An Exploratory Study

This study mainly intended to disentangle the role played by physical reserve as a mediator of the relationship between cognitive reserve and global cognitive functioning in older people aging well. A sample of 120 67-101-year-old community-dwellers was recruited in the Sardinian Blue Zone, an area characterized by the extreme longevity of its inhabitants. Each respondent completed a battery of tests examining cognitive functioning, perceived physical health, cognitive reserve, and physical reserve (objectively assessed through accelerometric-derived measures). Significant associations were found among measures of cognitive reserve, physical reserve, perceived physical health, and cognition. Besides, two mediational analyses pointed out that physical reserve and distinct indexes of cognitive reserve explained 18% and 32% of the variance associated with global cognitive functioning. In conclusion, the combination of high cognitive reserve and more preserved motor functioning seems to contribute to the maintenance of healthy cognition in older people aging well.

Critical periods for cognitive reserve building activities for late life global cognition and cognitive decline: the Sydney memory and aging cohort study

Cognitive, social, and physical activities, collectively linked to cognitive reserve, are associated with better late-life cognitive outcomes. To better understand the building of cognitive reserve, we investigated which of these activities, during which stages of life, had the strongest associations with late-life cognitive performance. From the Sydney Memory and Aging Study, 546 older Australians, who were community-dwelling and without a dementia diagnosis at recruitment (Mage 80.13 years, 52.2% female), were asked about their engagement in social, physical, and cognitive activities throughout young adulthood (YA), midlife (ML), and late-life (LL). Comprehensive neuropsychological testing administered biennially over 6 years measured baseline global cognition and cognitive decline. In our study, YA, but not ML nor LL, cognitive activity was significantly associated with late-life global cognition (β = 0.315, p < .001). A follow-up analysis pointed to the formal education component of the YA cognitive activity measure, rather than YA cognitive leisure activities, as a significant predictor of better late-life global cognition (β = 0.146, p = .003). YA social activity and LL cognitive activity were significantly associated with less cognitive decline (β = 0.023, p < .001, and β = 0.016, p = .022, respectively). Physical activity was not found to be associated with global cognition or cognitive decline. Overall, YA cognitive activity was associated with better late-life cognition, and YA social and LL cognitive activities were associated with less cognitive decline. Formal education emerges as the key contributor in the association between YA cognitive activity and late-life global cognition.

Cognitive reserve over the life course and risk of dementia: a systematic review and meta-analysis

Background

The number of people with dementia is soaring. Cognitive reserve has been thought to be associated with dementia risk. It is not clear at which period in the life course and which cognitive reserve proxies contribute to the reduced risk of dementia.

Methods

By scanning four databases (PubMed, Embase, Web of Science, and MEDLINE) up to Jun 3, 2023, longitudinal studies of life-course cognitive reserve and risk of dementia were found. The HRs and 95% CIs for each study were summarized using random effects models. Subgroup analyses and sensitivity analyses were conducted. Utilizing funnel plots, Begg and Egger tests, publication bias was investigated.

Results

A total of 27 studies were included, containing 10 in early-life, 10 in middle-life, and 13 in late-life. All studies used validated questionnaires to measure cognitive reserve, and dementia diagnosis followed recognized worldwide guidelines. All included studies were of medium or low risk. Cognitive reserve in early-life (Hazard ratio (HR): 0.82; 95% confidence interval (CI): 0.79-0.86), middle-life (HR: 0.91; 95% CI: 0.84-0.98) and late-life (HR: 0.81; 95% CI: 0.75-0.88) all have protective effects on dementia risk. Multiple sensitivity analyses showed consistent results.

Conclusion

Dementia risk is reduced by the buildup of cognitive reserves during life-course. Accumulation of proxies for cognitive reserve in early and late life had the greatest effect on dementia risk reduction. Social connection may be an effective approach to lower dementia risk.

Cognitive reserve in ALS: the role of occupational skills and requirements

OBJECTIVE

Amyotrophic Lateral Sclerosis (ALS) is a heterogeneous neurodegenerative condition featuring variable degrees of motor and cognitive impairment. We assessed the impact of specific, empirically derived occupational skills and requirements on cognitive and motor functioning in ALS.

METHODS

Individuals with ALS (n = 150) were recruited from the University of Pennsylvania's Comprehensive ALS Clinic. The Edinburgh Cognitive and Behavioral ALS Screen (ECAS) measured cognition, and the Penn Upper Motor Neuron (PUMNS) and ALS Functional Rating Scales (ALSFRS-R) measured motor symptoms. We derived 17 factors representing distinct occupational skills and requirements from the Occupational Information Network (O*NET), which were related to cognitive and motor scores using multiple linear regression.

RESULTS

Occupational roles involving greater reasoning ability (β = 2.12, p < .05), social ability (β = 1.73, p < .05), analytic skills, (β = 3.12, p < .01) and humanities knowledge (β = 1.83, p<.01) were associated with better performance on the ECAS, while jobs involving more exposure to environmental hazards (β=-2.57, p < .01) and technical skills (β=-2.16, p<.01) were associated with lower ECAS scores. Jobs requiring more precision skills (β = 1.91, p < .05) were associated with greater motor dysfunction on the PUMNS.

CONCLUSIONS

Occupational histories involving more cognitively complex skills and activities were related to preserved cognitive functioning in ALS consistent with the cognitive reserve hypothesis, while jobs with greater exposure to environmental hazards and technical demands were linked to poorer cognitive functioning. Jobs involving more repetitive movements were associated with worse motor functioning, possibly due to overuse. Occupational history provides insight into protective and risk factors for variable degrees of cognitive and motor dysfunction in ALS.

Neighborhood disadvantage reduces cognitive reserve independent of neuropathologic change

INTRODUCTION

Individuals in socioeconomically disadvantaged neighborhoods exhibit increased risk for impaired cognitive function. Whether this association relates to the major dementia-related neuropathologies is unknown.

METHODS

This cross-sectional study included 469 autopsy cases from 2011 to 2023. The relationships between neighborhood disadvantage measured by Area Deprivation Index (ADI) percentiles categorized into tertiles, cognition evaluated by the last Mini-Mental State Examination (MMSE) scores before death, and 10 dementia-associated proteinopathies and cerebrovascular disease were assessed using regression analyses.

RESULTS

Higher ADI was significantly associated with lower MMSE score. This was mitigated by increasing years of education. ADI was not associated with an increase in dementia-associated neuropathologic change. Moreover, the significant association between ADI and cognition remained even after controlling for changes in major dementia-associated proteinopathies or cerebrovascular disease.

DISCUSSION

Neighborhood disadvantage appears to be associated with decreased cognitive reserve. This association is modified by education but is independent of the major dementia-associated neuropathologies.

Small vessel disease and cognitive reserve oppositely modulate global network redundancy and cognitive function: A study in middle-to-old aged community participants

Cerebral small vessel disease (SVD) can disrupt the global brain network and lead to cognitive impairment. Conversely, cognitive reserve (CR) can improve one's cognitive ability to handle damaging effects like SVD, partly by optimizing the brain network's organization. Understanding how SVD and CR collectively influence brain networks could be instrumental in preventing cognitive impairment. Recently, brain redundancy has emerged as a critical network protective metric, providing a nuanced perspective of changes in network organization. However, it remains unclear how SVD and CR affect global redundancy and subsequently cognitive function. Here, we included 121 community-dwelling participants who underwent neuropsychological assessments and a multimodal MRI examination. We visually examined common SVD imaging markers and assessed lifespan CR using the Cognitive Reserve Index Questionnaire. We quantified the global redundancy index (RI) based on the dynamic functional connectome. We then conducted multiple linear regressions to explore the specific cognitive domains related to RI and the associations of RI with SVD and CR. We also conducted mediation analyses to explore whether RI mediated the relationships between SVD, CR, and cognition. We found negative correlations of RI with the presence of microbleeds (MBs) and the SVD total score, and a positive correlation of RI with leisure activity-related CR (CRI-leisure). RI was positively correlated with memory and fully mediated the relationships between the MBs, CRI-leisure, and memory. Our study highlights the potential benefits of promoting leisure activities and keeping brain redundancy for memory preservation in older adults, especially those with SVD.

Effects of cognitive reserve on cognitive frailty among older adults: A population-based prospective cohort study

AIM

We investigated the effect of lifespan cognitive reserve and its components on cognitive frailty among older adults.

METHODS

A total of 4922 participants aged ≥65 years were recruited in 2008 and were followed up in 2011 from the Chinese Longitudinal Healthy Longevity Survey. Cognitive frailty was determined through the simultaneous presence of physical frailty (pre-frailty or frailty) and mild cognitive impairment, excluding concurrent dementia. The assessment of physical frailty and mild cognitive impairment was based on the Fatigue, Resistence, Ambulation, Illness, Loss of weight (FRAIL) (Fatigue, Resistence, Ambulation, Illness, Loss) and Mini-Mental State Examination scale, respectively. The lifespan cognitive reserve consisted of education attainment, occupational complexity and later-life leisure activities. We used logistic regression models to estimate the risk of cognitive frailty associated with the lifespan cognitive reserve and its components.

RESULTS

A higher level of lifespan cognitive reserve, higher educational attainment or leisure activities engagement, but not occupational complexity, were associated with lower risk of incident cognitive frailty. Furthermore, cognitive, social and physical activities were associated with lower risk of incident cognitive frailty.

CONCLUSION

Cognitive reserve, particularly educational attainment and leisure activities, can protect from cognitive frailty. This implicates that individuals should accumulate cognitive reserve in their lifespan, and older adults should actively participate in leisure activities to prevent cognitive frailty. Geriatr Gerontol Int 2024; 24: 398-403.

Protective effect of bilingualism on aging, MCI, and dementia: A community-based study

INTRODUCTION

Lifelong bilingualism is associated with a delayed age at onset of dementia, but evidence from community-based studies is limited. We investigated the relationship between bilingualism and the prevalence of cognitive impairment in a linguistically diverse community.

METHODS

A door-to-door community study was conducted from January to December 2021 in urban Bengaluru, India. 1234 individuals aged ≥60 years participated in the study. Participants were diagnosed with no cognitive impairment (NCI), mild cognitive impairment (MCI), or dementia using established diagnostic criteria.

RESULTS

Dementia prevalence was higher in monolinguals (4.9%) than bilinguals (0.4%) (P = .001). The prevalence of MCI was also higher in monolinguals (8.5%) than bilinguals (5.3%) (P = .001). The study also revealed better cognitive function in bilinguals than monolinguals with NCI, after controlling for confounding variables.

DISCUSSION

The current study provides significant support for the protective effect of bilingualism on cognitive impairment in an urban community with extensive bilingual interactional contexts in everyday life.

HIGHLIGHTS

Bilingualism has been demonstrated to protect against dementia and mild cognitive impairment in a linguistically diverse community with extensive code-switching contexts. Bilingual older individuals had superior baseline cognitive performance compared to monolingual older individuals. Bilingualism was found to have an independent effect on general cognition after adjusting for major social determinants of health in the group without cognitive impairment.

Cognitive Reserve and Frontotemporal Disorders: Exploring the Relationship Between Education, Physical Activity, and Cognitive Dysfunction in Older Adults

In this study we investigated the relationship between cognitive reserve (CR) proxies, such as education, physical activity (PA), and cognitive dysfunction (CD) in the presence or absence of frontotemporal disorders (FTD). Previous research has suggested that education and PA may delay the onset of CD and reduce the risk of developing dementia. However, it remains unclear whether these CR proxies can protect against CD when FTD is present. We aimed to explore this relationship and determine whether sustained CR may be evident regardless of FTD. We recruited 149 older adults (aged 65-99 years) from community centers where they were voluntarily participating in leisure activities. We used bioelectrical impedance to measure their body composition, and we administered the International PA Questionnaire and the Mini-Mental State Examination to measure their PA and cognitive function, respectively. We used the Frontal Assessment Battery to screen for frontotemporal dementia. Our results showed that people with FTD were older, had lower education, and engaged in less PA, relative to other participants. Regression models revealed that age, education, and PA were significant predictors of FTD. More specifically, FTD was negatively associated with cognitive functioning, and there were significant interaction effects between FTD and education and PA. PA and education were significant predictors of cognitive functioning, and, when values for PA and education were high, they offset the effects of FTD on cognitive function. These findings support impressions that PA and years of education provide an insulating or compensatory effect on cognitive functioning in older adults with executive dysfunction or frontotemporal dementia, highlighting the importance of encouraging both pursuits.

Post-stroke cognitive impairment remains highly prevalent and disabling despite state-of-the-art stroke treatment

BACKGROUND

State-of-the-art stroke treatment significantly reduces lesion size and stroke severity, but it remains unclear whether these therapeutic advances have diminished the burden of post-stroke cognitive impairment (PSCI).

AIMS

In a cohort of patients receiving modern state-of-the-art stroke care including endovascular therapy, we assessed the frequency of PSCI and the pattern of domain-specific cognitive deficits, identified risk factors for PSCI, and determined the impact of acute PSCI on stroke outcome.

METHODS

In this prospective monocentric cohort study, we examined patients with first-ever anterior circulation ischemic stroke without pre-stroke cognitive decline, using a comprehensive neuropsychological assessment ⩽10 days after symptom onset. Normative data were stratified by demographic variables. We defined PSCI as at least moderate (<1.5 standard deviation) deficits in ⩾2 cognitive domains. Multivariable regression analysis was applied to define risk factors for PSCI.

RESULTS

We analyzed 329 non-aphasic patients admitted from December 2020 to July 2023 (67.2 ± 14.4 years old, 41.3% female, 13.1 ± 2.7 years of education). Although most patients had mild stroke (median National Institutes of Health Stroke Scale (NIHSS) 24 h = 1.00 (0.00; 3.00); 87.5% with NIHSS ⩽ 5), 69.3% of them presented with PSCI 2.7 ± 2.0 days post-stroke. The most severely and often affected cognitive domains were verbal learning, episodic memory, executive functions, selective attention, and constructive abilities (39.1%-51.2% of patients), whereas spatial neglect was less frequent (18.5%). The risk of PSCI was reduced with more years of education (odds ratio (OR) = 0.47, 95% confidence interval (CI) = 0.23-0.99) and right hemisphere lesions (OR = 0.47, 95% CI = 0.26-0.84), and increased with stroke severity (NIHSS 24 h, OR = 4.19, 95% CI = 2.72-6.45), presence of hyperlipidemia (OR = 1.93, 95% CI = 1.01-3.68), but was not influenced by age. After adjusting for stroke severity and depressive symptoms, acute PSCI was associated with poor functional outcome (modified Rankin Scale > 2, F = 13.695, p < 0.001) and worse global cognition (Montreal Cognitive Assessment (MoCA) score, F = 20.069, p < 0.001) at 3 months post-stroke.

CONCLUSION

Despite modern stroke therapy and many strokes having mild severity, PSCI in the acute stroke phase remains frequent and associated with worse outcome. The most prevalent were learning and memory deficits. Cognitive reserve operationalized as years of education independently protects post-stroke cognition.

Considering the response in addition to the challenge - a narrative review in appraisal of a motor reserve framework

The remarkable increase in human life expectancy over the past century has been achieved at the expense of the risk of age-related impairment and disease. Neurodegeneration, be it part of normal aging or due to neurodegenerative disorders, is characterized by loss of specific neuronal populations, leading to increasing clinical impairment. The individual course may be described as balance between aging- or disease-related pathology and intrinsic mechanisms of adaptation. There is plenty of evidence that the human brain is provided with exhaustible resources to maintain function in the face of adverse conditions. While a reserve concept has mainly been coined in cognitive neuroscience, emerging evidence suggests similar mechanisms to underlie individual differences of adaptive capacity within the motor system. In this narrative review, we summarize what has been proposed to date about a motor reserve (mR) framework. We present current evidence from research in aging subjects and people with neurological conditions, followed by a description of what is known about potential neuronal substrates of mR so far. As there is no gold standard of mR quantification, we outline current approaches which describe various indicators of mR. We conclude by sketching out potential future directions of research. Expediting our understanding of differences in individual motor resilience towards aging and disease will eventually contribute to new, individually tailored therapeutic strategies. Provided early diagnosis, enhancing the individual mR may be suited to postpone disease onset by years and may be an efficacious contribution towards healthy aging, with an increased quality of life for the elderly.

Cognitive resilience/reserve: Myth or reality? A review of definitions and measurement methods

INTRODUCTION

This review examines the concept of cognitive reserve (CR) in relation to brain aging, particularly in the context of dementia and its early stages. CR refers to an individual's ability to maintain or regain cognitive function despite brain aging, damage, or disease. Various factors, including education, occupation complexity, leisure activities, and genetics are believed to influence CR.

METHODS

We revised the literature in the context of CR. A total of 842 articles were identified, then we rigorously assessed the relevance of articles based on titles and abstracts, employing a systematic approach to eliminate studies that did not align with our research objectives.

RESULTS

We evaluate-also in a critical way-the methods commonly used to define and measure CR, including sociobehavioral proxies, neuroimaging, and electrophysiological and genetic measures. The challenges and limitations of these measures are discussed, emphasizing the need for more targeted research to improve the understanding, definition, and measurement of CR.

CONCLUSIONS

The review underscores the significance of comprehending CR in the context of both normal and pathological brain aging and emphasizes the importance of further research to identify and enhance this protective factor for cognitive preservation in both healthy and neurologically impaired older individuals.

HIGHLIGHTS

This review examines the concept of cognitive reserve in brain aging, in the context of dementia and its early stages. We have evaluated the methods commonly used to define and measure cognitive reserve. Sociobehavioral proxies, neuroimaging, and electrophysiological and genetic measures are discussed. The review emphasizes the importance of further research to identify and enhance this protective factor for cognitive preservation.

Estimation of cognitive reserve and its impact on cognitive performance in older adults

OBJECTIVES

Cognitive reserve provides evidence in the search for answers regarding the role that lifestyle has in the protection of cognition in old age. Through a structural equations model, different things were analyzed: the relative weight of education, occupational complexity, free time activities and the intelligence quotient in cognitive reserve; and its impact on three cognitive domains: memory, language and executive functions.

DESIGN

A trail analysis was executed, using structural equations procedure.

PARTICIPANTS

167 older participants (mean = 76.74 years, standard deviation = 6.8 years).

MEASUREMENTS

Participants were assessed with: Sociodemographic Questionnaire, Occupational Activity Agency Questionnaire, Social Participation Questionnaire and Neuropsychological Evaluation Battery for: memory, language and executive functions.

RESULTS

The cognitive reserve factor is well represented by the measures included, with values ​​between .43 and .86, and shows a direct effect on language (β = .52, p < .001), executive functions (β = .77, p <.001), and memory (β = .36, p = .003).

CONCLUSIONS

In conclusion, lifestyle factors, such as education, occupational complexity, leisure time activities and intelligence quotient have an impact on the conformation of cognitive reserve and performance in some psychological processes.

Cognitive reserve proxies for individuals with intellectual developmental disability: A scoping review

BACKGROUND

Cognitive reserve (CR) has not been studied in people with Intellectual Developmental Disability, a population with a high incidence of dementia. Commonly adopted CR proxies should be adapted to reflect more specifically the experiences of people with Intellectual Developmental Disability.

METHOD

This scoping review intended to identify CR proxies relevant to people with this condition.

RESULTS

Some of these were the same already detected in a population without intellectual disabilities (education, occupation, physical activity, leisure, community and social activities); others were found to be specifically relevant for this population: type of schooling, parental educational level, environmental stimulation and living place.

CONCLUSIONS

These proxies need to be considered in studies on CR and Intellectual Developmental Disability and in clinical practice. Research on the protective effect of CR aims to encourage policies promoting lifestyle-based educational and preventive interventions and overcome participation barriers for people with Intellectual Developmental Disability.

Cognitive Reserve in Parkinson's Disease without Dementia: β-Amyloid and Metabolic Assessment

BACKGROUND

Cognitive reserve (CR) is the mismatch between preserved cognition and neuropathological damage. Amyloidopathy in Parkinson's disease (PD) could be associated with faster progression to dementia, but the putative protective effect of CR is unknown.

OBJECTIVES

To evaluate the effect of CR on β-amyloid burden and brain metabolism in non-demented PD subjects.

METHODS

Participants with PD (n = 53) underwent a clinical evaluation, [18 F]-fluorodeoxyglucose and [18 F]-flutemetamol positron emission tomography magnetic resonances, and were classified according to CR. The metabolic pattern of 16 controls was compared to PD subjects.

RESULTS

The PD subjects showed hypometabolism mainly in the bilateral posterior cortex. Superior-CR subjects (n = 22) exhibited better cognitive performance, increased amyloid burden, and higher metabolism in several right hemisphere areas compared to low-medium-CR subjects (n = 31).

CONCLUSIONS

Higher CR in non-demented PD is associated with better cognitive performance, which might reduce vulnerability to the effect of β-amyloid. Whether superior CR leads to protection against metabolic deterioration, and predominantly right hemisphere involvement, deserves further exploration.

Correlations between cognitive reserve, gray matter, and cerebrospinal fluid volume in healthy elders and mild cognitive impairment patients

Objective

To explore the effect of cognitive reserve (CR) on brain volume and cerebrospinal fluid (CSF) in patients with mild cognitive impairment (MCI) and healthy elders (HE).

Methods

31 HE and 50 MCI patients were collected in this study to obtain structural MRI, cognitive function, and composite CR scores. Educational attainment, leisure time, and working activity ratings from two groups were used to generate cognitive reserve index questionnaire (CRIq) scores. The different volumes of brain regions and CSF were obtained using uAI research portal in both groups, which were taken as the regions of interest (ROI), the correlation analysis between ROIs and CRIq scores were conducted.

Results

The scores of CRIq, CRIq-leisure time, and CRIq-education in HE group were significantly higher than patients in MCI group, and the montreal cognitive assessment (MoCA) and minimum mental state examination (MMSE) scores were positively correlated with the CRIq, CRIq-education in both groups, and were positively correlated with CRIq-leisure time in MCI group. The scores of auditory verbal learning test (AVLT) and verbal fluency test (VFT) were also positively correlated with CRIq, CRIq-leisure time, and CRIq-education in MCI group, but the score of AVLT was only positively correlated with CRIq in HE group. Moreover, in MCI group, the volume of the right middle cingulate cortex and the right parahippocampal gyrus were negatively correlated with the CRIq, and the volume of CSF, peripheral CSF, and third ventricle were positively correlated with the CRIq-leisure time score. The result of mediation analysis suggested that right parahippocampal gryus mediated the main effect of the relationship between CRIq and MoCA score in MCI group.

Conclusion

People with higher CR show better levels of cognitive function, and MCI patients with higher CR showed more severe volume atrophy of the right middle cingulate cortex and the right parahippocampal gyrus, but more CSF at a given level of global cognition.

Association of cognitive reserve with the risk of dementia in the UK Biobank: role of polygenic factors

BACKGROUND

It remains unclear whether cognitive reserve can attenuate dementia risk among people with different genetic predispositions.

AIMS

We aimed to examine the association between cognitive reserve and dementia, and further to explore whether and to what extent cognitive reserve may modify the risk effect of genetic factors on dementia.

METHOD

Within the UK Biobank, 210 631 dementia-free participants aged ≥60 years were followed to detect incident dementia. Dementia was ascertained through medical and death records. A composite cognitive reserve indicator encompassing education, occupation and multiple cognitively loaded activities was created using latent class analysis, categorised as low, moderate and high level. Polygenic risk scores for Alzheimer's disease were constructed to evaluate genetic risk for dementia, categorised by tertiles (high, moderate and low). Data were analysed using Cox models and Laplace regression.

RESULTS

In multi-adjusted Cox models, the hazard ratio (HR) of dementia was 0.66 (95% confidence interval (CI) 0.61-0.70) for high cognitive reserve compared with low cognitive reserve. In Laplace regression, participants with high cognitive reserve developed dementia 1.62 (95% CI 1.35-1.88) years later than those with low cognitive reserve. In stratified analysis by genetic risk, high cognitive reserve was related to more than 30% lower dementia risk compared with low cognitive reserve in each stratum. There was an additive interaction between low cognitive reserve and high genetic risk on dementia (attributable proportion 0.24, 95% CI 0.17-0.31).

CONCLUSIONS

High cognitive reserve is associated with reduced risk of dementia and may delay dementia onset. Genetic risk for dementia may be mitigated by high cognitive reserve. Our findings underscore the importance of enhancing cognitive reserve in dementia prevention.

Cognitive reserve and the risk of postoperative neurocognitive disorders in older age

Background

Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are postoperative neurocognitive disorders (PNDs) that frequently occur in the aftermath of a surgical intervention. Cognitive reserve (CR) is a concept posited to explain why cognitive health varies between individuals. On this qualitative understanding of cognitive health, factors like IQ, education level, and occupational complexity can affect the impact of neuropathological processes on cognitive outcomes.

Methods

We investigated the association between CR and POD and CR and POCD on data from 713 patients aged≥65 years with elective surgery. Peak pre-morbid IQ was estimated from vocabulary. Occupational complexity was coded according to the Dictionary of Occupational Titles (DOT). Education level was classed according to the International Standard Classification of Education (ISCED). These three factors were used as proxies of CR. In a series of regression models, age, sex, depression, site of surgery, and several lifestyle and vascular factors were controlled for.

Results

Patients with a higher IQ had lower odds of developing POD. We found no significant association between the other two CR markers with POD. None of the CR markers was associated with POCD.

Conclusion

The significant association of a higher IQ with lower POD risk allows for the stratification of elderly surgical patients by risk. This knowledge can aid the prevention and/or early detection of POD. Further research should attempt to determine the lack of associations of CR markers with POCD in our study.

Impact of cognitive reserve on bipolar disorder: a systematic review

Background

Cognitive reserve (CR) is a complex concept that includes premorbid IQ, years of education, and exposure to neuropsychological stimuli through work and leisure. Previous studies have suggested that CR has a positive impact on several aspects of bipolar disorder. Synthesizing the evidence to date is an important work in providing directions for future studies. The objectives of this systematic review to summary impact of CR on onsetting, relapsing bipolar episodes, buffering cognitive dysfunctions, and maintaining quality of life (QOL) in bipolar disorder.

Methods

Two researchers independently reviewed selected paper from three database as PubMed, PsychINFO, and Web of Science. The search keywords were "bipolar disorder" and "cognitive reserve." The selected studies were classified as the levels of evidence according to the criteria of the Oxford Center for Evidence- Based Medicine. The results of the selected studies were summarized according to the objectives.

Results

Thrity six studies were included in this review. People with high CR may have fewer bipolar episodes and alleviate cognitive impairments and dysfunction. CR may keep the functional level in patients with bipolar disorder.

Conclusion

The results of this systematic review suggest that CR may be involved in preventing relapse of bipolar episodes and may alleviate cognitive dysfunction. However, effect on prevention of onset-risk and relapse of bipolar episodes need further investigation in prospective studies.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021270293, the protocol was registered with PROSERO (CRD42021270293).

A 2-year longitudinal randomized controlled trial examining the transfer of speed of processing training to secondary cognitive domains in middle-aged and older adults with HIV-associated neurocognitive disorder: Results of the think fast study

OBJECTIVE

As people with HIV (PWH) age, they are at-risk of developing cognitive impairments compared to their seronegative counterparts. Although speed of processing (SOP) training may help improve this cognitive ability, less work has examined transfer to other cognitive domains. This study examined the effect of SOP training has on secondary cognitive domains in PWH aged 40+ years.

METHOD

In this 3-group 2-year longitudinal study, 216 PWH with HIV-associated neurocognitive disorder (HAND) or borderline HAND were randomized to either: (1) 10 h of SOP training (n = 70); (2) 20 h of SOP training (n = 73); or (3) 10 h of an active control training (n = 73). Participants completed a comprehensive cognitive battery at baseline, immediately after training, and at 1 and 2 years. This battery yielded global and domain specific T-scores as well as a cognitive impairment variable. Generalized linear mixed-effect models were fitted to estimate between-group mean differences at the follow-up time-points adjusted for baseline.

RESULTS

No clinically or statistically significant improvements in any of the cognitive outcomes were observed. A sensitivity analysis was conducted; conclusions replicated those of the main analysis, with two exceptions: Global Function T and Psychomotor Speed T showed relevant training improvements among the intervention groups over the control group at the immediate post time point.

CONCLUSIONS

Although SOP training has been shown to improve cognitive abilities that correspond to driving and mobility, such training has limited therapeutic utility in improving cognition in other domains in PWH with HAND.

Can Creativity and Cognitive Reserve Predict Psychological Well-Being in Older Adults? The Role of Divergent Thinking in Healthy Aging

The maintenance of psychological well-being (PWB) in the older adult population is a pivotal goal for our rapidly aging society. PWB is a multicomponent construct that can be influenced by several factors in the lifespan. The beneficial role of divergent thinking (DT) and cognitive reserve (CR) in sustaining older subjects' PWB has been scarcely investigated so far. The present study aims to investigate the relationships between DT, CR, and PWB in a sample of 121 healthy older adults (61 females; M age: 73.39 ± 6.66 years; M education: 11.33 ± 4.81 years). The results highlight that better DT performance predicts higher CR, which mediates an indirect positive effect of DT on emotional competence, one of the PWB factors. It follows that DT and CR can be considered protective factors in aging, and their effects go beyond cognitive functioning, revealing a positive effect even on some PWB components. The practical implications regarding targeted health interventions for prevention in the older adult population to support well-being and promote healthy aging are discussed.

Genetic Predisposition for White Matter Hyperintensities and Risk of Mild Cognitive Impairment and Alzheimer's Disease: Results from the HELIAD Study

The present study investigated the association of genetic predisposition for white matter hyperintensities (WMHs) with incident amnestic mild cognitive impairment (aMCI) or Alzheimer's disease (AD), as well as whether such an association was influenced by age, sex, and cognitive reserve. Overall, 537 individuals without aMCI or dementia at baseline were included. Among them, 62 individuals developed aMCI/AD at follow up. Genetic propensity to WMH was estimated using a polygenic risk score for WMHs (PRS WMH). The association of PRS WMH with aMCI/AD incidence was examined using COX models. A higher PRS WMH was associated with a 47.2% higher aMCI/AD incidence (p = 0.015) in the fully adjusted model. Subgroup analyses showed significant results in the older age group, in which individuals with a higher genetic predisposition for WMHs had a 3.4-fold higher risk for developing aMCI/AD at follow up (p < 0.001), as well as in the lower cognitive reserve (CR, proxied by education years) group, in which individuals with a higher genetic predisposition for WMHs had an over 2-fold higher risk (p = 0.013). Genetic predisposition for WMHs was associated with aMCI/AD incidence, particularly in the group of participants with a low CR. Thus, CR might be a modifier in the relationship between genetic predisposition for WMHs and incident aMCI/AD.

Adaptation of the Concept of Brain Reserve for the Prediction of Stroke Outcome: Proxies, Neural Mechanisms, and Significance for Research

The prediction of stroke outcome is challenging due to the high inter-individual variability in stroke patients. We recently suggested the adaptation of the concept of brain reserve (BR) to improve the prediction of stroke outcome. This concept was initially developed alongside the one for the cognitive reserve for neurodegeneration and forms a valuable theoretical framework to capture high inter-individual variability in stroke patients. In the present work, we suggest and discuss (i) BR-proxies-quantitative brain characteristics at the time stroke occurs (e.g., brain volume, hippocampus volume), and (ii) proxies of brain pathology reducing BR (e.g., brain atrophy, severity of white matter hyperintensities), parameters easily available from a routine MRI examination that might improve the prediction of stroke outcome. Though the influence of these parameters on stroke outcome has been partly reported individually, their independent and combined impact is yet to be determined. Conceptually, BR is a continuous measure determining the amount of brain structure available to mitigate and compensate for stroke damage, thus reflecting individual differences in neural resources and a capacity to maintain performance and recover after stroke. We suggest that stroke outcome might be defined as an interaction between BR at the time stroke occurs and lesion load. BR in stroke can potentially be influenced, e.g., by modifying cardiovascular risk factors. In addition to the potential power of the BR concept in a mechanistic understanding of inter-individual variability in stroke outcome and establishing individualized therapeutic approaches, it might help to strengthen the synergy of preventive measures in stroke, neurodegeneration, and healthy aging.

The Effect of COVID-19 on Middle-Aged Adults' Mental Health: A Mixed-Method Case-Control Study on the Moderating Effect of Cognitive Reserve

The COVID-19 pandemic has increased the vulnerability of adults to mental health effects, and the study of protective factors has become crucial. Cognitive reserve (CR) is a well-known protective factor against cognitive decline and several health factors; however, its protective effect on mental health during the pandemic has been rarely addressed. Thus, this study explored, through a mixed-method design, the effect of CR on perceived distress and PTSD-like symptoms in middle-aged participants who have survived severe COVID-19 and a matched control group. A total of 432 participants filled out self-report measures of CR, PTSD, depression, and anxiety, and were also asked to provide narration about their COVID-19-related experience. COVID-19 significantly affected the chances of reporting different mental health symptoms; levels of CR played a protective role in reducing their severity. Moreover, adults with higher CR seemed to be more realistic, focusing less on positive emotions, and elaborating more on the sense of anxiety when describing their experience: this might be an indication of a lower use of suppression to regulate emotions. Practical implications of these findings and future directions have been also discussed.

Relationship between lifestyle proxies of cognitive reserve and cortical regions in older adults

Introduction

With the rapid increase in the population over 65 years old, research on healthy aging has become one of the priorities in the research community, looking for a cost-effective method to prevent or delay symptoms of mild cognitive disorder or dementia. Studies indicate that cognitive reserve theory could be beneficial in this regard. The aim of this study was to investigate the potential relationship between lifestyle socio-behavioral proxies of cognitive reserve and cortical regions in adults with no subjective cognitive decline.

Methods

Overall, 58 participants, aged 65-85 years, were included in the data analysis (M = 71.83, SD = 5.02, 20.7% male). Cognitive reserve proxies were measured using the Cognitive Reserve Index questionnaire, while cortical volumes were obtained with the Siemens 1.5 T Avanto MRI scanner and further mapped using the Desikan-Killiany-Tourville (DKT) Atlas. Estimated intracranial volume and age were used as covariates.

Results

The results indicated that higher occupational complexity was associated with larger cortical volume in the left middle temporal gyrus, the left and right inferior temporal gyrus, and the left inferior parietal lobule, while a combined proxy (the total CRI score) showed a positive relationship with the volume of left middle temporal gyrus and inferior parietal lobule, and pars orbitalis in the right hemisphere.

Discussion

These results might indicate that more complex occupational activities and overall more intellectually and socially active life-style could contribute to better brain health, especially in regions known to be more vulnerable to Alzheimer's disease.

Extraneous Load, Patient Census, and Patient Acuity Correlate With Cognitive Load During ICU Rounds

BACKGROUND

Cognitive load theory asserts that learning and performance degrade when cognitive load exceeds working memory capacity. This is particularly relevant in the learning environment of ICU rounds, when multidisciplinary providers integrate complex decision-making and teaching in a noisy, high-stress environment prone to cognitive distractions.

RESEARCH QUESTION

What features of ICU rounds correlate with high provider cognitive load?

STUDY DESIGN AND METHODS

This was an observational, multisite study of multidisciplinary providers during ICU rounds. Investigators recorded rounding characteristics and hourly extraneous cognitive load events during rounds (defined as distractions, episodes of split-attention or repetition, and deviations from standard communication format). After rounds, investigators measured each provider's cognitive load using the provider task load (PTL), an instrument derived from the National Aeronautics and Space Administration Task Load Index survey that assesses perceived workload associated with complex tasks. Relationships between rounding characteristics, extraneous load, and PTL score were evaluated using mixed-effects modeling.

RESULTS

A total of 76 providers were observed during 32 rounds from December 2020 to May 2021. The mean rounding census ± SD was 12.5 ± 2.9 patients. The mean rounding time ± SD was 2 h 17 min ± 49 min. The mean extraneous load ± SD was 20.5 ± 4.5 events per hour, or one event every 2 min 51 s. This included 8.6 ± 3.4 distractions, 8.2 ± 4.2 communication deviations, 1.9 ± 1.4 repetitions, and 1.8 ± 1.3 episodes of split-attention per hour. Controlling for covariates, the hourly extraneous load events, number of new patients, and number of higher acuity patients were each associated with increased PTL score (slope, 2.40; 95% CI, 0.76-4.04; slope, 5.23; 95% CI, 2.02-8.43; slope, 3.35; 95% CI, 1.34-5.35, respectively).

INTERPRETATION

Increased extraneous load, new patients, and patient acuity were associated with higher cognitive load during ICU rounds. These results can help direct how the ICU rounding structure may be modified to reduce workload and optimize provider learning and performance.

The role of cognitive reserve in traumatic brain injury: a systematic review of observational studies

OBJECTIVE

Evaluate the role of cognitive reserve (CR) on cognitive and physical sequelae in traumatic brain injury (TBI).

METHODS

A comprehensive search strategy was conducted in four databases in English and Spanish in the last 12 years (2011-2023). Inclusion criteria: original cross-sectional and longitudinal studies whose main or secondary objective was to evaluate the effect of CR in adult patients with TBI. PRISMA guidelines were used to report the search and selection method and STROBE checklist was used to evaluate the quality of studies.

RESULTS

Eighteen observational studies were included in this review. Multiple sources of variability were observed: number of patients, time of evolution, severity of the TBI, type of CR proxy, cognitive assessment instrument, etc. However, the most commonly used indicators of CR were premorbid IQ and educational attainment. A positive and consistent association between CR and performance on cognitive tests after injury was found.

CONCLUSIONS

CR has a consistent positive effect on cognition and on some other aspects of recovery in traumatic brain injury. In future studies, it will be necessary to promote the use of CR indices based on various indicators and explore the effects of CR on other aspects related to the recovery of brain trauma.

How long have you exercised in your life? The effect of motor reserve and current physical activity on cognitive performance

OBJECTIVES

Aging of the population encourages research on how to preserve cognition and quality of life. Many studies have shown that Physical Activity (PA) positively affects cognition in older adults. However, PA carried out throughout the individual's lifespan may also have an impact on cognition in old age. We hypothesize the existence of Motor Reserve (MR), a flexible and dynamic construct that increases over time and compensates for age-related motor and cognitive loss.

METHODS

Two questionnaires were developed and validated to estimate MR (Physical Activity carried out throughout the individual's lifespan) and Current Physical Activity (CPA, PA carried out in the previous 12 months). They were administered to 75 healthy individuals over 50 to verify the relation with cognition. MR and CPA include physical exercise (i.e., structured activities to improve or maintain physical fitness) and incidental PA, which we consider as any movement that leads to a metabolic cost above baseline (e.g., housekeeping, walking). In addition, the Cognitive Reserve Index questionnaire (CRI), a reliable predictor of cognitive performance, was used to measure each participant's Cognitive Reserve.

RESULTS

The factors that most influenced performance are Age and Cognitive Reserve, but also MR and CPA together and MR when it is the only factor.

CONCLUSIONS

Cognitive variability in adult and elderly populations is explained by both MR and CPA. PA training could profitably be included in new preventive and existing interventions.

The Mediating Role of Cortical Atrophy on the Relationship between the Resilience Index and Cognitive Function: Findings from the Healthy Brain Initiative

Background

Lifestyle factors are linked to differences in brain aging and risk for Alzheimer's disease, underscored by concepts like 'cognitive reserve' and 'brain maintenance'. The Resilience Index (RI), a composite of 6 factors (cognitive reserve, physical and cognitive activities, social engagement, diet, and mindfulness) provides such a holistic measure.

Objective

This study aims to examine the association of RI scores with cognitive function and assess the mediating role of cortical atrophy.

Methods

Baseline data from 113 participants (aged 45+, 68% female) from the Healthy Brain Initiative were included. Life course resilience was estimated with the RI, cognitive performance with Cognivue®, and brain health using a machine learning derived Cortical Atrophy Score (CAS). Mediation analysis probed the relationship between RI, cognitive outcomes, and cortical atrophy.

Results

In age and sex adjusted models, the RI was significantly associated with CAS (β= -0.25, p = 0.006) and Cognivue® scores (β= 0.32, p < 0.001). The RI-Cognivue® association was partially mediated by CAS (β= 0.07; 95% CI [0.02, 0.14]).

Conclusions

Findings revealed that the collective effect of early and late-life lifestyle resilience factors on cognition are partially explained by their association with less brain atrophy. These findings underscore the value of comprehensive lifestyle assessments in understanding the risk and progression of cognitive decline and Alzheimer's disease in an aging population.

A bidirectional relationship between cognitive reserve and cognition among older adults in a rural Chinese community: a cross-lagged design

Background

The concept of cognitive reserve (CR) plays a crucial role in understanding cognitive aging and resilience. Accumulating evidence revealed the influence of CR proxy on cognitive function, but it remains unknown whether a reverse association or reciprocal effect exists.

Objective

The aim of this study is to observe the bidirectional relationship between cognitive reserve proxies and cognitive function among older adults in rural Chinese communities, providing a better understanding of the underlying mechanisms and potential moderating factors involved.

Method

This longitudinal study analyzed 792 older adults (70.23 ± 5.87 years; 59.8%female) aged 60 years and older from the health status of rural older adults (HSRO) study over a 3-year period. Cognition was assessed by the Mini-Mental State Examination (MMSE). Cross-lagged panel modeling was utilized to analyze the interrelationship between cognitive reserve proxies and cognitive performance. Additionally, latent profile analysis was employed to identify different subtypes of neuropathic load within the study population.

Results

Our cross-lagged analyses revealed significant associations between CR at T0 and MMSE scores at T1 (β = 0.81), as well as between MMSE scores at T0 and CR at T1 (β = 0.04). However, when conducting stratified analyses, we found no significant lagged relationships among individuals with high neuropathic load or those at an advanced age (p > 0.05). Furthermore, our longitudinal comparisons indicated changes in the contribution of CR proxy factors over time.

Conclusion

The findings suggested a bidirectional relationship between cognitive reserve and cognitive performance in older adults. These results emphasized the importance of implementing timely public health measures to enhance cognitive reserve and cognitive performance ultimately promoting healthier aging among older adults.

Validation of the Cognitive Reserve Index Questionnaire (CRIq) in Arabic

Cognitive reserve is the adaptability of cognitive processes in the face of brain aging and pathology. This study aimed to validate the Arabic version of the Cognitive Reserve Index Questionnaire (CRIq) in a healthy Lebanese sample. CRIq assesses cognitive reserve through three domains: education, working activity, and leisure time. Statistical measures, including descriptive and regression analysis along with structural equation modeling, were utilized to investigate the convergent and discriminant validity of the CRIq, incorporating fluid intelligence (Gf) and measures of cognitive function, long-term memory encoding and retrieval (Glr), and processing speed (Gs). Results from 174 participants revealed that the activities assessed by the CRIq-Arabic were comparable to the original CRIq study, with slight cultural differences. The internal consistency of the CRIq-Arabic was good (Cronbach's α = 0.88), indicating reliability. Convergent validity was confirmed, with moderate to high loadings on the cognitive reserve latent construct. Discriminant validity was supported as correlations between cognitive reserve variables and non-target constructs (Gf, Glr, and Gs) were less than 1. The findings provide an initial psychometric validation of the CRIq-Arabic. Further research of clinical samples is needed to enhance its utility in neuropsychological practice.

Physical activity, biomarkers of brain pathologies and dementia risk: Results from the Memento clinical cohort

INTRODUCTION

This study aims to examine whether physical activity moderates the association between biomarkers of brain pathologies and dementia risk.

METHODS

From the Memento cohort, we analyzed 1044 patients with mild cognitive impairment, aged 60 and older. Self-reported physical activity was assessed using the International Physical Activity Questionnaire. Biomarkers of brain pathologies comprised medial temporal lobe atrophy (MTA), white matter lesions, and plasma amyloid beta (Aβ)42/40 and phosphorylated tau181. Association between physical activity and risk of developing dementia over 5 years of follow-up, and interactions with biomarkers of brain pathologies were tested.

RESULTS

Physical activity moderated the association between MTA and plasma Aβ42/40 level and increased dementia risk. Compared to participants with low physical activity, associations of both MTA and plasma Aβ42/40 on dementia risk were attenuated in participants with high physical activity.

DISCUSSION

Although reverse causality cannot be excluded, this work suggests that physical activity may contribute to cognitive reserve.

HIGHLIGHTS

Physical activity is an interesting modifiable target for dementia prevention. Physical activity may moderate the impact of brain pathology on dementia risk. Medial temporal lobe atrophy and plasma amyloid beta 42/40 ratio were associated with increased dementia risk especially in those with low level of physical activity.

Effects of Physical Activity on Cognitive Functioning: The Role of Cognitive Reserve and Active Aging

BACKGROUND

The increase in average life expectancy necessitates the identification of possible mechanisms capable of promoting "active aging" to ensure adequate levels of global functioning. Numerous studies show that regular physical activity promotes, even in the elderly, a state of functional psychophysical well-being capable of slowing down age-related cognitive decline. This study aimed to clarify whether, and how, the intensity of physical activity can modulate cognitive and executive skills by influencing specific psychological variables.

METHODS

Our sample consisted of 151 senior subjects divided into hikers (HIK), gentle gymnastics (GYM), and sedentary (SED), who practice intense, moderate, and reduced physical activity, respectively. A battery of psychological questionnaires was administrated to evaluate attentional skills, decision-making, the ability to implement targeted behaviors, perceived self-efficacy, and psychophysical well-being. We included: the Mini-Mental State Examination, Cognitive Reserve Index Questionnaire, General Self-Efficacy Scale, Letter Cancellation Test, Everyday Competence Questionnaire, and Geriatric Depression Scale (GDS).

RESULTS

Comparisons between the scores reported by the three groups showed that the HIK group differs from the others with respect to most of the measurements, presenting better mood and cognitive performance, and a specific psychological profile. On the contrary, the GYM group appeared to have a greater affinity with the SED group than with the HIK group, both cognitively and psychologically.

CONCLUSIONS

Types of physical activity, as well as the intensity and frequency with which they are practiced, are factors that promote an active aging process, protecting the psychophysical well-being and overall cognitive functioning of the elderly.

Do cognitive reserve and executive functions matter to perform the reading the mind in the eyes test in late lifespan?

Theory of Mind (ToM) is the capacity to understand the feelings and emotional states (i.e., affective ToM) or intentions, goals, and beliefs (i.e., cognitive ToM) of others. Previous evidence on the effect of executive functions and educational attainment on affective ToM is controversial. This study was conducted to investigate: (1) the nature of the associations between affective ToM and some indexes of cognitive reserve (i.e., years of education, vocabulary) in late adulthood when age was controlled; (2) whether cognitive reserve (e.g., years of education, leisure activities, vocabulary) and age predicted affective ToM in late adulthood; (3) the associations between affective ToM and some executive functions measures in late adulthood, controlling for the effect of age; (4) whether executive functioning predicted affective ToM performance; (5) whether some executive functions (i.e., cognitive flexibility and inhibition) mediated between vocabulary score (i.e., used as an index of cognitive reserve) and affective ToM score. Fifty-six 75-93-year-old community-dwellers completed a battery of tasks to assess some executive functions and affective ToM skills (i.e., through the Reading the Mind in the Eyes Test). It was found that vocabulary, age, and participation in outdoor socio-recreational leisure activities predicted 31% of the variance in the Reading the Mind in the Eyes condition. Moreover, significant relationships were found between ToM and some executive functions, that is, cognitive flexibility and inhibition predicted 34% of the ToM score. Finally, cognitive flexibility and inhibition mediate between cognitive reserve (i.e., assessed in terms of vocabulary) and Reading the Mind in the Eyes test score.

Digital Device Use, Risk of Cognitive Impairment, and Cognition in Healthy Older Adults: The Role of Cognitive Reserve

Neuroprotective factors are essential to successful ageing. As such, digital device use was proposed as an easily accessible and stimulating available cognitive activity to enhance brain function. Nonetheless, there was a lack of studies inspecting the connection between digital device use and cognitive reserve, the risk of cognitive impairment, and cognition. This study aims to investigate the potential mediator and moderator of the association between digital device use, cognitive reserve, the risk of cognitive impairment, and cognition among healthy older adults. A quantitative cross-sectional study was conducted to investigate the relationship between digital device use and cognitive reserve, the risk of cognitive impairment, and cognition. A total of 210 healthy older adults were recruited through purposive sampling. The results obtained from this study revealed that there was a significant difference in cognitive reserve and cognition between healthy older adults who use a digital device for communication purpose only and who use a digital device for multiple purposes. A significant relationship was also found between cognitive reserve, the risk of cognitive impairment, and cognition. Although digital device use was found to be significantly associated with cognitive reserve and cognition, it was not significantly associated with the risk of cognitive impairment. Cognitive reserve partially mediated the relationship between digital device use and cognition, supporting the notion that cognitive reserve acts as an underlying mechanism in the relationship between digital device use and cognition. Hence, digital device use was suggested to be a good daily intervention for healthy older adults to build on their cognitive reserve and potentially protect their cognition from declining. Nevertheless, relying on digital device use alone is not sufficient, and other activities should be explored to enhance cognitive reserve among healthy older adults.

The Role of Cognition in Divergent Thinking: Implications for Successful Aging

Promoting active and successful aging has become crucial to improve quality of life in later adulthood and reduce the impact of cognitive decline. Increasing evidence suggested that the ability to think creatively (e.g., via divergent thinking), similar to cognitive reserve, could represent a beneficial factor against the negative effects of aging. However, there is still little evidence investigating the relationships between divergent thinking, cognitive functions, and cognitive reserve in late adulthood. The present study explored these relationships in a sample of 98 individuals ranging from 61 to 88 years old (mean age: 72.44 ± 6.35). Results showed that visual, but not verbal, divergent thinking was affected by aging. Interestingly, visual divergent thinking performance was predicted by both the cognitive component of crystallized intelligence and cognitive reserve. Only the crystallized component of intelligence was found to mediate the aging effect on visual divergent thinking performance. These results suggest that in later adulthood a potential shift strategy to prior knowledge and semantic components over executive and control components of cognition could underlie a preserved ability to think divergently and, plausibly, creatively. Limitations of the study and implications for successful aging are discussed.

In person versus remote cognitive rehabilitation in patients with subjective cognitive decline or neurocognitive disorders: what factors drive patient's preference?

Background

To date, there is still a lack of consensus for identifying the ideal candidate for cognitive telerehabilitation (TR). The main goal of the present study is to identify the factors associated to the preference for either TR or in-person cognitive training (CT) programs in older adults at risk of dementia or with early cognitive impairment.

Methods

A sample of 56 participants with subjective cognitive decline or neurocognitive disorders eligible for CT were enrolled at the Dementia Research Center and Neurorehabilitation Unit of IRCCS Mondino Foundation. All individuals underwent a baseline assessment to capture their complete profile, including cognitive reserve and lifestyle habits, sociodemographic characteristics, cognitive functioning, and mental health. Patients were then asked their preference for TR or in-person CT, before being randomized to either treatment as per protocol procedures. Statistical analyses included explorative descriptive approach, logistic regression, and non-parametric models to explore the overall contribution of each variable.

Results

The two (TR and in-person) preference groups were similar for cognitive functioning and mental health status. Socio-demographic and lifestyle profiles seem to be the most important factors to influence the preference in terms of the area under the curve (AUC) of the models. The two preference groups differed in terms of socio-demographic characteristics (e.g., level of technological skills, age, and distance from the clinic). Furthermore, participants who selected the TR modality of CT had significantly higher levels of cognitive reserve and adopted more protective lifestyle habits (e.g., regular physical activity, Mediterranean diet) when compared to those who preferred in-person CT.

Discussion

These findings highlight that the preference to receive CT delivered by TR or in person is a complex issue and is influenced by a variety of factors, mostly related to lifestyle habits and sociodemographic characteristics. Availability of profiles of patients that may be more attracted to one or the other modality of TR may help promote shared decision-making to enhance patient experience and outcomes.

Effect of cognitive reserve on the association between slow wave sleep and cognition in community-dwelling older adults

Sleep, especially slow wave sleep (SWS), is essential for cognitive functioning and is reduced in aging. The impact of sleep quality on cognition is variable, especially in aging. Cognitive reserve (CR) may be an important modulator of these effects. We aimed at investigating this question to better identify individuals in whom sleep disturbances might have greater behavioral consequences. Polysomnography and neuropsychological assessments were performed in 135 cognitively intact older adults (mean age ± SD: 69.4 ± 3.8y) from the Age-Well randomized controlled trial (baseline data). Two measures of cognitive engagement throughout life were used as CR proxies. Linear regression analyses were performed between the proportion of SWS, and executive function and episodic memory composite scores. Then, interaction analyses between SWS and CR proxies on cognition were conducted to assess the possible impact of CR on these links. SWS was positively associated with episodic memory, but not with executive function. CR proxies modulated the associations between SWS and both executive and episodic memory performance. Specifically, individuals with higher CR were able to maintain cognitive performance despite low amounts of SWS. This study provides the first evidence that CR may protect against the deleterious effects of age-related sleep changes on cognition.

The Spectrum of Cognitive Dysfunction in Amyotrophic Lateral Sclerosis: An Update

Cognitive dysfunction is an important non-motor symptom in amyotrophic lateral sclerosis (ALS) that has a negative impact on survival and caregiver burden. It shows a wide spectrum ranging from subjective cognitive decline to frontotemporal dementia (FTD) and covers various cognitive domains, mainly executive/attention, language and verbal memory deficits. The frequency of cognitive impairment across the different ALS phenotypes ranges from 30% to 75%, with up to 45% fulfilling the criteria of FTD. Significant genetic, clinical, and pathological heterogeneity reflects deficits in various cognitive domains. Modern neuroimaging studies revealed frontotemporal degeneration and widespread involvement of limbic and white matter systems, with hypometabolism of the relevant areas. Morphological substrates are frontotemporal and hippocampal atrophy with synaptic loss, associated with TDP-43 and other co-pathologies, including tau deposition. Widespread functional disruptions of motor and extramotor networks, as well as of frontoparietal, frontostriatal and other connectivities, are markers for cognitive deficits in ALS. Cognitive reserve may moderate the effect of brain damage but is not protective against cognitive decline. The natural history of cognitive dysfunction in ALS and its relationship to FTD are not fully understood, although there is an overlap between the ALS variants and ALS-related frontotemporal syndromes, suggesting a differential vulnerability of motor and non-motor networks. An assessment of risks or the early detection of brain connectivity signatures before structural changes may be helpful in investigating the pathophysiological mechanisms of cognitive impairment in ALS, which might even serve as novel targets for effective disease-modifying therapies.

Evidence Accumulation Rate Moderates the Relationship between Enriched Environment Exposure and Age-Related Response Speed Declines

Older adults exposed to enriched environments (EEs) maintain relatively higher levels of cognitive function, even in the face of compromised markers of brain health. Response speed (RS) is often used as a simple proxy to measure the preservation of global cognitive function in older adults. However, it is unknown which specific selection, decision, and/or motor processes provide the most specific indices of neurocognitive health. Here, using a simple decision task with electroencephalography (EEG), we found that the efficiency with which an individual accumulates sensory evidence was a critical determinant of the extent to which RS was preserved in older adults (63% female, 37% male). Moreover, the mitigating influence of EE on age-related RS declines was most pronounced when evidence accumulation rates were shallowest. These results suggest that the phenomenon of cognitive reserve, whereby high EE individuals can better tolerate suboptimal brain health to facilitate the preservation of cognitive function, is not just applicable to neuroanatomical indicators of brain aging but can be observed in markers of neurophysiology. Our results suggest that EEG metrics of evidence accumulation may index neurocognitive vulnerability of the aging brain.Significance Statement Response speed in older adults is closely linked with trajectories of cognitive aging. Here, by recording brain activity while individuals perform a simple computer task, we identify a neural metric that is a critical determinant of response speed. Older adults exposed to greater cognitive and social stimulation throughout a lifetime could maintain faster responding, even when this neural metric was impaired. This work suggests EEG is a useful technique for interrogating how a lifetime of stimulation benefits brain health in aging.

Design and Harmonization Approach for the Multi-Institutional Neurocognitive Discovery Study (MINDS) of Adult Congenital Heart Disease (ACHD) Neuroimaging Ancillary Study: A Technical Note

Dramatic advances in the management of congenital heart disease (CHD) have improved survival to adulthood from less than 10% in the 1960s to over 90% in the current era, such that adult CHD (ACHD) patients now outnumber their pediatric counterparts. ACHD patients demonstrate domain-specific neurocognitive deficits associated with reduced quality of life that include deficits in educational attainment and social interaction. Our hypothesis is that ACHD patients exhibit vascular brain injury and structural/physiological brain alterations that are predictive of specific neurocognitive deficits modified by behavioral and environmental enrichment proxies of cognitive reserve (e.g., level of education and lifestyle/social habits). This technical note describes an ancillary study to the National Heart, Lung, and Blood Institute (NHLBI)-funded Pediatric Heart Network (PHN) "Multi-Institutional Neurocognitive Discovery Study (MINDS) in Adult Congenital Heart Disease (ACHD)". Leveraging clinical, neuropsychological, and biospecimen data from the parent study, our study will provide structural-physiological correlates of neurocognitive outcomes, representing the first multi-center neuroimaging initiative to be performed in ACHD patients. Limitations of the study include recruitment challenges inherent to an ancillary study, implantable cardiac devices, and harmonization of neuroimaging biomarkers. Results from this research will help shape the care of ACHD patients and further our understanding of the interplay between brain injury and cognitive reserve.

The indirect effect of cognitive reserve on the relationship between age and cognition in pathological ageing: A cross-sectional retrospective study in an unselected and consecutively enrolled sample

Cognitive reserve (CR) allows individuals to maintain cognitive functionality even in the presence of pathologies. The compensation hypothesis suggests that CR plays an indirect role between age and cognitive decline, contrasting the negative effect of ageing on cognition. We test this hypothesis in an unselected and consecutively enrolled sample of memory clinic attendees (n = 134) who completed the CR Index questionnaire and three neuropsychological tests assessing global cognition (MMSE, FAB, CDT). Participants were divided into two groups based on standard diagnostic criteria (DSM-5): those who were cognitively impaired (n = 92) and those who were preserved (n = 42). A principal component analysis was used to extract a composite measure of global cognitive functioning from the three neuropsychological tests, and mediation analysis was used to examine the relationship between CR, age and global cognitive functioning in the two groups. Results revealed that: (i) age had a significant direct negative effect on the global cognitive score in both groups; (ii) the three socio-behavioural proxies of CR together suppress the direct negative relationship between age and global cognitive score in cognitively impaired patients but not in cognitively preserved participants. This study confirms the association between CR, age and cognition and allows us to validate its role in a population with cognitive impairment and extend findings to a low-to-middle educated population. These results hold important implications for public health and wellness promotion, emphasising the beneficial role of maintaining healthy and active physical, cognitive and social lifestyles.

Impact of educational attainment on time to cognitive decline among marginalized older adults: Cohort study of 20,311 adults

BACKGROUND

The effect of years of education on the maintenance of healthy cognitive functioning may differ by race and ethnicity given historical and ongoing inequities in educational quality.

METHODS

We examined 20,311 Black, Latinx, and White adults aged 51-100 from the Health and Retirement Study (2008-2016). Telephone Interview for Cognitive Status-27 data was used to measure cognitive functioning. Generalized additive mixed models were stratified by race and ethnicity and educational attainment (≥12 vs. <12 years). Selected social determinants of health, all-cause mortality, time-varying health and healthcare utilization characteristics, and study wave were included as covariates.

RESULTS

On average, Black and Latinx adults scored lower at baseline compared to White adults regardless of educational attainment (p < 0.001), with a significant overlap in the distributions of scores. The rate of cognitive decline was non-linear for Black, Latinx, and White adults (p < 0.001), and a period of stability was witnessed for those with higher educational attainment irrespective of race and ethnicity. Compared to Black, Latinx, and White adults with lower educational attainment, higher-educated White adults received the greatest protection from cognitive decline (13 years; 64 vs. 51), followed by Latinx (12 years; 67 vs. 55), and Black adults (10 years; 61 vs. 51). Latinx adults experienced cognitive decline beginning at a later age.

CONCLUSIONS

The extent to which higher educational attainment protects adults from cognitive decline differs by race and ethnicity, such that higher-educated White adults received a greater benefit than higher-educated Black or Latinx adults.

Relationship between cognitive reserve, brain volume, and neuropsychological performance in amnestic and nonamnestic MCI

Cognitive Reserve (CR) is a theoretical construct that influences the onset and course of cognitive and structural changes that occur with aging and mild cognitive impairment (MCI). There is a paucity of research that examines the relationship of CR and brain volumes in amnestic (aMCI) and nonamnestic (naMCI) separately. This study is a retrospective chart review of MCI patients who underwent neuropsychological evaluation and brain MRI with NeuroReader™ (NR). NR is an FDA-cleared software that standardizes MRI volumes to a control sample. Classifications of aMCI and naMCI were based on Petersen criteria. CR was measured as education, occupation, and word reading. Data analysis included bivariate correlations between CR, neuropsychological test scores, and NR-brain volumes by MCI subtype. The Benjamini-Hochberg method corrected for multiple comparisons. The sample included 91 participants with aMCI and 41 with naMCI. Within naMCI, positive correlations were observed between CR and whole brain volume, total gray matter, bifrontal, left parietal, left occipital, and bilateral cerebellum. Within aMCI, no significant correlations were observed between CR and brain volumes. Positive correlations with CR were observed in language, attention, and visual learning in both aMCI and naMCI groups. The current study adds to the minimal literature on CR and naMCI. Results revealed that CR is associated with volumetrics in naMCI only, though cognitive findings were similar in both MCI groups. Possible explanations include heterogeneous disease pathologies, disease stage, or a differential influence of CR on volumetrics in MCI. Additional longitudinal and biomarker studies will better elucidate this relationship.