and to explore how gender gaps in cognitive function change with age, period, and cohort. Methods: This study used data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 1998 to 2018, and included 90,432 participants aged above 65 years old. The measurement of cognitive function was the score of the Mini-Mental State Examination (MMSE). Cross-classified random-effect models were used to investigate age, period, and cohort trends in cognitive function. Results: Mini-Mental State Examination scores decreased with age at an increasing rate. While the cohort effect was nearly stable, the period effect demonstrated a downward trend from 1998 to 2002 followed by a nearly flat line. Females were associated with lower MMSE scores than males. When age increased, the gender gaps in MMSE scores further increased. The period-based gender gaps in MMSE scores diverged throughout the 20 years, while the cohort-based gender disparities in MMSE scores converged with successive cohorts. Conclusions: Age, period, and cohort had different and independent effects on cognitive function among the Chinese elderly. The effect of age was stronger than that of period and cohort. Gender disparities in cognitive function increased with age and period, and decreased with successive cohorts.

Birth Cohorts and Cognitive Reserve Influence Cognitive Performances in Older Adults

BACKGROUND

Evidence suggests birth cohort differences in cognitive performance of older adults. Proxies of cognitive reserve (CR), such as educational attainment and occupational complexity, could also partly account for these differences as they are influenced by the sociocultural environment of the birth cohorts.

OBJECTIVE

To predict cognitive performance using birth cohorts and CR and examine the moderating influence of CR on cognitive performance and structural brain health association.

METHODS

Using ADNI data (n = 1628), four birth cohorts were defined (1915-1928; 1929-1938; 1939-1945; 1946-1964). CR proxies were education, occupational complexity, and verbal IQ. We predicted baseline cognitive performances (verbal episodic memory; language and semantic memory; attention capacities; executive functions) using multiple linear regressions with CR, birth cohorts, age, structural brain health (total brain volume; total white matter hyperintensities volume) and vascular risk factors burden as predictors. Sex and CR interactions were also explored.

RESULTS

Recent birth cohorts, higher CR, and healthier brain structures predicted better performance in verbal episodic memory, language and semantic memory, and attention capacities, with large effect sizes. Better performance in executive functions was predicted by a higher CR and a larger total brain volume, with a small effect size. With equal score of CR, women outperformed men in verbal episodic memory and language and semantic memory in all cohorts. Higher level of CR predicted better performance in verbal episodic memory, only when total brain volume was lower.

CONCLUSION

Cohort differences in cognitive performance favor more recent birth cohorts and suggests that this association may be partly explained by proxies of CR.

The Effects of Selective Survival on Black Adults' Cognitive Development

OBJECTIVES

The theory of selective survival suggests that possibly around 70-75 years of age, Blacks may display substantive changes in their pattern of cognitive decline. This study examined the age-graded pattern of cognitive decline within older Blacks by describing a trend that characterizes differences in the change of cognitive decline from ages 51.5 to 95.5, and hypothesized that this age-graded pattern is nonlinear.

METHOD

Utilizing 2 waves of longitudinal data from the Baltimore Study of Black Aging, this study used multilevel modeling to test whether the interaction between age and the 3-year study period (time between waves) had a positive effect on changes in inductive reasoning, declarative memory, working memory, and perceptual speed.

RESULTS

A significant positive interaction between age and wave was found for inductive reasoning, demonstrating an age-grade pattern of change/decline in cognitive pattern for Blacks aged 51.5-95.4. Simple slope probing via the Johnson-Neyman Technique suggested that Black adults ~64 years and younger experienced significant decline in inductive reasoning across study time, whereas for those older than 63.71, the decline was nonsignificant. No significant age-wave interactions were found for declarative memory, working memory, or perceptual speed.

DISCUSSION

Findings suggest a selective survival effect for inductive reasoning ability among Blacks. With decline evident so early, common cognitive intervention programs targeting adults 65+ may come too late for Blacks, signifying the importance and urgency for early health interventions and public policy designed to promote cognitive reserve.

Sex differences in dementia and response to a lifestyle intervention: Evidence from Nordic population-based studies and a prevention trial

INTRODUCTION

Evidence on sex differences in the risk for dementia has been mixed. The goal was to assess sex differences in the development of dementia, and in the effects of a lifestyle intervention.

METHODS

Two strategies were adopted, one using combined data from three large Nordic population-based cohort studies (n = 2289), adopting dementia as outcome, and 2-year multidomain lifestyle intervention (n = 1260), adopting cognitive change as outcome.

RESULTS

There was higher risk for dementia after age 80 years in women. The positive effects of the lifestyle intervention on cognition did not significantly differ between men and women. Sex-specific analyses suggested that different vascular, lifestyle, and psychosocial risk factors are important for women and men in mid- and late-life.

CONCLUSION

Women had higher risk for dementia among the oldest individuals. Lifestyle interventions may be effectively implemented among older men and women.

A quick test of cognitive speed (AQT): regression-based norms for cognitively healthy 80 to 94-year olds

Slowed processing speed is part of normal aging but also a symptom of many diseases, including dementia. A Quick Test of Cognitive Speed (AQT) consists of three conditions: color naming (AQT1), form naming (AQT2) and dual color-form naming (AQT3) and offers a user-friendly assessment of processing speed that is used internationally to identify cognitive impairment in elderly patients. Appropriate age-norms have however been lacking. This study provides regression-based norms derived from a Swedish sample of 158 cognitively healthy 80 to 94-year olds. The results show age effects in all three conditions, a non-linear education effect in AQT1, and age by gender interactions in AQT2 and AQT3: men performed worse with increasing age, but women remained on a par. However, irrespective of age and gender, AQT2 and AQT3 mean raw and predicted scores were slower than the hitherto recommended cutoff criteria for suspected cognitive impairment.

Cognition in Healthy Aging

The study of cognitive change across a life span, both in pathological and healthy samples, has been heavily influenced by developments in cognitive psychology as a theoretical paradigm, neuropsychology and other bio-medical fields; this alongside the increase in new longitudinal and cohort designs, complemented in the last decades by the evaluation of experimental interventions. Here, a review of aging databases was conducted, looking for the most relevant studies carried out on cognitive functioning in healthy older adults. The aim was to review not only longitudinal, cross-sectional or cohort studies, but also by intervention program evaluations. The most important studies, searching for long-term patterns of stability and change of cognitive measures across a life span and in old age, have shown a great range of inter-individual variability in cognitive functioning changes attributed to age. Furthermore, intellectual functioning in healthy individuals seems to decline rather late in life, if ever, as shown in longitudinal studies where age-related decline of cognitive functioning occurs later in life than indicated by cross-sectional studies. The longitudinal evidence and experimental trials have shown the benefits of aerobic physical exercise and an intellectually engaged lifestyle, suggesting that bio-psycho-socioenvironmental factors concurrently with age predict or determine both positive or negative change or stability in cognition in later life.

Birth cohort differences in cognitive performance in 75- and 80-year-olds: a comparison of two cohorts over 28 years

Objective

To evaluate cohort differences in cognitive performance in older men and women born and assessed 28 years apart.

Methods

Data in this study were drawn from two age-homogeneous cohorts measured in the same laboratory using the same standardized cognitive performance tests. Participants in the first cohort were born in 1910 and 1914 and assessed in 1989–1990 (Evergreen project, n = 500). Participants in the second cohort were born in 1938 or 1939 and 1942 or 1943 and assessed in 2017–2018 (Evergreen II, n = 726). Participants in both cohorts were assessed at age 75 and 80 years and were recruited from the population register. Cognitive performance was measured using the Digit Span test from the Wechsler Memory Scale (WMS), Digit Symbol test from the Wechsler Adult Intelligence Scale (WAIS) and phonemic Verbal Fluency test from the Schaie-Thurstone Adult Mental Abilities Test. Reaction time assessing motor and mental responses was measured with a simple finger movement task, followed by a complex finger movement task. T-tests were used to study cohort differences and linear regression models to study possible factors underlying differences.

Results

We found statistically significant cohort differences in all the cognitive performance tests, except for the digit span test and simple movement task in men, the later-born cohort performing better in all the measured outcomes.

Conclusions

The results of this study provide strong evidence that cognitive performance is better in more recent cohorts of older people compared to their counterparts measured 28 years earlier.

Generations and Generational Differences: Debunking Myths in Organizational Science and Practice and Paving New Paths Forward

Talk about generations is everywhere and particularly so in organizational science and practice. Recognizing and exploring the ubiquity of generations is important, especially because evidence for their existence is, at best, scant. In this article, we aim to achieve two goals that are targeted at answering the broad question: "What accounts for the ubiquity of generations despite a lack of evidence for their existence and impact?" First, we explore and "bust" ten common myths about the science and practice of generations and generational differences. Second, with these debunked myths as a backdrop, we focus on two alternative and complementary frameworks-the social constructionist perspective and the lifespan development perspective-with promise for changing the way we think about age, aging, and generations at work. We argue that the social constructionist perspective offers important opportunities for understanding the persistence and pervasiveness of generations and that, as an alternative to studying generations, the lifespan perspective represents a better model for understanding how age operates and development unfolds at work. Overall, we urge stakeholders in organizational science and practice (e.g., students, researchers, consultants, managers) to adopt more nuanced perspectives grounded in these models, rather than a generational perspective, to understand the influence of age and aging at work.

Effects of Matcha Green Tea Powder on Cognitive Functions of Community-Dwelling Elderly Individuals

Matcha Green Tea Powder contains a variety of active ingredients beneficial to health, such as tea catechins, lutein and vitamin K. It is also known that these ingredients confer benefits upon cognitive functions of elderly people. Therefore, we aimed to investigate the relationship between a daily supplementation of Matcha and the change in cognitive functions of community-dwelling elderly people. A randomized, double-blind, placebo-controlled 12-week trial was performed. Sixty-one participants were recruited and randomly assigned to receive test drink containing 3 g powder from fresh Matcha or placebo powder per day. Changes in cognitive function were assessed utilizing a psychometric test battery. Daily food intake was assessed by a Brief-type Self-administered Diet History Questionnaire (BDHQ). In the gender-specific analysis, a significant cognitive enhancement was observed in the Montreal Cognitive Assessment (MoCA) score in the active group of women. In dietary analysis, we found a significant inverse correlation between consumption of vitamin K in daily diet, excluding test drinks, and change in MoCA. The present study suggests that daily supplementation of Matcha Green Tea Powder has protective effects against cognitive decline in community-dwelling elderly women.

Are Advances in Survival Among the Oldest Old Seen Across the Spectrum of Health and Functioning?

BACKGROUND

Mortality rates have been reduced by half over the last 60 years for nonagenarians, and the progress is continuing. The greater survival might be due to overtreatment of severely physically and cognitively disabled individuals, which is a big concern for societies and individuals.

METHODS

The study population comprised two Danish birth cohorts: the 1905 Cohort and the 1915 Cohort. At age 95, all from the two cohorts who were still alive and living in Denmark were invited to participate in a health survey that used the same assessment instrument. A total of 2,670 (56.8%) persons participated in the two surveys and survival was assessed through a 7.3-year follow-up period during which 2,497 (93.5%) had died, and with virtually no loss to follow-up.

RESULTS

Despite the increasing chance of surviving to age 95, the 1915 Cohort had significantly better health and functioning than the 1905 Cohort. The survival advantage in the 1915 Cohort continued in the follow-up period after age 95: Median survival length was 2.4 months longer, p = .011. This advantage was not statistically associated with different levels of activities of daily living, physical performance, cognitive functioning, self-rated health and life satisfaction. However, the advantage tended to be more pronounced among people with better health.

CONCLUSIONS

Life span and health increases among the oldest old. The improvement in survival for 95-year olds born in 1915 compared with 1905 was seen across the whole spectrum of health and functioning, with a tendency towards bigger improvement among those in good health.

Cognitive Diversity in a Healthy Aging Cohort: Cross-Domain Cognition in the Cam-CAN Project

Objective: Studies of "healthy" cognitive aging often focus on a limited set of measures that decline with age. The current study argues that defining and supporting healthy cognition requires understanding diverse cognitive performance across the lifespan. Method: Data from the Cambridge Centre for Aging and Neuroscience (Cam-CAN) cohort was examined across a range of cognitive domains. Performance was related to lifestyle including education, social engagement, and enrichment activities. Results: Results indicate variable relationships between cognition and age (positive, negative, or no relationship). Principal components analysis indicated maintained cognitive diversity across the adult lifespan, and that cognition-lifestyle relationships differed by age and domain. Discussion: Our findings support a view of normal cognitive aging as a lifelong developmental process with diverse relationships between cognition, lifestyle, and age. This reinforces the need for large-scale studies of cognitive aging to include a wider range of both ages and cognitive tasks.

Education and Cognitive Functioning Across the Life Span

Cognitive abilities are important predictors of educational and occupational performance, socioeconomic attainment, health, and longevity. Declines in cognitive abilities are linked to impairments in older adults' everyday functions, but people differ from one another in their rates of cognitive decline over the course of adulthood and old age. Hence, identifying factors that protect against compromised late-life cognition is of great societal interest. The number of years of formal education completed by individuals is positively correlated with their cognitive function throughout adulthood and predicts lower risk of dementia late in life. These observations have led to the propositions that prolonging education might (a) affect cognitive ability and (b) attenuate aging-associated declines in cognition. We evaluate these propositions by reviewing the literature on educational attainment and cognitive aging, including recent analyses of data harmonized across multiple longitudinal cohort studies and related meta-analyses. In line with the first proposition, the evidence indicates that educational attainment has positive effects on cognitive function. We also find evidence that cognitive abilities are associated with selection into longer durations of education and that there are common factors (e.g., parental socioeconomic resources) that affect both educational attainment and cognitive development. There is likely reciprocal interplay among these factors, and among cognitive abilities, during development. Education-cognitive ability associations are apparent across the entire adult life span and across the full range of education levels, including (to some degree) tertiary education. However, contrary to the second proposition, we find that associations between education and aging-associated cognitive declines are negligible and that a threshold model of dementia can account for the association between educational attainment and late-life dementia risk. We conclude that educational attainment exerts its influences on late-life cognitive function primarily by contributing to individual differences in cognitive skills that emerge in early adulthood but persist into older age. We also note that the widespread absence of educational influences on rates of cognitive decline puts constraints on theoretical notions of cognitive aging, such as the concepts of cognitive reserve and brain maintenance. Improving the conditions that shape development during the first decades of life carries great potential for improving cognitive ability in early adulthood and for reducing public-health burdens related to cognitive aging and dementia.

A New Look at Cohort Trend and Underlying Mechanisms in Cognitive Functioning

OBJECTIVES

The prevalence of dementia in the United States seems to have declined over the last few decades. We investigate trends and their underlying mechanisms in cognitive functioning (CF) across 7 decades of birth cohorts from the Greatest Generation to Baby Boomers.

METHODS

Data come from 30,191 participants of the 1996-2014 Health and Retirement Study. CF is measured as a summary score on a 35-point cognitive battery of items. We use generalized linear models to examine the trends in CF and explanatory variables across birth cohorts. Then, Karlson-Holm-Breen decomposition method is used to evaluate the contribution of each explanatory variable to the trend of CF.

RESULTS

CF has been improving from the Greatest Generation to Late Children of Depression and War Babies, but then significantly declines since the Early-Baby Boomers and continues into Mid-Baby Boomers. This pattern is observed universally across genders, race/ethnicities, education groups, occupations, income, and wealth quartiles. The worsening CF among Baby Boomers does not originate from childhood conditions, adult education, or occupation. It can be attributed to lower household wealth, lower likelihood of marriage, higher levels of loneliness, depression and psychiatric problems, and more cardiovascular risk factors (e.g., obesity, physical inactivity, hypertension, stroke, diabetes, and heart disease).

DISCUSSION

The worsening CF among Baby Boomers may potentially reverse past favorable trends in dementia as they reach older ages and cognitive impairment becomes more common if no effective interventions and policy responses are in place.

Age-Varying Relationships Between Physical Function and Cognition in Older Adulthood

OBJECTIVES

There are positive relationships between physical and cognitive function in older adulthood; however, the strength of these relationships are inconsistent across studies. Although novel statistical tools provide flexibility to explore age-related differences in relationship magnitude, such methods have not been implemented in gerontological research. This study applied such methods to examine variations in relationship magnitude between physical function and cognition in healthy older adults (N = 2,783).

METHOD

Time-varying effects modeling (TVEM) is an extension of regression that models changes in relationships as a function of time-varying metrics like age. TVEM was used to examine if physical function (Turn 360, grip strength) predicted cognitive performance (memory, processing speed/attention, and reasoning) similarly across adults aged 65-90.

RESULTS

All associations between Turn 360 and all cognitive domains were significant and positive; however, speed of processing had significant magnitude variation across age such that the young-old and the old-old demonstrated the strongest relationships. Associations between grip strength and all cognitive domains significantly strengthened with increased age.

DISCUSSION

Results suggest that depending on the sample age, there may be inconsistencies in the relationships between physical and cognitive performance. Future research should explore these relationships longitudinally to better elucidate discrepant findings.

Genetic variation underlying cognition and its relation with neurological outcomes and brain imaging

Cognition in adults shows variation due to developmental and degenerative components. A recent genome-wide association study identified genetic variants for general cognitive function in 148 independent loci. Here, we aimed to elucidate possible developmental and neurodegenerative pathways underlying these genetic variants by relating them to functional, clinical and neuroimaging outcomes. This study was conducted within the population-based Rotterdam Study (N=11,496, mean age 65.3±9.9 years, 58.0% female). We used lead variants for general cognitive function to construct a polygenic score (PGS), and additionally excluded developmental variants at multiple significance thresholds. A higher PGS was related to more years of education (β=0.29, p=4.3x10^-7) and a larger intracranial volume (β=0.05, p=7.5x10^-4). To a smaller extent, the PGS was associated with less cognitive decline (β_ΔG-factor=0.03, p=1.3x10^-3), which became non-significant after adjusting for education (p=1.6x10^-2). No associations were found with daily functioning, dementia, parkinsonism, stroke or microstructural white matter integrity. Excluding developmental variants attenuated nearly all associations. In conclusion, this study suggests that the genetic variants identified for general cognitive function are acting mainly through the developmental pathway of cognition. Therefore, cognition, assessed cross-sectionally, seems to have limited value as a biomarker for neurodegeneration.

The Increasing Importance of Friendship in Late Life: Understanding the Role of Sociohistorical Context in Social Development

Historically, family ties have been understood as the primary source of support for aging adults, and past empirical and theoretical work has highlighted the tendency of older adults to focus on close family. However, in line with demographic changes and historical increases in the diversity of social structures, friendships are increasing in importance in recent generations of older adults. Given the powerful role of context in shaping these changes, this paper offers a conceptual analysis linking individual agency to sociohistorical context as a way to understand this increasing diversity of social ties. More specifically, we propose that the individual invests time and energy to form and maintain social ties, and that each individual has a specific social opportunity structure (all potential ties that are available to invest in, as well as the costs of those investments). Furthermore, this investment of time and energy is determined in part by individual differences in capacities and motivations. We argue that sociohistorical context influences this process in three important ways: (1) in its effect on the social opportunity structure; (2) in its direct effect on time and energy; and (3) in its effect on individuals' capacities and motivations. We believe that these mechanisms can account for the increasing diversity of social ties across adulthood, as well as the potential for future historical changes.

Parallel Progress in Perceived Age and Life Expectancy

BACKGROUND

Human life expectancy continues to rise in most populations. This rise not only leads to longer lives but also is accompanied by improved health at a given age, that is, recent cohorts show a reduction of biological age for a given chronological age. Despite or even because of the diversity of biomarkers of aging, an accurate quantification of a general shift in biological age across time has been challenging.

METHODS

Here, we compared age perception of facial images taken in 2001 over a decade and related these changes in age perception to changes in life expectancy.

RESULTS

We show that age perception changes substantially across time and parallels the progress in life expectancy. In 2012, people aged more than 70 years needed to look 2.3 years younger to be rated the same age as in 2002.

CONCLUSIONS

Our results suggest that age perception reflects the past life events better than predicts future length of life, that is, it is written in your face how much you have aged so far. We draw this conclusion as age perception among elderly individuals paralleled changes in life expectancy at birth but not changes in remaining life expectancies. We suggest that changes in age perception should be explored for younger age classes to inform on aging processes, including whether aging is delayed or slowed with increasing life expectancy.

Secular trends in cognitive trajectories of diverse older adults

INTRODUCTION

This study aimed to determine if later birth year influences trajectory of age-related cognitive decline across racial/ethnic groups and to test whether years of school, childhood socioeconomic status, and cardiovascular disease burden explain such secular trends.

METHODS

We compared cognitive trajectories of global cognition and subdomains in two successive racially/ethnically and educationally diverse birth cohorts of a prospective cohort study.

RESULTS

Later birth year was associated with higher initial cognitive levels for Whites and Blacks, but not Hispanics. Later birth year was also associated with less rapid rate of decline in all three racial/ethnic groups. More years of education, higher childhood socioeconomic status, and, to a smaller extent, greater cardiovascular disease burden accounted for higher intercepts in the later-born cohort, but did not account for attenuated slope of cognitive decline.

DISCUSSION

Later birth year is related to a slower rate of age-related decline in some cognitive domains in some racial/ethnic groups. Our analyses suggest that racial/ethnic and social inequalities are part of the mechanisms driving secular trends in cognitive aging and dementia.

Sex Differences in Neuropsychological Test Performance in Alzheimer's Disease and the Influence of the ApoE Genotype

BACKGROUND

Only few studies exist reporting sex differences in the Alzheimer disease (AD) patients regarding cognitive profile, brain damage, and risk factors. The present study investigated the influence of sex in combination with the Alzheimer risk allele, ε4-allele of apolipoprotein E, on cognitive performance.

MATERIALS AND METHODS

We examined the effect of sex and ApoE genotype on a range of neuropsychological markers from the German version of the Consortium to Establish a Registry in Alzheimer's Disease Neuropsychological Battery in a monocentric study of 399 AD patients.

RESULTS

Male patients had significantly more years of school and occupational education compared with women. Male AD patients outperformed female patients in tasks of object naming, constructional praxis, and constructional praxis recall. There was no statistically significant interaction effect between sex and ε4-allele of apolipoprotein E for any of the examined variables.

CONCLUSIONS

The superiority of healthy men compared with women in tasks of object naming, constructional praxis, and visual memory seems to remain stable when people develop AD, indicating larger cognitive reserves in men. In contrast, findings that cognitively healthy women outperform men in tests of verbal memory and verbal fluency are not stable in AD. Further studies are needed to gain insight in the reasons for sex differences.

Cohort Differences in Cognitive Aging in the Longitudinal Aging Study Amsterdam

Objectives

This study aims to examine cohort differences in cognitive performance and rates of change in episodic memory, processing speed, inductive reasoning, and general cognitive performance and to investigate whether these cohort effects may be accounted for by education attainment.

Method

The first cohort (N = 705) was born between 1920 and 1930, whereas the second cohort (N = 646) was born between 1931 and 1941. Both birth cohorts were aged 65 to 75 years at baseline and were followed up 3 and 6 years later. Data were analyzed using linear mixed models.

Results

The later born cohort had better general cognitive performance, inductive reasoning, and processing speed at baseline, but cohort differences in inductive reasoning and general cognitive performance disappeared after adjusting for education. The later born cohort showed steeper decline in processing speed. Memory decline was steeper in the earlier born cohort but only from Time 1 to Time 3 when the same memory test was administered. Education did not account for cohort differences in cognitive decline.

Discussion

The later born cohort showed better initial performance in certain cognitive abilities, but no better preservation of cognitive abilities overtime compared with the earlier born cohort. These findings carry implications for healthy cognitive aging.

Generational Differences in the 5-Year Incidence of Age-Related Macular Degeneration

Importance

Whether a reported decline in the risk of developing age-related macular degeneration (AMD) continued for people born during the Baby Boom years (1946-1964) or later is unknown. These data are important to plan for ocular health care needs in the 21st century.

Objectives

To determine whether the 5-year risk for AMD declined by generation and to identify factors that contributed to improvement in risk.

Design, Setting, and Participants

Data came from the longitudinal cohort Beaver Dam Eye Study (March 1, 1988, through September 15, 1990, and March 1, 1993, through June 15, 1995) and the Beaver Dam Offspring Study (June 8, 2005, through August 4, 2008, and July 12, 2010, through March 21, 2013). These population-based studies examined residents of Beaver Dam, Wisconsin, aged 43 to 84 years in 1987 through 1988 and their adult offspring aged 21 to 84 years in 2005 through 2008. A total of 4819 participants were at risk for developing AMD based on fundus images obtained at baseline visits. Data were analyzed from February 18, 2016, through June 22, 2017, with additional analyses ending September 22, 2017.

Main Outcomes and Measures

Fundus images were graded for AMD using the Wisconsin Age-related Maculopathy Grading System. The incidence of AMD was defined as the presence at the 5-year follow-up examination of pure geographic atrophy or exudative macular degeneration, any type of drusen with pigmentary abnormalities, or soft indistinct drusen without pigmentary abnormalities.

Results

Among the 4819 participants, the mean (SD) baseline age of the cohort was 54 (11) years; 2117 were men (43.9%) and 2702 were women (56.1%). The 5-year age- and sex-adjusted incidence of AMD was 8.8% in the Greatest Generation (born during 1901-1924), 3.0% in the Silent Generation (born during 1925-1945), 1.0% in the Baby Boom Generation (born during 1946-1964), and 0.3% in Generation X (born during 1965-1984). Adjusting for age and sex, each generation was more than 60% less likely to develop AMD than the previous generation (relative risk, 0.34; 95% CI, 0.24-0.46). The generational association (relative risk, 0.40; 95% CI, 0.28 to 0.57) remained significant after adjusting for age, sex, smoking, educational attainment, exercise, levels of non–high-density lipoprotein cholesterol and high-sensitivity C-reactive protein, and use of nonsteroidal anti-inflammatory drugs, statins, and multivitamins.

Conclusions and Relevance

The 5-year risk for AMD declined by birth cohorts throughout the 20th century. Factors that explain this decline in risk are not known. However, this pattern is consistent with reported declines in risks for cardiovascular disease and dementia, suggesting that aging Baby Boomers may experience better retinal health at older ages than did previous generations.

Comparison of cognitive and physical functioning of Europeans in 2004-05 and 2013

Background

Adult mortality has been postponed over time to increasingly high ages. However, evidence on past and current health trends has been mixed, and little is known about European disability trends.

Methods

In a cross-sectional setting, we compared cognitive and physical functioning in same-aged Europeans aged 50+ between 2004–05 (wave 1; n = 18 757) and 2013 (wave 5 refresher respondents; n = 16 696), sourced from the Survey of Health, Ageing and Retirement in Europe (SHARE).

Results

People in 2013 had better cognitive function compared with same-aged persons in 2004–05, with an average difference of approximately one-third standard deviation. The same level of cognitive function in 2004–05 at age 50 was found in 2013 for people who were 8 years older. There was an improvement in cognitive function in all European regions. Mean grip strength showed an improvement in Northern Europe of 1.00 kg [95% confidence interval (CI) 0.65; 1.35] and in Southern Europe of 1.68 kg (95% CI 1.14; 2.22), whereas a decrease was found in Central Europe (-0.80 kg; 95% CI −1.16; −0.44). We found no overall differences in activities of daily living (ADL), but small improvements in instrumental activities of daily living (IADL) in Northern and Southern Europe, with an improvement in both ADL and IADL from age 70 in Northern Europe.

Conclusions

Our results indicate that later-born Europeans have substantially better cognitive functioning than earlier-born cohorts. For physical functioning, improvements were less clear, but for Northern Europe there was an improvement in ADL and IADL in the oldest age groups.

Age trajectories of independence in daily living among the oldest old in China

With the rapid increase in the population of the oldest old (those aged 80 and over), there is some concern how longer life might be associated with a loss of independence in daily living. Addressing the trajectory of loss of independence for the oldest old is challenging, not only because the oldest old are heterogeneous, but also because the health trajectories at the population level may noticeably differ from those at the individual level. We used the 1998, 2000, 2002, 2005 and 2008 waves of the Chinese Longitudinal Healthy Longevity Study to assess the age trajectories of the loss of independence for three cohorts born in 1909-1918, 1899-1908 and 1893-1898, respectively, both at the individual and the population levels. Independence was measured by combining the activities of daily living and the Chinese version of the mini-mental state examination. Controlling for various confounding factors, particularly the selectivity due to death and loss to follow-up, we found that, while more recent cohorts had higher initial levels of independence, this was followed by a faster decline compared to the earlier cohorts. Also, their level of independence fell below that of their earlier born counterparts at the same ages. Decomposition analysis further illustrated that the decline of independence at the population level is more gradual than that at the individual level. This finding can be largely attributed to selective mortality and loss to follow-up. For instance, the population prevalence of independence for the 1893-1898 female cohort declined slightly, from 19.7 to 11.1% in 1998-2008, while the proportion for females who survived from 1998 to 2008 dropped from 66.7 to 11.1%. For the population as a whole, a longer life expectancy does not necessarily result in a rapid decline of independence. For individuals, longer life expectancy accompanies deterioration of independence.

Sex-dependent effect of the BDNF Val66Met polymorphism on executive functioning and processing speed in older adults: evidence from the health ABC study

Brain-derived neurotrophic factor (BDNF) Val66Met polymorphism may be an important source of heterogeneity seen in cognitive aging, although the specific relationship between this polymorphism and cognition remains controversial and may depend on the sex of participants. We assessed 2668 older black and white adults and fit linear mixed models to digit symbol substitution test (DSST) performance assessed in years 0 (baseline), 4, 7, and 9 to examine the interaction between sex and BDNF genotype on the intercept (i.e., estimated baseline DSST) and change in DSST over 9 years, adjusted for covariates. Sex interacted with BDNF genotype to predict DSST intercept (F[1,1599] = 7.4, p < 0.01) and 9-year change (F[1,1183] = 4.1, p = 0.04) in white participants only. Initially, white male Val/Val carriers had lower DSST scores (37.6, SE = 0.8) in comparison with male Met carriers (difference, -1.7; 95% CI, -3.2 to -0.3) and female Val/Val carriers (difference, -5.6; 95% CI, -6.8 to -4.3). White female Met carriers showed a slower rate of change (annual rate of change = -0.6, SE = 0.1) in comparison with female Val/Val carriers (difference, -0.2; 95% CI, -0.4 to -0.02) and male Met carriers (difference, -0.3; 95% CI, -0.5 to -0.02). Our findings suggest that BDNF Val66Met and sex should be considered in future endeavors aimed at treating or preventing neurodegenerative disorders.

Temporal Trends in the Level and Decline of Cognition and Disability in an Elderly Population: The PAQUID Study

In line with declining trends in dementia incidence, we compared the cognitive and functional evolution of 2 "generations" of elderly individuals aged 78-88 years, who were included 10 years apart in the French Personnes Agées Quid cohort (n = 612 in 1991-1992 and n = 628 in 2001-2002) and followed-up for 12 years with assessments of cognition and disability. The impact of specific risk factors on this evolution was evaluated. Differences between the generations in baseline levels and decline over time were estimated using a joint model to account for differential attrition. Compared with the first generation, the second generation had higher performances at baseline on 4 cognitive tests (from P < 0.005). Differences in global cognition, verbal fluency, and processing speed, but not in working memory, were mostly explained by improvement in educational level. The second generation also exhibited less cognitive decline in verbal fluency and working memory. Progression of disability was less over the follow-up period for the second generation than for the first. The cognitive state of this elderly population improved, partially due to improvements in educational level.

Education Does Not Affect Cognitive Decline in Aging: A Bayesian Assessment of the Association Between Education and Change in Cognitive Performance

Education is positively associated with level of cognitive function but the association between education and rate of cognitive decline remains unresolved, partly for methodological reasons. In this article, we address this issue using linear mixed models and Bayesian hypothesis testing, using data from the Betula cohort-sequential longitudinal study. Our results support the null hypothesis that education does not alter the rate of cognitive decline for visuospatial ability, semantic knowledge, and episodic memory. We propose that education is only a relevant variable for understanding cognitive performance in older age because of the association between performance and education that is formed in early development.

Age variations in cohort differences in the United States: Older adults report fewer constraints nowadays than those 18 years ago, but mastery beliefs are diminished among younger adults

Life Span psychological and life course sociological perspectives have long acknowledged that individual functioning is shaped by historical and sociocultural contexts. Secular increases favoring later-born cohorts are widely documented for fluid cognitive performance and well-being (among older adults). However, little is known about secular trends in other key resources of psychosocial function such as perceptions of control and whether historical changes have occurred in young, middle-aged, and older adults alike. To examine these questions, we compared data from two independent national samples of the Midlife in the United States survey obtained 18 years apart (1995/96 vs. 2013/14) and identified case-matched cohorts (per cohort, n = 2,223, aged = 23-75 years) based on age and gender. We additionally examined the role of economic resources for cohort differences in perceived mastery and constraints. Results revealed that older adults in later-born cohorts reported perceiving fewer constraints than did matched controls 18 years ago, with such positive secular trends being particularly pronounced among women. In contrast, younger adults reported perceiving more constraints in later-born cohorts than those 18 years ago and also reported perceiving lower mastery. We conclude from our national U.S. sample that secular trends generalize to central psychosocial resources across adulthood, such as perceptions of control, but are not unanimously positive. We discuss possible underlying mechanisms and practical implications. (PsycINFO Database Record

Secular Trends in Cognitive Performance in Older Black and White U.S. Adults, 1993-2012: Findings From the Chicago Health and Aging Project

Objective

To characterize secular trends from 1993 to 2012 in cognitive performance using a cohort of older black and white U.S. adults, and compare trends by race.

Method

Our data come from 8,906 participants of the Chicago Health and Aging Project (CHAP), a longitudinal, population-based cohort (age ≥ 67, 60% black). Participants underwent cognitive assessments in six 3-year study cycles from 1993 to 1996 through 2010 to 2012. We computed 3 measures of cognitive performance: global cognition, episodic memory, and perceptual speed.

Results

Mean performance in terms of global cognitive score followed a secular pattern of modest decline over the 6 study cycles. The trend was most pronounced for perceptual speed. Mean scores among black participants were consistently lower than those for whites; these disparities in mean performance narrowed over time, especially on perceptual speed, but appeared to widen at the last cycle. Global scores among the upper quartile of performers rose slightly, but scores among the lowest quartile of performers dropped precipitously.

Discussion

Between 1993 and 2012, secular trends in cognitive performance in this established cohort did not follow a clear pattern of improvement, contrasting with previous research. But patterns differed by cognitive domain, performance level, and race.

Aging and Decision-Making: A Conceptual Framework for Future Research - A Mini-Review

Age differences in decision-making are of theoretical interest and have important practical implications, but relevant lines of work are distributed across multiple disciplines and often lack integration. The present review proposes an overarching conceptual framework with the aim of connecting disjointed aspects of this field of research. The framework builds on process models of decision-making and specifies potential mechanisms behind age effects as well as relevant moderators including task characteristics and contextual factors. After summarizing the extant literature for each aspect of the framework, compensatory mechanisms and ecological fit between different components of the model are considered. Implications for real-life decision-making, remaining research gaps, and directions for future research are discussed.

As You Sow, So Shall You Reap: Gender-Role Attitudes and Late-Life Cognition

Some studies have found that women outperform men in episodic memory after midlife. But is this finding universal, and what are the reasons? Gender differences in cognition are the result of biopsychosocial interactions throughout the life course. Social-cognitive theory of gender development posits that gender roles may play an important mediating role in these interactions. We analyzed country differences in the gender differential in cognition after midlife using data from individuals age 50 and above ( N = 226,661) from 27 countries. As expected, older women performed relatively better in countries characterized by more equal gender-role attitudes. This result was robust to cohort differences as well as reverse causality. The effect was partially mediated by education and labor-force participation. Cognition in later life thus cannot be fully understood without reference to the opportunity structures that sociocultural environments do (or do not) provide. Global population aging raises the importance of understanding that gender roles affect old-age cognition and productivity.