Declarative Learning, Priming, and Procedural Learning Performances comparing Individuals with Amnestic Mild Cognitive Impairment, and Cognitively Unimpaired Older Adults.

OBJECTIVE: While declarative learning is dependent on the hippocampus, procedural learning and repetition priming can operate independently from the hippocampus, making them potential targets for behavioral interventions that utilize non-declarative memory systems to compensate for the declarative learning deficits associated with hippocampal insult. Few studies have assessed procedural learning and repetition priming in individuals with amnestic mild cognitive impairment (aMCI). METHOD: This study offers an overview across declarative, conceptual repetition priming, and procedural learning tasks by providing between-group effect sizes and Bayes Factors (BFs) comparing individuals with aMCI and controls. Seventy-six individuals with aMCI and 83 cognitively unimpaired controls were assessed. We hypothesized to see the largest differences between individuals with aMCI and controls on declarative learning, followed by conceptual repetition priming, with the smallest differences on procedural learning. RESULTS: Consistent with our hypotheses, we found large differences between groups with supporting BFs on declarative learning. For conceptual repetition priming, we found a small-to-moderate between-group effect size and a non-conclusive BF somewhat in favor of a difference between groups. We found more variable but overall trivial differences on procedural learning tasks, with inconclusive BFs, in line with expectations. CONCLUSIONS: The current results suggest that conceptual repetition priming does not remain intact in individuals with aMCI while procedural learning may remain intact. While additional studies are needed, our results contribute to the evidence-base that suggests that procedural learning may remain spared in aMCI and helps inform behavioral interventions that aim to utilize procedural learning in this population.

Health concerns and attitudes towards research participation in a community of rural Black Americans.

OBJECTIVES: Describe health concerns of Black Americans as they age and what influences their participation in aging and clinical research. METHODS: Fifty participants attended focus groups and completed questionnaires to identify barriers to research participation and attitudes toward dementia screening. Bivariate correlations explored associations between barriers to research participation and attitudes toward dementia screening. RESULTS: Cancer, hereditary conditions, vascular conditions, memory disorders, and psychological disorders were the greatest health concerns. Time demands, mistrust, lack of knowledge about potential research, and stigma were identified as barriers for research participation. Incentives, better understanding of how proposed research will benefit the community, lifestyle modification studies, active presence of principal researchers/clinicians, and community investment were identified as factors to improve participation. Questionnaires revealed mistrust and religious beliefs to be among the primary barriers. Attitudes toward dementia screening reflected perceived stigma, suffering, and subsequent loss of independence. Higher barriers to participation were associated with perceived stigma and loss of independence related to dementia screening. CONCLUSIONS: Successfully recruiting Black Americans for aging and clinical research remains a challenge. This study identifies barriers to participation and offers suggestions for planning and recruitment.

Procedural learning, declarative learning, and working memory as predictors of learning the use of a memory compensation tool in persons with amnestic mild cognitive impairment.

Persons with amnestic Mild Cognitive Impairment (aMCI) are at risk for experiencing changes in their daily functioning due to their memory impairment. The Memory Support System (MSS), a compensatory calendaring system, was developed to support functional independence in persons with aMCI (pwaMCI). This cross-sectional study examined procedural learning, declarative learning, and working memory as predictors of MSS learning efficiency in pwaMCI. Sixty pwaMCI participated in MSS training. The Serial Reaction Time Test and Mirror Tracing Test were used to assess procedural learning. The Rey Auditory Verbal Learning Test and CogState One Card Learning were used to assess declarative learning and the CogState One Back task was used to assess working memory. Multiple regression analyses were conducted to assess if procedural learning, declarative learning, and working memory predicted MSS learning efficiency. This study showed that declarative learning predicted MSS learning efficiency in pwaMCI, with less consistent results for procedural learning and non-significant results for working memory. Findings suggest that success in teaching compensatory tools is greater when training is offered in early aMCI before declarative learning skill is fully lost. Future studies should assess additional strategies to facilitate MSS learning in advanced aMCI.

Hippocampal Subfields in Mild Cognitive Impairment: Associations with Objective and Informant-Report of Memory Function.

BACKGROUND: Evidence suggests that select hippocampal subfields are implicated in the initial stages of Alzheimer's disease (AD) and are selectively involved in objective memory. Less is known whether subfields are associated with informant-reported memory difficulties of individuals with a diagnosis of mild cognitive impairment (MCI). METHOD: Data from 56 participants with a diagnosis of amnestic MCI were included in the present study. To test whether FreeSurfer derived hippocampal subfields (CA1-4, subiculum, presubiculum, and dentate gyrus) were associated with objective (learning and delayed recall) and informant-reports of memory difficulties, we used multiple linear regression analysis. Subfields were adjusted for total intracranial volume, and age, sex, and years of education were included as covariates in all models. RESULTS: Larger presubiculum, subiculum, and CA4/dentate gyrus volumes were associated with higher delayed recall scores, and larger subiculum and CA4/dentate gyrus volumes were associated with fewer informant-reports of memory difficulties. There were no statistically significant associations between subfields and learning scores. DISCUSSION: Findings from the present study support the idea that difficulties with memory-dependent everyday tasks in older adults with MCI may signal a neurodegenerative process while increasing understanding of subfields correlates of these memory-specific functional difficulties. Continued investigations into identifying patterns of subfield atrophy in AD may aid early identification of those at higher risk of dementia conversion while advancing precision medicine.

Behavioral Interventions in Mild Cognitive Impairment (MCI): Lessons from a Multicomponent Program.

Comparative effectiveness of behavioral interventions to mitigate the impacts of degeneration-based cognitive decline is not well understood. To better address this gap, we summarize the studies from the Healthy Action to Benefit Independence & Thinking (HABIT®) program, developed for persons with mild cognitive impairment (pwMCI) and their partners. HABIT® includes memory compensation training, computerized cognitive training (CCT), yoga, patient and partner support groups, and wellness education. Studies cited include (i) a survey of clinical program completers to establish outcome priorities; (ii) a five-arm, multi-site cluster randomized, comparative effectiveness trial; (iii) and a three-arm ancillary study. PwMCI quality of life (QoL) was considered a high-priority outcome. Across datasets, findings suggest that quality of life was most affected in groups where wellness education was included and CCT withheld. Wellness education also had greater impact on mood than CCT. Yoga had a greater impact on memory-dependent functional status than support groups. Yoga was associated with better functional status and improved caregiver burden relative to wellness education. CCT had the greatest impact on cognition compared to yoga. Taken together, comparisons of groups of program components suggest that knowledge-based interventions like wellness education benefit patient well-being (e.g., QoL and mood). Skill-based interventions like yoga and memory compensation training aid the maintenance of functional status. Notably, better adherence produced better outcomes. Future personalized intervention approaches for pwMCI may include different combinations of behavioral strategies selected to optimize outcomes prioritized by patient values and preferences.

Cross-national harmonization of cognitive measures across HRS HCAP (USA) and LASI-DAD (India).

BACKGROUND: As global populations age, cross-national comparisons of cognitive health and dementia risk are increasingly valuable. It remains unclear, however, whether country-level differences in cognitive function are attributable to population differences or bias due to incommensurate measurement. To demonstrate an effective method for cross-national comparison studies, we aimed to statistically harmonize measures of episodic memory and language function across two population-based cohorts of older adults in the United States (HRS HCAP) and India (LASI-DAD). METHODS: Data for 3,496 HRS HCAP (≥65 years) and 3,152 LASI-DAD (≥60 years) participants were statistically harmonized for episodic memory and language performance using confirmatory factor analysis (CFA) methods. Episodic memory and language factor variables were investigated for differential item functioning (DIF) and precision. RESULTS: CFA models estimating episodic memory and language domains based on a priori adjudication of comparable items fit the data well. DIF analyses revealed that four out of ten episodic memory items and five out of twelve language items measured the underlying construct comparably across samples. DIF-modified episodic memory and language factor scores showed comparable patterns of precision across the range of the latent trait for each sample. CONCLUSIONS: Harmonization of cognitive measures will facilitate future investigation of cross-national differences in cognitive performance and differential effects of risk factors, policies, and treatments, reducing study-level measurement and administrative influences. As international aging studies become more widely available, advanced statistical methods such as those described in this study will become increasingly central to making universal generalizations and drawing valid conclusions about cognitive aging of the global population.

Repetition Priming in Individuals with Amnestic Mild Cognitive Impairment and Alzheimer's Dementia: a Systematic Review and Meta-Analysis.

The literature on repetition priming in Alzheimer's disease (AD) is inconsistent, with some findings supporting spared priming while others do not. Several factors may explain these inconsistencies, including AD severity (e.g., dementia vs. Mild Cognitive Impairment; MCI) and priming paradigm-related characteristics. This systematic review and meta-analysis provides a quantitative summary of repetition priming in AD. We examined the between-group standard mean difference comparing repetition priming in AD dementia or amnestic MCI (aMCI; presumably due to AD) to controls. Thirty-two studies were selected, including 590 individuals with AD dementia, 267 individuals with amnestic MCI, and 703 controls. Our results indicated that both individuals with aMCI and AD dementia perform worse on repetition priming tasks than cognitively older adults. Paradigm-related moderators suggested that the effect size between studies comparing the combined aMCI or AD dementia group to cognitively healthy older adults was the highest for paradigms that required participants to produce, rather than identify, primes during the test phase. Our results further suggested that priming in AD is impaired for both conceptual and perceptual priming tasks. Lastly, while our results suggested that priming in AD is impaired for priming tasks that require deep processing, we were unable to draw firm conclusions about whether priming is less impaired in aMCI or AD dementia for paradigms that require shallow processing.

Latent Factor Structure of Outcome Measures Used in the HABIT® Mild Cognitive Impairment Intervention Programs.

BACKGROUND: In Alzheimer's disease and related disorders (ADRD) research, common outcome measures include cognitive and functional impairment, as well as persons with mild cognitive impairment (pwMCI) and care partner self-reported mood and quality of life. Studies commonly analyze these measures separately, which potentially leads to issues of multiple comparisons and/or multicollinearity among measures while ignoring the latent constructs they may be measuring. OBJECTIVE: This study sought to examine the latent factor structure of a battery of 12-13 measures of domains mentioned above, used in a multicomponent behavioral intervention (The HABIT® program) for pwMCI and their partners. METHODS: Exploratory factor analysis (EFA) involved 214 pwMCI-partner pairs. Subsequent Confirmatory factor analyses (CFA) used 730 pairs in both pre- and post-intervention conditions. RESULTS: EFA generated a three-factor model. Factors could be characterized as partner adjustment (29.9%), pwMCI adjustment (18.1%), and pwMCI impairment (12.8%). The subsequent CFA confirmed our findings, and the goodness-of-fit for this model was adequate in both the pre- (CFI = 0.937; RMSEA = 0.057, p = 0.089) and post-intervention (CFI = 0.942; RMSEA = 0.051, p = 0.430) groups. CONCLUSION: Results demonstrated a stable factor structure across cohorts and intervention conditions suggesting that three broad factors may provide a straightforward and meaningful model to assess intervention outcome, at least during the MCI phase of ADRD.

Memory Support System training in mild cognitive impairment: Predictors of learning and adherence.

This study aimed to identify predictors of learning and adherence to a previously validated compensatory calendar and note-taking system (Memory Support System; MSS) in persons with amnestic mild cognitive impairment (aMCI). Age, education, global cognition, depression, and memory-related self-efficacy were studied as predictors of individuals' ability to learn the use of the MSS during the two-week training and of their adherence to the MSS 6, 12, and 18 months after training. How well an individual was able to learn the use of the MSS was itself examined as a predictor of adherence. Two-hundred-and-fifteen older adults with aMCI and their study partners (e.g., spouse, adult child) received MSS training one-hour daily for 10 days. Ordinal logistic regression analyses indicated that (1) global cognition predicted MSS learning at end of training, and (2) MSS learning at end of trainng predicted MSS adherence at 6, 12, and 18 months post-training. The current study suggests that offering compensatory strategies as early as possible for those with MCI might be of most benefit, and might have implications for long-term adherence.

Psychometric properties of the self-efficacy for managing mild cognitive impairment scale.

OBJECTIVES: We adapted a self-efficacy measure for managing chronic illness to be specific to persons with mild cognitive impairment (pwMCI). The aim of this study was to investigate the psychometric properties of the scale, the self-efficacy for managing MCI scale, for use in research. METHODS: Analyses involved data from pwMCI enrolled in a behavioral intervention study that completed the measure five times from intervention enrollment to 18-month post-intervention. Factor structure, construct validity, internal consistency, and test-retest reliability were analyzed. RESULTS: Factor analysis identified two factors, related to self-efficacy for daily activities and managing MCI, which corresponded with domains from the original chronic illness self-efficacy scale. Consistent with prior research, construct validity analysis suggested an association between memory-loss self-efficacy and psychosocial distress, but not cognitive or functional ability. Further analyses supported the scale's internal and test-retest reliability. CONCLUSIONS: Currently, no "gold standard" scale of memory-loss self-efficacy for pwMCI exists, despite the positive impact self-efficacy may have on modifiable health behaviors. Overall, results supported the notion that the scale is a valid and reliable measure of memory-loss self-efficacy for pwMCI.

Self-Efficacy Mediates the Association Between Physical Function and Perceived Quality of Life in Individuals with Mild Cognitive Impairment.

BACKGROUND: Research has shown that individuals with mild cognitive impairment (MCI) value quality of life (QoL) above and beyond cognitive function or other potential outcomes in MCI. There is evidence supporting the negative impact of poor physical function on QoL ratings. OBJECTIVE: The study explored whether a modified measure of self-efficacy for managing MCI and education mediated and/or moderated the relationship between physical function and QoL in persons with MCI. METHODS: Baseline data from 200 participants with MCI were obtained from a larger study assessing the effectiveness of a behavioral intervention. Physical function was assessed by the Short Physical Performance Battery. QoL was assessed with the Quality of Life in Alzheimer's Disease scale. Memory-related self-efficacy was assessed using a modified 9-item version of the Chronic Disease Self-Efficacy Scales. Mediation and moderation analyses tested the hypotheses that self-efficacy and education alter the association between physical function and QoL in individuals with MCI. All analyses were adjusted for age, cognitive severity, and sex. RESULTS: Self-efficacy for managing MCI was a significant mediator of the association between physical function and perceived QoL. Individuals with better physical function reported higher self-efficacy which was associated with higher QoL ratings. CONCLUSIONS: Greater self-efficacy for managing MCI mediated the negative association between physical function and quality of life in this exploratory study. Interventions aimed at enhancing memory self-efficacy in MCI may improve perceived QoL, even in the presence of poor physical function. Future research is needed to investigate this further.

Terminal decline of episodic memory and perceptual speed in a biracial population.

We compared trajectories of terminal cognitive decline in older Black (n = 3372) and White (n = 1756) persons from a defined population who completed tests of episodic memory and perceptual speed at 3-year intervals for up to 18 years. During a mean of 9.9 years of observation, 1608 Black persons and 902 White persons died. Preterminal decline of episodic memory did not differ by race. Terminal episodic memory decline began earlier in Black persons (mean of 4.3 years before death) than in White persons (mean = 3.9 years) and progressed more slowly. By contrast, terminal decline of perceptual speed began earlier in White persons (mean = 5.0 years) than in Black persons (mean = 4.5 years). Rate of perceptual speed decline was more rapid in White persons than in Black persons in both the preterminal and terminal periods. The results indicate that terminal cognitive decline occurs in Black persons but suggest that the rate of cognitive decline during the terminal period is less rapid in Black persons than in White persons.

Purpose in Life and Hospitalization for Ambulatory Care-Sensitive Conditions in Old Age.

OBJECTIVE: To test the hypothesis that higher level of purpose in life is associated with lower subsequent odds of hospitalization. DESIGN: Longitudinal cohort study. SETTING: Participants' residences in the Chicago metropolitan area. PARTICIPANTS: A total of 805 older persons who completed uniform annual clinical evaluations. MEASUREMENTS: Participants annually completed a standard self-report measure of purpose in life, a component of well-being. Hospitalization data were obtained from Part A Medicare claims records. Based on previous research, ICD-9 codes were used to identify ambulatory care-sensitive conditions (ACSCs) for which hospitalization is potentially preventable. The relation of purpose (baseline and follow-up) to hospitalization was assessed in proportional odds mixed models. RESULTS: During a mean of 4.5 years of observation, there was a total of 2,043 hospitalizations (442 with a primary ACSC diagnosis; 1,322 with a secondary ACSC diagnosis; 279 with no ACSCs). In initial analyses, higher purpose at baseline and follow-up were each associated with lower odds of more hospitalizations involving ACSCs but not hospitalizations for non-ACSCs. Results were comparable when those with low cognitive function at baseline were excluded. Adjustment for chronic medical conditions and socioeconomic status reduced but did not eliminate the association of purpose with hospitalizations involving ACSCs. CONCLUSIONS: In old age, higher level of purpose in life is associated with lower odds of subsequent hospitalizations for ambulatory care-sensitive conditions.

Change in Cognitive Abilities in Older Latinos.

The aim of this study was to compare patterns of cognitive decline in older Latinos and non-Latinos. At annual intervals for a mean of 5.7 years, older Latino (n=104) and non-Latino (n=104) persons of equivalent age, education, and race completed a battery of 17 cognitive tests from which previously established composite measures of episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability were derived. In analyses adjusted for age, sex, and education, performance declined over time in each cognitive domain, but there were no ethnic group differences in initial level of function or annual rate of decline. There was evidence of retest learning following the baseline evaluation, but neither the magnitude nor duration of the effect was related to Latino ethnicity, and eliminating the first two evaluations, during which much of retest learning occurred, did not affect ethnic group comparisons. Compared to the non-Latino group, the Latino group had more diabetes (38.5% vs. 25.0; χ2[1]=4.4; p=.037), fewer histories of smoking (24.0% vs. 39.4%, χ2[1]=5.7; p=.017), and lower childhood household socioeconomic level (-0.410 vs. -0.045, t[185.0]=3.1; p=.002), but controlling for these factors did not affect results. Trajectories of cognitive aging in different abilities are similar in Latino and non-Latino individuals of equivalent age, education, and race. (JINS, 2016, 22, 58-65).