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Objective: There is an increasing focus on understanding health disparities among various cultural groups in the United States. The need for heterogeneity in norms and test stimuli across ethnically diverse individuals are being increasingly recognized. However, to date it remains unknown whether and to what extent differences in cognitive norms and tests exist in Asian Indians, a fast-growing population in the U.S. It is essential to understand these differences to improve diagnostic accuracy and provide timely and appropriate clinical care. Method: In this study, we conducted a scoping review of available cognitive tests that were normed, developed, or adapted for Asian Indians living in the U.S. Results: The results suggested a paucity of norms and tests specifically examining cognition in this community. Conclusions: Based on the findings, we provide suggestions for research directions focusing on the development of culturally sensitive neuropsychological tools, normative data representative of this demographic, and interventions addressing healthcare access barriers. Overall, this review provides readers with relevant clinical information to immediately enhance patient care as well as provide actionable items in research to improve the future utility of neuropsychology for Asian Indians in the United States. [ABSTRACT FROM AUTHOR]

Effects of concreteness and grammatical class on lexical-semantic processing are well-documented, but the role of sensory-perceptual and sensory-motor features of concepts in underlying mechanisms producing these effects is relatively unknown. We hypothesized that processing dissimilarities in accuracy and response time performance in nouns versus verbs, concrete versus abstract words, and their interaction can be explained by differences in semantic weight--the combined amount of sensory-perceptual and sensory-motor information to conceptual representations--across those grammatical and semantic categories. We assessed performance on concrete and abstract subcategories of nouns and verbs with a semantic similarity judgment task. Results showed that when main effects of concreteness and grammatical class were analyzed in more detail, the grammatical-class effect, in which nouns are processed more accurately and quicker than verbs, was only present for concrete words, not for their abstract counterparts. Moreover, the concreteness effect, measured at different levels of abstract words, was present for both nouns and verbs, but it was less pronounced for verbs. The results do not support the grammatical-class hypothesis, in which nouns and verbs are separately organized, and instead provide evidence in favor of a unitary semantic space, in which lexical-semantic processing is influenced by the beneficial effect of sensory-perceptual and sensory-motor information of concepts.

Sex and gender—biological and social constructs—significantly impact the prevalence of protective and risk factors, influencing the burden of Alzheimer's disease (AD; amyloid beta and tau) and other pathologies (e.g., cerebrovascular disease) which ultimately shape cognitive trajectories. Understanding the interplay of these factors is central to understanding resilience and resistance mechanisms explaining maintained cognitive function and reduced pathology accumulation in aging and AD. In this narrative review, the ADDRESS! Special Interest Group (Alzheimer's Association) adopted a multidisciplinary approach to provide the foundations and recommendations for future research into sex‐ and gender‐specific drivers of resilience, including a sex/gender‐oriented review of risk factors, genetics, AD and non‐AD pathologies, brain structure and function, and animal research. We urge the field to adopt a sex/gender‐aware approach to resilience to advance our understanding of the intricate interplay of biological and social determinants and consider sex/gender‐specific resilience throughout disease stages. Highlights: Sex differences in resilience to cognitive decline vary by age and cognitive status.Initial evidence supports sex‐specific distinctions in brain pathology.Findings suggest sex differences in the impact of pathology on cognition.There is a sex‐specific change in resilience in the transition to clinical stages.Gender and sex factors warrant study: modifiable, immune, inflammatory, and vascular. [ABSTRACT FROM AUTHOR]

Objectives: Sensory impairment is a hypothesized risk factor for cognitive decline; however, the psychosocial pathways are not well understood. We evaluated whether the association between visual impairment (VI) and cognitive decline was partially mediated via depressive symptoms, loneliness, or social activity. Methods: We used data from 2601 older adults enrolled in the Memory and Aging Project in 1997 and the Minority Aging Research Study in 2004 with neuropsychological tests across five domains measured annually for up to 16 years. VI was assessed with the Rosenbaum Pocket Vision Screener. Depressive symptoms, loneliness, and social activity were self‐reported using validated scales. We used structural equation models to estimate the associations of VI with baseline and change in cognitive function, directly and indirectly through each mediator (depressive symptoms, loneliness, and social activity). We evaluated mediation via "psychological distress" using a latent variable combining depressive symptoms and loneliness. Results: The association between VI and global cognitive decline was mediated via lower social activity (indirect effect) [95% confidence interval (CI)] of linear slope: −0.025 (−0.048, −0.011), via loneliness (−0.011 [95% CI: −0.028, −0.002]), and via psychological distress (−0.017 [95% CI: −0.042, −0.003]). We did not find sufficient evidence for mediation via depressive symptoms alone. Conclusions: The harmful effect of VI on cognitive decline may be partially mediated through loneliness and lower social activity. Key points: We evaluated whether psychosocial factors mediate the association between visual impairment and cognitive decline.With data from the Memory and Aging Project and the Minority Aging Research Study, we used structural equation models to estimate the total, direct, and indirect associations through each mediator (depressive symptoms, loneliness, lower social activity, and a latent variable, psychological distress, combining depressive symptoms and loneliness).We found evidence for partial mediation via social activity and loneliness. [ABSTRACT FROM AUTHOR]

INTRODUCTION: We compared gender disparities in later‐life memory, overall and by education, in India and the United States (US). METHODS: Data (N = 7443) were from harmonized cognitive assessment protocols (HCAPs) in the Longitudinal Aging Study of India‐Diagnostic Assessment of Dementia (LASI‐DAD; N = 4096; 2017‐19) and US Health and Retirement Study HCAP (HRS‐HCAP; N = 3347; 2016‐17). We derived harmonized memory factors from each study using confirmatory factor analysis. We used multivariable‐adjusted linear regression to compare gender disparities in memory function between countries, overall and by education. RESULTS: In the United States, older women had better memory than older men (0.28 SD‐unit difference; 95% CI: 0.22, 0.35). In India, older women had worse memory than older men (−0.15 SD‐unit difference; 95% CI: −0.20, −0.10), which attenuated with increasing education and literacy. CONCLUSION: We observed gender disparities in memory in India that were not present in the United States, and which dissipated with education and literacy. [ABSTRACT FROM AUTHOR]

Objectives: Semantic fluency is a prominent neuropsychological task, typically administered within the category 'animals'. With the increasing development of novel item-level metrics of semantic fluency, a concern around the validity of item-level analyses could be that personal background factors (e.g., hobbies like birdwatching or fishing) may disproportionally influence performance. We analyzed animal fluency performance at the item level and investigated the prevalence of individuals with abundant knowledge in specific classes of animals (e.g., birds, fish, insects) and the relationship of such knowledge with personal background factors and other cognitive tasks (episodic memory and executive functioning). Method: Participants included 736 Dutch middle-aged to older adults from the SMART-MR cohort (mean age 58 ± 9.4 years, 18% women). Individuals were asked to name as many animals as possible for 2 min. Number of people with abundant animal class knowledge was calculated for the ability to recall a series of minimum =5 and up to =15 animals within a specific class with at most one interruption by an animal from another class. Subsequent analyses to investigate relationships of abundant class knowledge with sociodemographic characteristics (t-tests and chi-square tests) and cognitive performance (linear regressions) were performed for a cut-off of =10 animals within a specific class (90th percentile), with a sensitivity analysis for =7 animals (67th percentile). Results: A total of 416 (56.2%) participants recalled a series of =5 animals from a specific class, 245 (33.3%) participants recalled =7, 78 (10.6%) participants recalled =10, and 8 (1.1%) participants recalled =15. Those who recalled a series of at least 10 animals within a class were older, more often men, and more often retired than those who did not. Moreover, they had a higher total score on animal fluency, letter fluency (i.e., executive functioning), and episodic memory tasks compared to those who did not. Discussion: Our results suggest that the benefit of abundant animal class knowledge gained by personal background does not disproportionally influence animal fluency performance as individuals with such knowledge also performed better on other cognitive tasks unrelated to abundant knowledge of animal classes. [ABSTRACT FROM AUTHOR]

Objective: To compare longitudinal verbal fluency performance among Latinx Spanish speakers who develop Alzheimer's disease to those who do not develop dementia in absolute number of words produced on each task and their ratio to combine both scores. Method: Participants included 833 Latinx Spanish-speaking older adults from a community-based prospective cohort in Manhattan. We performed growth curve modeling to investigate the trajectories of letter and semantic fluency, and their ratio (i.e., 'semantic index'), between individuals who developed Alzheimer's disease and those who did not (i.e., controls). The semantic index quantifies the proportion of words generated for semantic fluency in relation to the total verbal fluency performance. Results: Letter fluency performance did not decline in controls; we observed a linear decline in those who developed Alzheimer's disease. Semantic fluency declined in both groups and showed an increased rate of change over time in the incident Alzheimer's disease group; in comparison, the control group had a linear and slower decline. There were no group differences in the longitudinal trajectory (intercept and slope) of the semantic index. Conclusion: A decline in letter fluency and a more rapid and accelerating decline over time in semantic fluency distinguished people who developed Alzheimer's disease from controls. Using the semantic index was not a superior marker of incident Alzheimer's disease compared to examining the two fluency scores individually. Results suggest the differential decline in verbal fluency tasks, when evaluated appropriately, may be useful for early identification of Alzheimer's disease in Latinx Spanish speakers, a historically understudied population. [ABSTRACT FROM AUTHOR]

Purpose: In this study, we aim to understand whether and how performance in animal fluency (i.e., total correct word count) relates to linguistic levels and/or executive functions by looking at sequence information and item-level metrics (i.e., clusters, switches, and word properties). Method: Seven hundred thirty-one Dutch-speaking individuals without dementia from the Second Manifestations of ARTerial disease-Magnetic Resonance study responded to an animal fluency task (120 s). We obtained cluster size and number of switches for the task, and eight different word properties for each correct word produced. We detected variables that determine total word count with random forests, and used conditional inference trees to assess points along the scales of such variables, at which total word count changes significantly. Results: Number of switches, average cluster size, lexical decision response times, word frequency, and concreteness determined total correct word count in animal fluency. People who produced more correct words produced more switches and bigger clusters. People who produced fewer words produced fewer switches and more frequent words. Conclusions: Concurrent with existing literature, individuals without dementia rely on language and executive functioning to produce words in animal fluency. The novelty of our work is that such results were shown based on a data-driven approach using sequence information and item-level metrics. Supplemental Material: https://doi.org/10.23641/asha.23713269 [ABSTRACT FROM AUTHOR]

In normal aging, the cognitive domain of semantic memory remains preserved, while the domain of episodic memory declines to some extent. In Alzheimer's disease dementia, both semantic and episodic memory become impaired early in the disease process. Given the need to develop sensitive and accessible cognitive markers for early detection of dementia, we investigated among older adults without dementia whether item-level metrics of semantic fluency related to episodic memory decline above and beyond existing neuropsychological measures and total fluency score. Participants were drawn from the community-based Washington Heights–Inwood Columbia Aging Project cohort (N = 583 English speakers, Mage = 76.3 ± 6.8) followed up to five visits across up to 11 years. We examined the association of semantic fluency metrics with subsequent declines in memory performance using latent growth curve models covaried for age and recruitment wave. Results showed that item-level metrics (e.g., lexical frequency, age of acquisition, and semantic neighborhood density) were associated with a decline in episodic memory—even when covarying for other cognitive tests—while the standard total score was not. Moderation analyses showed that the relationship of semantic fluency metrics with memory decline did not differ across race, sex/gender, or education. In conclusion, item-level data hold a wealth of information with potential to reveal subtle semantic memory impairment, which tracks with episodic memory impairment, among older adults without dementia beyond existing neuropsychological measures. Implementation of psycholinguistic metrics may point to cognitive tools that have better prognostic value or are more sensitive to cognitive change in the context of clinical trials or observational studies. Public Significance Statement: This study found that alternative scores of semantic fluency (an existing cognitive test), based on each item instead of the total score, can provide additional information to reveal subtle cognitive impairment among older adults without dementia beyond existing cognitive measures. These findings are important because they show the value that item-level information may have in the search for sensitive and accessible cognitive markers for early detection of dementia. [ABSTRACT FROM AUTHOR]

INTRODUCTION: We used cultural neuropsychology‐informed procedures to derive and validate harmonized scores representing memory and language across population‐based studies in the United States and Mexico. METHODS: Data were from the Health and Retirement Study Harmonized Cognitive Assessment Protocol (HRS‐HCAP) and the Mexican Health and Aging Study (MHAS) Ancillary Study on Cognitive Aging (Mex‐Cog). We statistically co‐calibrated memory and language domains and performed differential item functioning (DIF) analysis using a cultural neuropsychological approach. We examined relationships among harmonized scores, age, and education. RESULTS: We included 3170 participants from the HRS‐HCAP (Mage = 76.6 [standard deviation (SD): 7.5], 60% female) and 2042 participants from the Mex‐Cog (Mage = 68.1 [SD: 9.0], 59% female). Five of seven memory items and one of twelve language items demonstrated DIF by study. Harmonized memory and language scores showed expected associations with age and education. DISCUSSION: A cultural neuropsychological approach to harmonization facilitates the generation of harmonized measures of memory and language function in cross‐national studies. HIGHLIGHTS: We harmonized memory and language scores across studies in the United States and Mexico.A cultural neuropsychological approach to data harmonization was used.Harmonized scores showed minimal measurement differences between cohorts.Future work can use these harmonized scores for cross‐national studies of Alzheimer's disease and related dementias. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Primary aims of this systematic review were to: (1) identify the range of subjective memory measures used in the stroke and stroke-related aphasia literature and (2) critically appraise their psychometric properties as well as (3) the methodological qualities of studies that included them, (4) investigate whether such measures provide an accurate reflection of memory impairments (i.e., in comparison to norms from age-matched, neurotypical participants), (5) document the representation of individuals with stroke-related aphasia, and (6) examine the extent to which subjective memory measures correlate with objective memory measures. Systematic review of the literature from 1970 to June 2019 using a comprehensive range of relevant search terms in EMBASE, Medline, PsychINFO, SCOPUS, and Web of Science. Eligibility criteria were for studies to include adults who had suffered of clinical stroke, to report a subjective memory measure that was completed by the stroke survivors, to be reported in a peer-reviewed journal, and to be published in English or Dutch. Quality appraisal was carried out for the included studies as well as the subjective memory measures they employed. A total of 7,077 titles or abstracts were screened, with 41 studies included in the quantitative and qualitative synthesis. Twenty-six subjective memory measures were used in the included studies. The critical appraisal of their psychometric properties and the methodological quality of the included studies revealed significant shortcomings; for example, neurotypical participants were included in only 14 of the 41 studies. When statistical comparisons were made, different outcomes arose. Only eight studies statistically compared subjective with objective memory measures. This literature domain currently provides an unclear picture as to how memory limitations affect participation in stroke and stroke-related aphasia. A broad range of subjective memory measures have been used to determine stroke survivors' perceptions of their everyday memory issues. Because of psychometric weaknesses such as inadequate reliability and cross-cultural validity among subjective memory measures, there remains a need to carefully review a given measure's properties to determine if it is appropriate for use with a given stroke survivor. Stroke survivors with aphasia have been infrequently included or inadequately described in studies of subjective memory measures, and thus how these individuals perceive their everyday memory abilities requires further investigation. Although the relationship between subjective and objective memory measures has been infrequently investigated by stroke researchers, both types of measures should be considered as they likely offer complementary rather than redundant information about stroke survivors' memory abilities. [ABSTRACT FROM AUTHOR]

Introduction: We examined whether educational attainment differentially contributes to cognitive reserve (CR) across race/ethnicity. Methods: A total of 1553 non‐Hispanic Whites (Whites), non‐Hispanic Blacks (Blacks), and Hispanics in the Washington Heights‐Inwood Columbia Aging Project (WHICAP) completed structural magnetic resonance imaging. Mixture growth curve modeling was used to examine whether the effect of brain integrity indicators (hippocampal volume, cortical thickness, and white matter hyperintensity [WMH] volumes) on memory and language trajectories was modified by education across racial/ethnic groups. Results: Higher educational attainment attenuated the negative impact of WMH burden on memory (β = −0.03; 99% CI: −0.071, −0.002) and language decline (β = −0.024; 99% CI:− 0.044, −0.004), as well as the impact of cortical thinning on level of language performance for Whites, but not for Blacks or Hispanics. Discussion: Educational attainment does not contribute to CR similarly across racial/ethnic groups. [ABSTRACT FROM AUTHOR]

Objective: Lack of social support is linked to lower cognitive function and cognitive decline. We investigated the effects of a specific type of social relationship, family ties, on cognitive trajectories in non-Hispanic whites, non-Hispanic blacks, and Hispanics. Methods: Using multiple-group latent growth curve models, we analyzed associations between the number of children/grandchildren/siblings/other relatives contacted within the past month at baseline and cognitive trajectories in 1420 older adults who were nondemented at baseline. Language, memory, and visuospatial abilities were assessed at baseline and at 18- and 24-month follow-ups for up to six visits. Inferential analyses assessed the differential effects of sex/gender and race/ ethnicity for each family tie. Results: Independent of all covariates, contact with more relatives was associated with better initial memory (b = .01) and language functioning (b = .01) across race/ethnicity and sex/gender. Conclusion: The size of peripheral rather than immediate family networks may be more likely to affect cognitive function in older adults. [ABSTRACT FROM AUTHOR]

Objectives: To better understand and compare effects of aging and education across domains of language and cognition, we investigated whether (a) these domains show different associations with age and education, (b) these domains show similar patterns of age-related change over time, and (c) education moderates the rate of decline in these domains. Method: We analyzed data from 306 older adults aged 55–85 at baseline of whom 116 returned for follow-up 4–8 years later. An exploratory factor analysis identified domains of language and cognition across a range of tasks. A confirmatory factor analysis analyzed cross-sectional associations of age and education with these domains. Subsequently, mixed linear models analyzed longitudinal change as a function of age and moderation by education. Results: We identified 2 language domains, that is, semantic control and semantic memory efficiency, and 2 cognitive domains, that is, working memory and cognitive speed. Older age negatively affected all domains except semantic memory efficiency, and higher education positively affected all domains except cognitive speed at baseline. In language domains, a steeper age-related decline was observed after age 73–74 compared to younger ages, while cognition declined linearly with age. Greater educational attainment did not protect the rate of decline over time in any domain. Discussion: Separate domains show varying effects of age and education at baseline, language versus cognitive domains show dissimilar patterns of age-related change over time, and education does not moderate the rate of decline in these domains. These findings broaden our understanding of age effects on cognitive and language abilities by placing observed age differences in context. [ABSTRACT FROM AUTHOR]

Semantic variant primary progressive aphasia (svPPA), a clinical syndrome characterized by loss of semantic knowledge, is associated with neurodegeneration that starts in the anterior temporal lobe (ATL) and gradually spreads towards posterior temporal and medial frontal areas. At the earliest stages, atrophy may be predominantly lateralized to either the left or right ATL, leading to different clinical profiles with the greatest impairment of word comprehension or visual/social semantics, respectively. We report the in-depth longitudinal investigation of cognitive and neuroanatomical features of JB, an unusual case of ATL neurodegeneration with relative sparing of left lateral ATL regions. Over the course of 9 years, neurodegeneration progressed to involve bilateral temporo-lateral and frontal regions, resulting in a relatively symmetric and diffuse frontotemporal atrophy pattern. In parallel, JB developed greater behavioral, cognitive, and language impairments, as well as signs of motor neuron disease at her last evaluation. Episodic memory and socio-emotional processing deficits arose, likely secondary to semantic verbal deficits, while visuospatial processing, executive function, and non-semantic language abilities remained largely unaffected throughout the course of the disease. The details of this rare case of early medial more than lateral ATL degeneration are consistent with a bilateral organization of the semantic system and, crucially, with a functional dissociation between medial paralimbic and lateral neocortical temporal regions. Cases of frontotemporal dementia (FTD) such as JB, who initially do not meet current clinical criteria for svPPA and instead present with some features of behavioral variant FTD, highlight the need for specific criteria for the right temporal variant of FTD that we propose could be called semantic variant FTD. [ABSTRACT FROM AUTHOR]

Objective: To determine the effect of three psycholinguistic variables—lexical frequency, age of acquisition (AoA), and neighborhood density (ND)—on lexical-semantic processing in individuals with non-fluent (nfvPPA), logopenic (lvPPA), and semantic primary progressive aphasia (svPPA). Identifying the scope and independence of these features can provide valuable information about the organization of words in our mind and brain. Method: We administered a lexical decision task—with words carefully selected to permit distinguishing lexical frequency, AoA, and orthographic ND effects—to 41 individuals with PPA (13 nfvPPA, 14 lvPPA, 14 svPPA) and 25 controls. Results: Of the psycholinguistic variables studied, lexical frequency had the largest influence on lexical-semantic processing, but AoA and ND also played an independent role. The results reflect a brain-language relationship with different proportional effects of frequency, AoA, and ND in the PPA variants, in a pattern that is consistent with the organization of the mental lexicon. Individuals with nfvPPA and lvPPA experienced an ND effect consistent with the role of inferior frontal and temporoparietal regions in lexical analysis and word form processing. By contrast, individuals with svPPA experienced an AoA effect consistent with the role of the anterior temporal lobe in semantic processing. Conclusions: The findings are in line with a hierarchical mental lexicon structure with a conceptual (semantic) and a lexeme (word-form) level, such that a selective deficit at one of these levels of the mental lexicon manifests differently in lexical-semantic processing performance, consistent with the affected language-specific brain region in each PPA variant. [ABSTRACT FROM AUTHOR]

Verbal fluency tasks are widely applied in a variety of languages, but whether the quality and quantity of responses are comparable across structurally different writing systems is debatable. For example, since there are no letters in a logographic, non-alphabetic language such as Chinese, the mechanisms speakers use to generate a list of words in a letter fluency task might be structurally different than those used by speakers of alphabetic languages. In this study, we investigated lexical retrieval strategies and approaches in letter and category fluency tasks among monolingual Mandarin speakers compared to monolingual English speakers. We found that the responses of Mandarin speakers are both qualitatively and quantitatively different in letter fluency, and qualitatively different in category fluency. These results suggest that differences in task completion among non-English-speaking populations are important to consider when using this extensively utilised cognitive and linguistic measure in research and clinic. [ABSTRACT FROM AUTHOR]

An review for the article "The white matter structural network underlying human tool use and tool understanding" by A. Caramazza and others published within the issue is presented.