Assessment of functional change and cognitive correlates in the progression from healthy cognitive aging to dementia

Functional neuroplasticity of facilitation and interference effects on inhibitory control following 3-month physical exercise in aging

Preservation of executive function, like inhibition, closely links to the quality of life in senior adults. Although neuroimaging literature has shown enhanced inhibitory function followed by aerobic exercise, current evidence implies inconsistent neuroplasticity patterns along different time durations of exercise. Hence, we conducted a 12-week exercise intervention on 12 young and 14 senior volunteers and repeatedly measured the inhibitory functionality of distinct aspects (facilitation and interference effects) using the numerical Stroop task and functional Magnetic Resonance Imaging. Results showcased improved accuracy and reduced reaction times (RT) after 12-week exercise, attributed to frontoparietal and default mode network effects. In young adults, the first phase (0 to six weeks) exercise increased the activation of the right superior medial frontal gyrus, associated with reduced RT in interference, but in the second intervention phase (six to twelve weeks), the decreased activation of the left superior medial frontal gyrus positively correlated with reduced RT in facilitation. In senior adults, the first six-week intervention led to reduced activations of the inferior frontal gyrus, inferior parietal gyrus, and default mode network regions, associated with the reduced RT in interference. Still, in the second intervention phase, only the visual area exhibited increased activity, associated with reduced RT in interference. Except for the distinctive brain plasticity between the two phases of exercise intervention, the between-group comparison also presented that the old group gained more cognitive benefits within the first six weeks of exercise intervention; however, the cognitive improvements in the young group occurred after six weeks of intervention. Limited by the sample size, these preliminary findings corroborated the benefits of aerobic exercise on the inhibitory functions, implying an age × exercise interaction on the brain plasticity for both facilitation and interference.

Assessing the impact of age on everyday cognitive function with a virtual environment task: The EcoKitchen

More realistic assessment tools are imperative for a better understanding of the impact of age-related cognitive deficits on functional status. With this in mind, we probed the ability of the EcoKitchen, a non-immersive virtual environment task with increasing executively demanding kitchen chores, to detect the effects of aging on the simulated everyday functioning of healthy adults. Fifty-three adults (age between 23 and 77 years) were assessed with the EcoKitchen and a set of conventional paper-and-pencil neuropsychological tests. The associations between the baseline features of study participants and each of the two different assessment methods were examined. The associations between the EcoKitchen variables and an executive composite score were also explored. Our results showed that older individuals present deficits in the performance of both the EcoKitchen task and standard assessment methods. Notably, we found that, unlike conventional tests, accuracy in the EcoKitchen task was not related to the education level and IQ score of participants. Moreover, the EcoKitchen performance time was significantly correlated with executive tests. We have demonstrated that the EcoKitchen task, an ecologically relevant computerized neuropsychological assessment tool, might be more suitable than classic paper-and-pencil tests to capture the impact of aging on everyday cognitive function, as it proved to be less prone to the influence of confounding factors. Additionally, we have shown that executive function plays an important role in the timely performance of cognitively challenging virtual environment tasks.

Theory of Mind and Executive Functions in Individuals with Mild Cognitive Impairment or Healthy Aging

Social cognition involves skills for maintaining harmonious personal and social relationships throughout life. Social cognition issues, including Theory of Mind (ToM), can significantly impact the well-being of older individuals and intensify with the onset of neurological conditions. Mild Cognitive Impairment (MCI) is a state between healthy and pathological neurocognitive aging, where monitoring social functions is crucial. Despite numerous studies on ToM challenges in older adults and cognitive disorders, the underlying mechanisms remain debated. Uncertainty exists regarding whether ToM deficits are related to other cognitive functions, such as Executive Functions (EFs). Our study examined the correlation between EF and ToM performance in 32 MCI patients and 36 healthy elderly controls. The findings revealed a link between EF and ToM performance among healthy elderly individuals. Specifically, within the assessed EFs, the role of the working memory (WM) emerged. The study also highlighted distinctions between the MCI group and the healthy elderly group, showing that despite a general reduction in cognitive performance, the condition could impact these abilities in different ways. The study contributes to the literature, fostering comprehension of the mechanisms underlying ToM difficulties, while also paving the way for targeted interventions and enhanced clinical or preventative care.

Assessing functional ability of healthy adults with the Night Out Task

Objective: Given the negative health outcomes associated with functional loss, there is need to better understand the trajectory of functional change and compensation use with age. Many older adults successfully age in place, and there is not a one-to-one relationship between cognitive changes and ability to live independently. This study compared healthy age cohorts' performance and approach on a functional measure, particularly examining compensatory strategy use to support task performance. Methods: 57 young adults (YAs; ages 18-39), 42 young-old adults (YOAs; ages 60-69) and 47 old-old (OOAs; ages 70+) completed the Night Out Task (NOT); an open-ended functional assessment in which participants complete eight subtasks in preparation for a night out with a friend (e.g. prepare tea and gather items for a recipe). The NOT measures both primary outcome variables (e.g. time and accuracy), error types and 'compensation variables', which are process-approach variables intended to map on to the types of compensatory strategies individuals use in their everyday lives (e.g. planning and checking). Results: Results revealed that YAs performed better than the oldest group on the NOT in accuracy, execution time and number of both inefficient and inaccurate/incomplete errors. YAs additionally used fewer compensatory strategies than both older groups. Only one compensation variable had a positive relationship to outcome; double-checking was related to improved accuracy and fewer inaccurate/incomplete errors within the oldest cohort. Conclusion: Together these findings support a spectrum of functional change with age. While compensation use increased with age, the relationship between compensation use and outcome was unclear. Future work is needed to understand under what conditions older adults' self-initiate compensation use and to understand the relationship between compensation use and outcome.

Longitudinal changes on the Independent Living Scale in amnestic mild cognitive impairment

The Independent Living Scales (ILS) is an objective measure of day-to-day functioning, which can be used to aid in diagnosing dementia in older adults with cognitive impairments. However, no studies have examined this measure longitudinally in individuals with mild cognitive impairment (MCI), a prodromal phase of dementia. Three subscales of the ILS (Managing Money, Managing Home and Transportation, Health and Safety) were administered to a sample of 94 individuals with amnestic MCI twice across 15 months. A measure of global cognition (Total Scale score on the Repeatable Battery for the Assessment of Neuropsychological Status [RBANS]) was also administered twice. In this MCI sample, two of the three subscales of the ILS showed a significant decline over time, where the third ILS subscale and the Total Scale score of the RBANS did not change. Regression-based change models showed that baseline ILS scores were most strongly predictive of follow-up ILS scores compared to RBANS scores at baseline and follow-up and demographic variables (age, education, and sex). These results provide additional information on the longitudinal change on the ILS in a sizeable cohort of older individuals with amnestic MCI, which may make this scale more useful in identifying progression to dementia.

Capturing Cognitive Aging in Vivo: Application of a Neuropsychological Framework for Emerging Digital Tools

As the global burden of dementia continues to plague our healthcare systems, efficient, objective, and sensitive tools to detect neurodegenerative disease and capture meaningful changes in everyday cognition are increasingly needed. Emerging digital tools present a promising option to address many drawbacks of current approaches, with contexts of use that include early detection, risk stratification, prognosis, and outcome measurement. However, conceptual models to guide hypotheses and interpretation of results from digital tools are lacking and are needed to sort and organize the large amount of continuous data from a variety of sensors. In this viewpoint, we propose a neuropsychological framework for use alongside a key emerging approach-digital phenotyping. The Variability in Everyday Behavior (VIBE) model is rooted in established trends from the neuropsychology, neurology, rehabilitation psychology, cognitive neuroscience, and computer science literature and links patterns of intraindividual variability, cognitive abilities, and everyday functioning across clinical stages from healthy to dementia. Based on the VIBE model, we present testable hypotheses to guide the design and interpretation of digital phenotyping studies that capture everyday cognition in vivo. We conclude with methodological considerations and future directions regarding the application of the digital phenotyping approach to improve the efficiency, accessibility, accuracy, and ecological validity of cognitive assessment in older adults.

A Comparison of Functional Abilities in Individuals with Mild Cognitive Impairment and Parkinson's Disease with Mild Cognitive Impairment Using Multiple Assessment Methods

OBJECTIVE

This study used multiple assessment methods to examine instrumental activities of daily living (IADLs) performance in individuals with Parkinson's disease with mild cognitive impairment (PD-MCI) compared to individuals with mild cognitive impairment (MCI) and cognitively healthy older adults (HOA). Associations between functional performance and cognition were also examined.

METHODS

Eighteen individuals with PD-MCI, 48 individuals with MCI, and 66 HOAs were assessed with multiple IADL measures, including direct observation, a performance-based measure, and self- and informant-report questionnaires. Performance on the direct-observation measure was further characterized by coding for four error types: omissions, substitutions, and inefficient and irrelevant/off-task actions.

RESULTS

Both the PD-MCI and MCI groups performed more poorly on the overall score for all IADL measures relative to HOAs. Although the PD-MCI and MCI groups did not differ in overall performance, on the direct-observation measure, the PD-MCI group took longer and made more inefficient and irrelevant/off-task errors relative to the HOA and MCI groups, whereas the MCI group made more omission and substitution errors relative to HOAs. Further, the pattern of cognitive correlates that associated most strongly with the functional measures varied across groups and functional assessment methods.

CONCLUSION

Compared to HOAs, PD-MCI and MCI groups demonstrated increased difficulties performing everyday activities, and cognitive and motor abilities differentially contributed to the everyday task difficulties of these two groups.

Predictors of functional impairment and awareness in people with dementia, mild cognitive impairment and healthy older adults from a middle-income country

Objective

To investigate the demographic, clinical and cognitive correlates of functional capacity and its awareness in people with dementia (PwD; n = 104), mild cognitive impairment (PwMCI; n = 45) and controls (healthy older adults; n = 94) in a sample from a middle-income country.

Methods

Dementia and MCI were diagnosed, respectively, with DSM-IV and Petersen criteria. Performance in activities of daily living (ADL) at three different levels [basic (The Katz Index of Independence), instrumental (Lawton instrumental ADL scale) and advanced (Reuben's advanced ADL scale)], measured through self- and informant-report, as well as awareness (discrepancy between self- and informant-report), were compared between groups. Stepwise regression models explored predictors of ADL and their awareness.

Results

PwD showed impairment in all ADL levels, particularly when measured through informant-report. No differences were seen between controls and PwMCI regardless of measurement type. PwD differed in awareness of instrumental and basic, but not of advanced ADL, compared to controls. Age, gender, education and fluency were the most consistent predictors for ADL. Diagnosis was a significant predictor only for instrumental ADL. Awareness of basic ADL was predicted by memory, and awareness of instrumental ADL was predicted by general cognitive status, educational level, and diagnosis.

Conclusion

Results reinforce the presence of lack of awareness of ADL in PwD. Use of informant-reports and cognitive testing for fluency are suggested for the clinical assessment of ADL performance. Finally, assessment of instrumental ADL may be crucial for diagnostic purposes.

Subjective executive dysfunction in patients with primary brain tumors and their informants: relationships with neurocognitive, psychological, and daily functioning

OBJECTIVE

We assessed agreement between patient- and informant-report on the Behavior Rating Inventory of Executive Function - Adult (BRIEF-A) in patients with primary brain tumors (PBT) and differences on BRIEF-A in neurocognitive (intact v. impaired), psychological (asymptomatic v. distressed), and functional (independent v. dependent) categories using both patient- and informant-report.

METHOD

PBT patients (n = 102) completed neuropsychological evaluations including the BRIEF-A, clinical interview, neurocognitive tests, and mood questionnaires. Correlations between the BRIEF-A and Informant (n = 39) were conducted. Differences in patient and informant BRIEF-A indices were investigated across five classifications: neurocognitive functioning, psychological functioning, medication management, appointment management, and finance management.

RESULTS

Patient and informant BRIEF were correlated. There was no difference on BRIEF-A or Informant indices for intact v. impaired neurocognitive status. Higher BRIEF-A and Informant indices were observed among psychologically distressed v. asymptomatic patients. Results showed higher BRIEF indices among those requiring assistance with medication, appointments, and finances.

CONCLUSIONS

Patients and informants agreed in their reports of executive function (EF). These reports, while not different in neurocognitive classification, were different in psychological functioning and in those needing assistance with instrumental activities of daily living (IADL). Patient- and informant-reported EF may provide important data regarding psychological and IADL functioning in this population.

The Usefulness of Evaluating Performance of Activities in Daily Living in the Diagnosis of Mild Cognitive Disorders

The Assessment of Activities of Daily Living (ADL) is paramount to ensure the accurate early diagnosis of neurocognitive disorders. Unfortunately, the most common ADL tools are limited in their use in a diagnostic process. Hence, we set out to validate a tool to evaluate basic (b-), instrumental (i-), and advanced (a-) ADL called the Brussels Integrated Activities of Daily Living Inventory (BIA). At the geriatric day hospital of the University Hospital Brussels (Belgium) older persons (65+) labelled as Cognitively Healthy Persons (CHP) (n = 47), having a Mild Cognitive Impairment (MCI) (n = 39), and having Alzheimer's disease (AD) (n = 44) underwent a diagnostic procedure for neurocognitive disorders. Additionally, the BIA was carried out. An exploration using both (cumulative) logistic regressions and conditional inference trees aimed to select the most informative scales to discriminate between the HCP, persons with MCI and AD. The distinction between CHP and MCI and between MCI and AD was moderately successful with the i-ADLs, in addition to age. Therefore, it is advisable to conduct a multidomain assessment in which the i-ADL could serve as non-invasive and non-time-consuming screening, while the BIA might be useful for diagnostics and disease management.

Implementing advance care planning in early dementia care: results and insights from a pilot interventional trial

BACKGROUND

Advance care planning (ACP) is particularly appropriate for persons with early dementia (PWED) since it promotes conversations about dementia-specific illness scenarios, addresses inconsistencies between advance directives and patients' observed behavior, emphasizes prospective and relational autonomy, and may be generally consistent with older persons' decision-making needs. However, despite evidence of its benefits, ACP is yet to become widely used among PWED. In this paper, we present a dementia-specific tool developed in Western Switzerland, discuss results of a pilot trial designed to promote ACP among PWED and their relatives, and discuss the feasibility and acceptability of the intervention and the study protocol in prevision of a large scale trial.

METHODS

This one-arm pre-post pilot trial consisted of four visits, with visits 2 and 3 being the ACP intervention. Quantitative outcome measures during visit 1 and 4 assessed the aptitude of the intervention to support PWED autonomy and relatives' knowledge of PWED's preferences. Feasibility was explored according to how the recruitment procedure unfurled and based on the necessary revisions to the study protocol and healthcare providers' reason for excluding a PWED from the study. Acceptability was assessed according to pre-post evaluations, difficulties regarding the intervention or trial participation, and pre-post qualitative interviews regarding participants' reasons to participate to the study, satisfaction with the tool and difficulties perceived.

RESULTS

The ACP intervention itself was well received by PWED and their relatives that expressed satisfaction with the procedure, especially regarding the opportunity to discuss a sensitive topic with the help of a facilitator. Five main challenges in terms of feasibility were 1) to locate eligible patients, 2) to tailor recruitment procedures to recruitment locations, 3) to adapt inclusion criteria to clinical routines, 4) to engage PWED and their relatives in ACP, and 5) to design a trial that does not burden PWED. Despite these challenges, the intervention increased the number of advance directives, the concordance between PWED's preferences and relatives' decision on their behalf, and relatives' perceived control over healthcare decisions.

CONCLUSION

Misconceptions about dementia and ACP, in the patient, relatives, and healthcare providers, combined with structural and institutional challenges, have the power to impede research and implementation of ACP in dementia care. For this reason, we conclude that a large scale trial to test a dementia-specific tool of ACP is currently not feasible in Western Switzerland and should be endorsed in a systemic approach of ACP.

TRIAL REGISTRATION

This trial was registered in the database clinicaltrial.gov with the number NCT03615027 .

Subtle Changes in Medication-taking Are Associated With Incident Mild Cognitive Impairment

INTRODUCTION

Medication-taking is a routine instrumental activity of daily living affected by mild cognitive impairment (MCI) but difficult to measure with clinical tools. This prospective longitudinal study examined in-home medication-taking and transition from normative aging to MCI.

METHODS

Daily, weekly, and monthly medication-taking metrics derived from an instrumented pillbox were examined in 64 healthy cognitively intact older adults (Mage=85.5 y) followed for a mean of 2.3 years; 9 transitioned to MCI during study follow-up.

RESULTS

In the time up to and after MCI diagnosis, incident MCI participants opened their pillbox later in the day (by 19 min/mo; β=0.46, P<0.001) and had increased day-to-day variability in the first pillbox opening over time (by 4 min/mo) as compared with stable cognitively intact participants (β=4.0, P=0.003).

DISCUSSION

Individuals who transitioned to MCI opened their pillboxes later in the day and were more variable in their medication-taking habits. These differences increased in the time up to and after diagnosis of MCI. Unobtrusive medication-taking monitoring is an ecologically valid approach for identifying early activity of daily living changes that signal transition to MCI.

The night out task and scoring application: an ill-structured, open-ended clinic-based test representing cognitive capacities used in everyday situations

OBJECTIVE

The night out task (NOT) was developed as a naturalistic, open-ended, multitasking measure that requires individuals to complete eight subtasks comparable to those encountered during real-world functioning (e.g., pack travel bag, prepare tea). We examined psychometric properties and administration feasibility of this direct observation measure within a clinic-like setting using a tablet-based coding application.

METHOD

A sample of 148 community-dwelling older adults (82% cognitively healthy; 18% mild cognitive impairment) and 57 younger adults completed the NOT along with other neurocognitive tests and questionnaires.

RESULTS

Inter-rater reliability across NOT primary (i.e., time, accuracy, efficiency) and process-related (e.g., error-types, self-corrections) variables was mostly excellent. NOT primary measures showed expected patterns of convergent and discriminant validity with measures of cognition, demographics, and well-being. External validity was established by the NOT ability to distinguish between age and diagnostic (cognitively healthy vs. mild cognitive impairment) groups. Demonstrating incremental validity, the NOT primary variables (execution time in particular) were predictive of self-reported functional abilities and completion quality of in-home everyday tasks over and earlier variables such as demographics, cognition, and mobility.

CONCLUSIONS

These findings suggest that the NOT and its app interface, which allows for continuous logging of observations, are a feasible in-clinic measure to assess cognitive capacities important for real-world functioning. With further validation, the NOT may allow for earlier detection of functional difficulties. Understanding errors and strategies used during NOT performance could also have implications for individualized interventions.

The goal-control model: An integrated neuropsychological framework to explain impaired performance of everyday activities

OBJECTIVE

This review describes the relatively small body of neuropsychological and cognitive research conducted over the past 100 years focused on theoretical models explaining the neurocognitive processes that support everyday functioning and the breakdown of functional abilities in the face of neurological damage or disease.

METHOD

The historical roots of the theories of everyday activities based on direct observation of behavior in neurology and diary reports of everyday errors in cognitive psychology are presented, followed by a review of the empirical findings and resulting theoretical conceptualizations from case studies and group studies of various clinical populations in neuropsychology.

RESULTS

We conclude with a new framework (the goal-control model) that integrates the most recent empirical findings in neuropsychology with mechanisms proposed by cognitive models.

CONCLUSIONS

The goal-control model offers empirically supported solutions to understanding and predicting functioning in the real world. This new model generates testable predictions for future research and provides guidance for clinical assessment and interventions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Mild cognitive impairment history and current procedures in low- and middle-income countries: a brief review

Mild cognitive impairment (MCI) is a widely studied concept that has changed over time. Epidemiology, diagnosis, costs, prognostics, screening procedures, and categorization have been extensively discussed. However, unified guidelines are still not available, especially considering differences between low- and middle-income countries (LMIC) and high-income countries (HIC).

Age Differences in the Subcomponents of Executive Functioning

OBJECTIVES

Across the life span, deficits in executive functioning (EF) are associated with poor behavioral control and failure to achieve goals. Though EF is often discussed as one broad construct, a prominent model of EF suggests that it is composed of three subdomains: inhibition, set shifting, and updating. These subdomains are seen in both younger (YA) and older adults (OA), with performance deficits across subdomains in OA. Therefore, our goal was to investigate whether subdomains of EF might be differentially affected by age, and how these differences may relate to broader global age differences in EF.

METHODS

To assess these age differences, we conducted a meta-analysis at multiple levels, including task level, subdomain level, and of global EF. Based on previous work, we hypothesized that there would be overall differences in EF in OA.

RESULTS

Using 1,268 effect sizes from 401 articles, we found overall differences in EF with age. Results suggested that differences in performance are not uniform, such that variability in age effects emerged at the task level, and updating was not as affected by age as other subdomains.

DISCUSSION

These findings advance our understanding of age differences in EF, and stand to inform early detection of EF decline.

Web-Based Cognitive Testing of Older Adults in Person Versus at Home: Within-Subjects Comparison Study

Background

Web-based research allows cognitive psychologists to collect high-quality data from a diverse pool of participants with fewer resources. However, web-based testing presents unique challenges for researchers and clinicians working with aging populations. Older adults may be less familiar with computer usage than their younger peers, leading to differences in performance when completing web-based tasks in their home versus in the laboratory under the supervision of an experimenter.

Objective

This study aimed to use a within-subjects design to compare the performance of healthy older adults on computerized cognitive tasks completed at home and in the laboratory. Familiarity and attitudes surrounding computer use were also examined.

Methods

In total, 32 community-dwelling healthy adults aged above 65 years completed computerized versions of the word-color Stroop task, paired associates learning, and verbal and matrix reasoning in 2 testing environments: at home (unsupervised) and in the laboratory (supervised). The paper-and-pencil neuropsychological versions of these tasks were also administered, along with questionnaires examining computer attitudes and familiarity. The order of testing environments was counterbalanced across participants.

Results

Analyses of variance conducted on scores from the computerized cognitive tasks revealed no significant effect of the testing environment and no correlation with computer familiarity or attitudes. These null effects were confirmed with follow-up Bayesian analyses. Moreover, performance on the computerized tasks correlated positively with performance on their paper-and-pencil equivalents.

Conclusions

Our findings show comparable performance on computerized cognitive tasks in at-home and laboratory testing environments. These findings have implications for researchers and clinicians wishing to harness web-based testing to collect meaningful data from older adult populations.

The Clinical Utility and Ecological Validity of the Medication Management Ability Assessment in Older Adults with and without Dementia

OBJECTIVE

Older adults are susceptible to medication nonadherence, which may signify functional decline. Thus, performance-based proxies of medication-taking behavior may help diagnose dementia. We assessed the Medication Management Ability Assessment's (MMAA) clinical utility and ecological validity.

METHOD

This was a retrospective chart review of 180 outpatients (age = 72 ± 8 years) who completed the MMAA during clinical evaluations. Forty-seven were cognitively normal (CN), 103 had mild cognitive impairment (MCI), and 30 had dementia. Most (136) were independent in medication management, whereas 28 were assisted and 16 were dependent. Kruskal-Wallis tests assessed whether MMAA scores differed by diagnosis and independence. Receiver operating characteristic (ROC) analyses identified diagnostic cut-offs. Classification accuracy estimates were derived.

RESULTS

MMAA performance differed across diagnosis as expected (p's < .001). Those who were independent in medication management outperformed assisted and dependent counterparts (p's < .001). Assisted and dependent cases were no different. At a cut-off = 23, the MMAA was good-to-strong in distinguishing dementia from CN cases (Sn = 0.96, Sp = 0.83), dementia from MCI (Sn = 0.70, Sp = 0.83), and dementia from functionally unimpaired cases (Sn = 0.78, Sp = 0.83). At a cut-off = 27, it had good sensitivity but weaker specificity when distinguishing both MCI and all cognitively impaired patients (MCI and dementia) from CN cases (Sn = 0.81, Sp = 0.66 and Sn = 0.81, Sp = 0.72, respectively).

CONCLUSIONS

The MMAA has ecological validity and clinical utility in identifying dementia. Its inclusion in neuropsychological practice may be especially useful when medication mismanagement is suspected.

Insight into memory and functional abilities in individuals with amnestic mild cognitive impairment

OBJECTIVE

Accurate insight into one's abilities facilitates engagement in rehabilitation and implementation of compensatory strategies. In this study, self-awareness, self-monitoring, and a new self-updating construct of insight were examined in amnestic mild cognitive impairment (aMCI).

METHOD

Individuals with aMCI and healthy older adults (HOAs) completed a list-learning task in a laboratory setting, and a naturalistic task of everyday functioning in a campus apartment along with other standardized neuropsychological tests. Participants made predictions about performance on the memory and functional tasks prior to task experience (self-awareness), immediately after task experience (self-monitoring), and after a delay (self-updating).

RESULTS

Individuals with aMCI performed more poorly than HOAs on the memory task and other neuropsychological tests but not the functional task. For both the memory and functional task, performance predictions and prediction accuracy measures revealed that the aMCI group exhibited intact self-awareness, self-monitoring, and self-updating. Prediction accuracy measures showed some association with an executive composite but not a memory composite.

DISCUSSION

Participants with aMCI demonstrated intact self-awareness, self-monitoring, and self-updating for a memory and functional task despite exhibiting poorer performance on neurocognitive tests compared to HOAs. These findings suggest that, even as memory in aMCI degrades, executive abilities may help sustain insight into difficulties, enabling adoption of cognitive strategies to support difficulties.

Regional Hypoperfusion Predicts Decline in Everyday Functioning at Three-Year Follow-Up in Older Adults without Dementia

BACKGROUND

Increasing evidence indicates that cerebrovascular dysfunction may precede cognitive decline in aging and Alzheimer's disease (AD). Reduced cerebral blood flow (CBF) is associated with cognitive impairment in older adults. However, less is known regarding the association between CBF and functional decline, and whether CBF predicts functional decline beyond cerebrovascular and metabolic risk factors.

OBJECTIVE

To examine the association between regional CBF and functional decline in nondemented older adults.

METHOD

One hundred sixty-six (N = 166) participants without dementia from the Alzheimer's Disease Neuroimaging Initiative underwent neuropsychological testing and neuroimaging. Pulsed arterial spin labeling magnetic resonance imaging was acquired to quantify resting CBF. Everyday functioning was measured using the Functional Assessment Questionnaire at baseline and annual follow-up visit across three years.

RESULTS

Adjusting for age, education, sex, cognitive status, depression, white matter hyperintensity volume, cerebral metabolism, and reference (precentral) CBF, linear mixed effects models showed that lower resting CBF at baseline in the medial temporal, inferior temporal, and inferior parietal lobe was significantly associated with accelerated decline in everyday functioning. Results were similar after adjusting for conventional AD biomarkers, including cerebrospinal fluid (CSF) amyloid-β (Aβ) and hyperphosphorylated tau (p-tau) and apolipoprotein E (APOE) ɛ4 positivity. Individuals who later converted to dementia had lower resting CBF in the inferior temporal and parietal regions compared to those who did not.

CONCLUSION

Lower resting CBF in AD vulnerable regions including medial temporal, inferior temporal, and inferior parietal lobes predicted faster rates of decline in everyday functioning. CBF has utility as a biomarker in predicting functional declines in everyday life and conversion to dementia.

Influence of age and education on a performance-based measure of everyday functioning

Sociodemographic variables, such as age and education, influence the determination of impairment on neuropsychological tests, but their influence on impairment determinations for tests of everyday functioning is less well defined. Existing studies suggest that older age and lower education levels are associated with worse everyday functioning when assessed by self- or collateral-report. This relationship, however, has not been thoroughly investigated with performance-based methods of everyday functioning. This study aimed to determine the influence of sociodemographic factors on the Functional Impact Assessment (FIA), a performance-based measure of everyday functioning that includes measures of both accuracy and speed. Seventy-three healthy individuals, ages 42 - 88 years, completed the FIA and an additional everyday functioning self-report questionnaire (Functional Activities Questionnaire). Using a multiple regression statistical approach, age and education predicted overall FIA accuracy, while age alone predicted FIA speed. Sociodemographic variables continued to predict FIA performance when controlling for overall cognitive functioning. Sociodemographic variables were unrelated to FAQ scores. These findings indicate that age and education are associated with scores on a performance-based test of everyday functioning. Demographic corrections may improve accuracy in determining functional impairment, but more research is needed given the complex relationships among demographic factors, healthy aging, and dementia risk.

The Everyday Compensation (EComp) Questionnaire: Construct Validity and Associations with Diagnosis and Longitudinal Change in Cognition and Everyday Function in Older Adults

OBJECTIVE

The Everyday Compensation scale (EComp) is an informant-rated questionnaire designed to measure cognitively based compensatory strategies that support both everyday memory and executive function in the context of completing instrumental activities of daily living (IADLs). Although previous findings provided early support for the usefulness of the initial version of EComp, the current paper further describes the development, refinement, and validation of EComp as a new assessment tool of compensation for IADLs.

METHOD

Confirmatory factor analysis (CFA) was used to examine its factor structure. Convergent and predictive validity was evaluated by examining the relationship between EComp and markers of disease, including diagnosis, cognitive change, and trajectories of functional abilities.

RESULTS

CFA supported a general compensation factor after accounting for variance attributable to IADL domain-specific engagement. The clinical groups differed in compensatory strategy use, with those with dementia using significantly fewer compensatory strategies as compared to individuals with normal cognition or mild cognitive impairment. Greater levels of compensation were related to better cognitive functions (memory and executive function) and functional abilities, as well as slower rates of cognitive and functional decline over time. Importantly, higher levels of compensation were associated with less functional difficulties and subsequently slower rate of functional decline independent of the level of cognitive impairment.

CONCLUSIONS

Engagement in compensatory strategies among older adults has important implications for prolonging functional independence, even in those with declining cognitive functioning. Results suggest that the revised EComp is likely to be useful in measuring cognitively based compensation in older adults.

The Construction and Evaluation of Executive Attention Training to Improve Selective Attention, Focused Attention, and Divided Attention for Older Adults With Mild Cognitive Impairment: A Randomized Controlled Trial

OBJECTIVES

To examine the immediate and long-term effects of executive attention training on selective attention, focused attention, and divided attention in older adults with mild cognitive impairment.

METHODS

A double-blind, multisite randomized controlled trial at five sites. Seventy participants (mean age: 78.19 ± 7.22 years) were assigned to an experimental group (executive attention training, n = 35) or an active control group (n = 35). The training duration was the same for both groups (45 minutes per session, 3 times per week, 18 sessions in total). Primary outcome measure was selective attention (Digit Span Task). Secondary outcome measures included focused attention (Stroop Color Word Test) and divided attention (Trail-Making Test Part B). Data were collected at pretest, post-test, 3-month follow-up, and 6-month follow-up.

RESULTS

In GEE analysis, findings indicated a significant improvement in selective attention at post-test, whereas divided attention showed significant reducing omission error at 3-month follow-up. There was no significant effect of group in focused attention associated with the executive attention training compared with active control group.

CONCLUSION

The executive attention training significantly improved selective attention and divided attention performance. Future studies should identify transfer effects of attention training, and that can employ early screening to provide integrated attention training, and decrease its relevant risks on competency in performing daily activities, such as falling and driving.

Prospective memory partially mediates the association between aging and everyday functioning

Objective: Older adults commonly experience declines in everyday functioning, the reasons for which are multifactorial. Prospective memory (PM), or remembering to carry out intended actions, can be an executively demanding cognitive process that declines with older age and is independently associated with a variety of everyday functions (e.g. taking medication). This study examined the hypothesis that PM mediates the relationship between older age and poorer everyday functioning.Method: A total of 468 community-dwelling adults (ages 18-75) with a range of medical comorbidities (e.g. viral infection) were classified as dependent on four well-validated measures of manifest everyday functioning: activities of daily living, employment status, the Karnofsky Scale of Performance Status, and self-reported cognitive symptoms. Participants completed the Memory for Intentions Test (MIsT) to measure PM, alongside clinical tests of executive functions and retrospective memory.Results: Controlling for education and comorbidities, bootstrap analysis revealed a significant direct effect of age on everyday functioning and a significant mediated effect of age on everyday functioning through the indirect effect of time-based b = .006 [.003, .010] and event-based PM (b = .005, [.002, .009]), as well as slightly smaller effects for executive functions (b = .003, [.001, .005]) and retrospective memory (b = .002, [.001, .005]).Conclusions: These cross-sectional data suggest that executively demanding aspects of declarative memory play an important partial mediating role between an individual factor (i.e. age) and daily life activities, and highlight the possible benefit of targeting PM for improving everyday functioning in older adults.

The relationship between basic, instrumental, and advanced activities of daily living and executive functioning in geriatric patients with neurocognitive disorders

OBJECTIVE

Although many studies explored the relationship between executive functions (EF) and activities of daily living (ADLs) in cognitive disorders, previous studies used measurements without well-defined levels of ADLs. This study explored the relationship between EF and the threefold classification of everyday functioning (basic or b-, instrumental or i-, and advanced or a-ADLs) and examined how EF account for the variance in this triad of everyday functioning.

METHODS

A sample of 44 cognitively healthy persons, 41 persons with mild cognitive impairment, and 35 persons with Alzheimer disease were assessed with comprehensive measures of EF and the b-, i-, and a-ADL tools.

RESULTS

Correlations demonstrated that subjects with higher executive dysfunctions have more limitations in b-, i-, and a-ADLs. The highest significant correlations with measures of EF were seen in i- and a-ADLs (ranging from r = -0.193 to r = -0.559, P < 0.05). However, correlations with a-ADLs were not stronger than with i-ADLs. The multivariate analyses revealed Trail Making Test A (TMT-A) as a significant contributor of everyday functioning in b-ADLs, as well as i- and a-ADLs, and Clock Drawing Test (CDT) and Animal Fluency Test (AFT) seemed to contribute significantly to variance in i- and a-ADLs.

CONCLUSIONS

EF are less related to b-ADLs than i- and a-ADLs and contribute to the same amount of variance to limitations in both i- and a-ADLs. This study recommends using the TMT-A, CDT, and AFT as screening tools to indicate the need for profound evaluation of ADLs in older persons with neurocognitive disorders.

Windows to functional decline: Naturalistic eye movements in older and younger adults

Subtle changes in everyday tasks precede and predict future disability in older adults. Eye tracking may provide a sensitive tool for detecting subtle disruption of everyday task performance and informing the mechanism(s) of breakdown. We tracked eye movements of healthy older adults (OA, n = 24) and younger adults (YA, n = 25) while they passively viewed a naturalistic scene (Passive Viewing condition) and then verbally reported the necessary steps for achieving a task goal (e.g., pack a lunch; Verbalize Goal condition). Participants also completed a performance-based task of packing a lunch using real objects as well as neuropsychological tests. Group (young vs. old) by Condition (Passive Viewing vs. Verbalize Goal) ANOVAs were conducted to analyze eye tracking variables (i.e., fixation rate, number/duration of fixations to target/distractor objects and off objects). Both the younger and older adults made significantly fewer fixations to distractors during Verbalize Goal than Passive Viewing. Also, significant Group × Condition interactions were observed, indicating that younger adults, but not older adults, spent significantly more time viewing targets and less time off-objects in the goal driven, Verbalize Goal condition than the Passive Viewing condition. Goal-directed eye movements correlated with everyday action errors and tests of executive functioning. Taken together, results support theories of age-related decline in top-down cognitive control and indicate the potential utility of this eye tracking paradigm in detecting subtle age-related functional changes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Heterogeneity of Informant-Reported Functional Performance in Mild Cognitive Impairment: A Latent Profile Analysis of the Functional Activities Questionnaire

Heterogeneity of subtle functional difficulties in mild cognitive impairment (MCI) remains poorly understood. We characterized patterns of informant reports of functional abilities among participants with MCI and the relation between functional ability pattern and cognitive abilities and subsequent decline. Data from 4,273 MCI participants from the National Alzheimer's Coordinating Center (NACC) Uniform Data Set (UDS) were included in latent profile analyses (LPA) of informant responses on the Functional Activities Questionnaire (FAQ). Profiles from the best fitting model were compared on demographic, clinical, and cognitive variables. The best fitting model supported three profiles varying by level and type of difficulty: intact function (n = 3,299), intermediate (n = 769), and high ratings of difficulty (n = 205). For the Intermediate profile, items related to finances, remembering dates, and travel were rated as most difficult. The High Ratings profile also had elevated ratings on the meal preparation item. Participants with either the Intermediate or High Ratings profile demonstrated a three-fold increase in conversion to dementia as compared to participants with the Intact profile. Demographically, the Intact profile was younger and consisted of a higher proportion of minorities. On cognitive tests, the Intact profile showed the best performance, and the Intermediate profile performed comparably to or better than the High Ratings profile. There is meaningful heterogeneity in informant ratings of function in MCI, though individuals with MCI whose informants report even intermediate-level functional difficulties are more likely to progress to dementia, suggesting that even subtle functional difficulties place individuals at higher risk for future decline.

Naturalistic Assessment using a Simulated Environment: Cognitive Correlates and Relationship to Functional Status in Individuals with Neurologic Conditions

Objective

Research has shown that neurologic conditions, such as traumatic brain injury and multiple sclerosis, result in a number of cognitive and functional deficits. However, little is known about the relationship between various cognitive domains and ability to perform everyday activities. The Community Shopping Task (CST), a naturalistic assessment task conducted in a simulated environment, was used to examine functional abilities and cognitive correlates of everyday functioning in individuals with neurologic conditions.

Method

Thirty-four participants with neurologic conditions and 34 healthy controls completed the CST as well as traditional paper-pencil measures of cognition. In addition, all participants completed a questionnaire assessing instrumental activities of daily living (IADLs).

Results

The results indicated that participants with neurologic conditions required significantly more cues and time to complete the CST compared to control participants and that immediate memory and executive functioning were important predictors of CST performance. Furthermore, time to complete the CST accounted for a significant amount of variance in IADL performance, over and beyond the traditional measures of cognition.

Conclusions

These results provide evidence that a naturalistic task completed in an everyday environment can enhance our understanding of how daily functioning is impacted in individuals with neurologic conditions and subsequently inform rehabilitation strategies.

Independent and Differential Effects of Obesity and Hypertension on Cognitive and Functional Abilities

Objective

The primary aim of this study was to identify the independent and differential associations of obesity and hypertension with cognitive, physical, and directly observed functional abilities among middle age and older adults.

Method

Participants were 119 adults between the ages of 51 and 89, who underwent a cross-sectional assessment of cognitive, physical, functional and relevant health-related variables.

Results

Obesity predicted significantly poorer executive functions (β = -.301, t = -3.86, p < .001), mobility (β = .329, t = 3.59, p < .001), observed functional abilities (β = .220, t = 2.52, p = .013), and self-reported ability to perform activities of daily living that require physical capability (β = -.365, t = -4.23, p < .001). In contrast, hypertension was not independently associated with any of the outcome measures (ps > .05). Results from the path analysis revealed that executive functions mediated the association between obesity and poorer directly observed functional abilities. Additionally, obesity had a direct and indirect (through mobility) effect on self-reported basic activities of daily living.

Conclusions

These findings suggest a link between obesity, executive functions, and limitations in physical function and instrumental activities of daily living among middle age and older adults, however, longitudinal research is needed to further delineate the trajectory of these factors.

Differential Contributions of Selective Attention and Sensory Integration to Driving Performance in Healthy Aging and Alzheimer's Disease

OBJECTIVES

Patients with Alzheimer's disease (AD) demonstrate deficits in cross-cortical feature binding distinct from age-related changes in selective attention. This may have consequences for driving performance given its demands on multisensory integration. We examined the relationship of visuospatial search and binding to driving in patients with early AD and elderly controls (EC).

METHODS

Participants (42 AD; 37 EC) completed search tasks requiring either luminance-motion (L-M) or color-motion (C-M) binding, analogs of within and across visual processing stream binding, respectively. Standardized road test (RIRT) and naturalistic driving data (CDAS) were collected alongside clinical screening measures.

RESULTS

Patients performed worse than controls on most cognitive and driving indices. Visual search and clinical measures were differentially related to driving behavior across groups. L-M search and Trail Making Test (TMT-B) were associated with RIRT performance in controls, while C-M binding, TMT-B errors, and Clock Drawing correlated with CDAS performance in patients. After controlling for demographic and clinical predictors, L-M reaction time significantly predicted RIRT performance in controls. In patients, C-M binding made significant contributions to CDAS above and beyond demographic and clinical predictors. RIRT and C-M binding measures accounted for 51% of variance in CDAS performance in patients.

CONCLUSIONS

Whereas selective attention is associated with driving behavior in EC, cross-cortical binding appears most sensitive to driving in AD. This latter relationship may emerge only in naturalistic settings, which better reflect patients' driving behavior. Visual integration may offer distinct insights into driving behavior, and thus has important implications for assessing driving competency in early AD. (JINS, 2018, 24, 486-497).

The diary of a nonagenarian-centenarian woman with dementia: Memory loss, life changes, and community care in Japan

AIM

This study aimed to explore the experiences and thoughts of a nonagenarian-centenarian woman with dementia living alone, through detailed analysis of her unsolicited diary.

DATA SOURCE

After receiving consent from Aki (a pseudonym), her family and caregivers, copies of her diaries, hand-written in Japanese, were provided for analysis.

METHODS

The content of the diaries was broadly organized into themes and qualitative content analysis carried out for each theme along a sequential timeline. Changes in perspective, expression, quality of script, and frequency of notations were noted over time are compared with clinical assessments of dementia and activities of daily living recorded by health care providers. Demographic history was obtained from family members.

RESULTS

On recommendation by her nursing care manager, Aki began keeping a diary. By age 99, Aki was widowed and noted: "I'm lonely by myself." but still expressed hope: "I won't give up on myself." Concerning memory loss, she wrote: "I've already forgotten what happened this afternoon," and "I'll do things for myself." Regarding dependence, she said: "I get help from my children and others outside the family." And commented on the home care staff: "I don't know if they've come to help." "Is it someone I know well?" Although she thought that they took her belongings, she wrote: "I'll try not to forget to be grateful to them."

DISCUSSION

The diaries show that even as the dementia progressed, Aki was aware of her cognitive decline compounded by family losses. She used the diary as a coping method and to address relationships with family and caregivers.

Multiple Types of Memory and Everyday Functional Assessment in Older Adults

Objective

Current proxy measures for assessing everyday functioning (e.g., questionnaires, performance-based measures, and direct observation) show discrepancies in their rating of functional status. The present study investigated the relationship between multiple proxy measures of functional status and content memory (i.e., memory for information), temporal order memory, and prospective memory in an older adult sample.

Method

A total of 197 community-dwelling older adults who did (n = 45) or did not meet (n = 152) criteria for mild cognitive impairment (MCI), completed six different assessments of functional status (two questionnaires, two performance-based tasks, and two direct observation tasks) as well as experimental measures of content memory, prospective memory, and temporal order memory.

Results

After controlling for demographics and content memory, the temporal order and prospective memory measures explained a significant amount of variance in all proxy functional status measures. When all variables were entered into the regression analyses, content memory and prospective memory were found to be significant predictors of all measures of functional status, whereas temporal order memory was a significant predictor for the questionnaire and direct observation measures, but not performance-based measures.

Conclusion

The results suggest that direct observation and questionnaire measures may be able to capture components of everyday functioning that require context and temporal sequencing abilities, such as multi-tasking, that are not as well captured in many current laboratory performance-based measures of functional status. Future research should aim to inform the development and use of maximally effective and valid proxy measures of functional ability.

Polymorphisms in cytokine genes influence cognitive and functional performance in a population aged 75 years and above

OBJECTIVE

To investigate the frequency of the cytokine single nucleotide polymorphisms (SNPs) tumor necrosis factor (TNF)-α -308G > A, tumor growth factor (TGF)-β1 codon +10C > T, TGF-β1 codon +25G > C, interleukin (IL)-10 -1082A > G, IL-10 -819C > T, IL-10 -592C > A, IL-6 -174G > C, and IFN-γ +874T > A in a sample of healthy and cognitively impaired elderlies and to verify the probable association between these SNPs and cognitive and functional performance of subjects aged 75 years and above.

METHODS

259 Brazilian subjects were included, comprising 81 with cognitive impairment no dementia (CIND) and 54 demented seniors (together made up the cognitively impaired group, CI) and 124 age-matched and gender-matched cognitively healthy controls (CHS). The genotyping was performed by multiplex polymerase chain reaction. The cognitive performance was evaluated by Mini-Mental State Examination Brief Cognitive Screening Battery. The functional performance was accessed by Functional Activities Questionnaire.

RESULTS

The CC^lower genotype of TGF-β1 codon +25G > C was frequent in both patient groups. The TT^higher genotype of INF-γ +874T > A was less frequent in the dementia group. IL-10 haplotypes of lower expression were more frequent among CIND and demented patients. In CI, individuals with genetic variants that produce higher expression of TGF-β1, INF-γ, and IL-10 showed better normalized cognitive performance. Additionally, the A^lower allele of INF-γ +874T > A was related to worse functional performance in CI, while the A^lower allele of TNF-α -308G > A was associated with better cognitive and functional scores in the CIND group.

CONCLUSIONS

Our findings suggest a potential role for certain cytokine SNPs in the development of CIND and dementia, which may influence the functional and cognitive performance of these patients. Copyright © 2016 John Wiley & Sons, Ltd.

Embedded Online Questionnaire Measures Are Sensitive to Identifying Mild Cognitive Impairment

BACKGROUND/AIMS

Early changes in cognitively demanding daily activities occur between normal cognition and the development of mild cognitive impairment (MCI). These real-world functional changes as early signals of cognitive change form a prime target for meaningful early detection of dementia. We examined whether passive aspects of responding to a remotely monitored weekly online questionnaire discriminated between older adults with and without MCI.

METHODS

Participants were 83 independent, community-dwelling older adults enrolled in a longitudinal study of in-home monitoring technologies, which included completion of a short weekly online questionnaire of health and life events.

RESULTS

In longitudinal analyses, time to complete the online questionnaire decreased over 1 year in both MCI and cognitively intact participants (P<0.01). MCI and intact participants did not differ in the time of day they submitted their questionnaires initially; however, over the course of 1 year MCI participants began to submit their questionnaires progressively later in the day and they needed greater assistance from staff as compared with intact participants (P<0.05). The online questionnaire performance measures were significantly correlated to conventional cognitive test scores (P<0.05) across the spectrum of normal cognition to MCI.

CONCLUSIONS

Ambiently assessed, passive performance measures embedded within an online questionnaire are able to discriminate between normal cognition and MCI. Remote monitoring of cognitively demanding routine daily activities is a promising approach for ecologically valid real-world cognitive assessment.

Racial Differences in Neurocognitive Outcomes Post-Stroke: The Impact of Healthcare Variables

OBJECTIVES

The present study examined differences in neurocognitive outcomes among non-Hispanic Black and White stroke survivors using the NIH Toolbox-Cognition Battery (NIHTB-CB), and investigated the roles of healthcare variables in explaining racial differences in neurocognitive outcomes post-stroke.

METHODS

One-hundred seventy adults (91 Black; 79 White), who participated in a multisite study were included (age: M=56.4; SD=12.6; education: M=13.7; SD=2.5; 50% male; years post-stroke: 1-18; stroke type: 72% ischemic, 28% hemorrhagic). Neurocognitive function was assessed with the NIHTB-CB, using demographically corrected norms. Participants completed measures of socio-demographic characteristics, health literacy, and healthcare use and access. Stroke severity was assessed with the Modified Rankin Scale.

RESULTS

An independent samples t test indicated Blacks showed more neurocognitive impairment (NIHTB-CB Fluid Composite T-score: M=37.63; SD=11.67) than Whites (Fluid T-score: M=42.59, SD=11.54; p=.006). This difference remained significant after adjusting for reading level (NIHTB-CB Oral Reading), and when stratified by stroke severity. Blacks also scored lower on health literacy, reported differences in insurance type, and reported decreased confidence in the doctors treating them. Multivariable models adjusting for reading level and injury severity showed that health literacy and insurance type were statistically significant predictors of the Fluid cognitive composite (p<.001 and p=.02, respectively) and significantly mediated racial differences on neurocognitive impairment.

CONCLUSIONS

We replicated prior work showing that Blacks are at increased risk for poorer neurocognitive outcomes post-stroke than Whites. Health literacy and insurance type might be important modifiable factors influencing these differences. (JINS, 2017, 23, 640-652).

Longitudinal Trajectories of Informant-Reported Daily Functioning in Empirically Defined Subtypes of Mild Cognitive Impairment

OBJECTIVES

Within the Alzheimer's Disease Neuroimaging Initiative (ADNI)'s mild cognitive impairment (MCI) cohort, we previously identified MCI subtypes as well as participants initially diagnosed with MCI but found to have normal neuropsychological, biomarker, and neuroimaging profiles. We investigated the functional change over time in these empirically derived MCI subgroups.

METHODS

ADNI MCI participants (n=654) were classified using cluster analysis as Amnestic MCI (single-domain memory impairment), Dysnomic MCI (memory+language impairments), Dysexecutive/Mixed MCI (memory+language+attention/executive impairments), or Cluster-Derived Normal (CDN). Robust normal control participants (NCs; n=284) were also examined. The Functional Activities Questionnaire (FAQ) was administered at baseline through 48-month follow-up. Multilevel modeling examined FAQ trajectories by cognitive subgroup.

RESULTS

The Dysexecutive/Mixed group demonstrated the fastest rate of decline across all groups. Amnestic and Dysnomic groups showed steeper rates of decline than CDNs. While CDNs had more functional difficulty than NCs across visits, both groups' mean FAQ scores remained below its suggested cutoff at all visits.

CONCLUSIONS

Results (a) show the importance of executive dysfunction in the context of other impaired cognitive domains when predicting functional decline in at-risk elders, and (b) support our previous work demonstrating that ADNI's MCI criteria may have resulted in false-positive MCI diagnoses, given the CDN's better FAQ trajectory than those of the cognitively impaired MCI groups. (JINS, 2017, 23, 521-527).

Mild Cognitive Impairment and Changes in Everyday Function Over Time: The Importance of Evaluating Both Speed and Accuracy

OBJECTIVES

Research estimates that a significant percentage of individuals with mild cognitive impairment (MCI) experience functional difficulties. In addition to reduced accuracy on measures of everyday function, cross-sectional research has demonstrated that speed of performing instrumental activities of daily living (IADLs) is slowed in individuals with MCI. The present study investigated whether baseline and longitudinal changes in speed and accuracy of IADL performance differed between persons with MCI and cognitively normal peers.

DESIGN

Linear mixed models were used to estimate the group differences in longitudinal performance on measures of IADLs.

SETTING

Assessments were conducted at university and medical research centers.

PARTICIPANTS

The sample consisted of 80 participants with MCI and 80 control participants who were enrolled in the Alzheimer's Disease Research Center's Measuring Independent Living in the Elderly Study.

MEASUREMENTS

Instrumental activities of daily living speed and accuracy were directly assessed using selected domains of the Financial Capacity Instrument, the Timed IADL assessment, and driving-related assessments (Useful Field of View, Road Sign Test).

RESULTS

Individuals with MCI performed worse on speed and accuracy measures of IADLs in comparison to cognitively normal peers and demonstrated significantly steeper rates of decline over three years in either speed or accuracy in all domains assessed.

CONCLUSION

Both speed and accuracy of performance on measures of IADL are valuable indices for early detection of functional change in MCI. The performance pattern may reflect a trade-off between speed and accuracy that can guide clinical recommendations for maintaining patient independence.

Positive and Negative Consequences of Making Coffee among Breakfast Related Irrelevant Objects: Evidence from MCI, Dementia, and Healthy Ageing

OBJECTIVES

Previous studies have reported impairments in activities of daily living (ADL) performance in the presence of irrelevant but physically/functionally related objects in dementia patients. The aim of the present study was to increase our knowledge about the impact of the presence of contextually related non-target objects on ADL execution in patients with multi-domain mild cognitive impairment (MCI) and dementia.

METHODS

We compared ADL execution in patients with MCI, dementia, and healthy elderly participants under two experimental conditions: One in which the target objects were embedded with contextually related non-target items that constituted the object set necessary to complete two additional (but unrequired) ADL tasks related to the target task, and a second, control condition where target objects were surrounded by isolated objects (they never constituted a whole set needed to complete an alternative ADL task).

RESULTS

Separate analysis of ADL errors associated with the target task versus errors involving the non-target objects revealed that, although the presence of contextually related objects facilitated the accomplishment of the target task, such a condition also led to errors involving the use of irrelevant objects in dementia and MCI.

CONCLUSIONS

The presence of contextually related non-target items produces both positive and negative effects on ADL performance. These types of non-target objects might help to cue the retrieval of the action schema related to the target task, particularly in patients with MCI. In contrast, the presence of these objects might also lead to distraction in dementia and MCI. (JINS, 2017, 23, 481-492).

Characterising omission errors in everyday task completion and cognitive correlates in individuals with mild cognitive impairment and dementia

OBJECTIVE

Functional ability declines with age and cognitive impairment. This study investigated errors of omission made by community-dwelling older adults completing everyday tasks in a naturalistic setting.

METHOD

Sixty-five cognitively healthy older adults (HOA), 19 individuals with single domain mild cognitive impairment (sdMCI), 33 individuals with multi-domain MCI (mdMCI), and 13 individuals with dementia completed measures of memory, processing speed, working memory, and executive functioning, as well as eight different activities of daily living in a naturalistic environment. Task steps were divided into preparatory, action-oriented, and concluding steps.

RESULTS

For action-oriented steps, the number of omission errors increased with level of cognitive impairment beyond sdMCI (i.e., HOA = sdMCI < mdMCI < dementia). In contrast, for preparatory and concluding steps, the dementia group committed more omission errors than the HOA, sdMCI, and mdMCI groups, which did not differ.

CONCLUSIONS

The results suggest that the more complex and integrative action-oriented steps may be the first type of everyday task step to be affected in the process of cognitive decline, with preparatory and concluding steps being preserved longer and only showing decline in later stages of impairment (i.e., dementia). Individuals with sdMCI may use other intact abilities to compensate for task omission errors.

Mobility and Upright Posture Are Associated with Different Aspects of Cognition in Older Adults

Objectives: Aging is associated with cognitive decline, including visuomotor and memory concerns, and with motor system changes, including gait slowing and stooped posture. We investigated the associations of visuomotor performance and episodic memory with motor system characteristics in healthy older adults. Methods: Neurologically healthy older adults (N = 160, aged 50-89) completed a battery of cognitive and motor tasks. Cognitive variables were grouped by principal components analysis (PCA) into two components: visuomotor performance and verbal episodic memory. Our primary predictor variables were two aspects of motor function: timed-up-and-go (TUG) speed and neck angle. Additional predictor variables included demographic factors (age, sex and education) and indicators of physical fitness (body mass index/BMI and grip strength). All seven predictor variables were entered stepwise into a multiple regression model for each cognitive component. Results: Poor visuomotor performance was best predicted by a combination of advanced age, high BMI and slow TUG, whereas poor verbal memory performance was best predicted by a combination of advanced age, male sex, low education and acute neck angle. Conclusions: Upright posture and mobility were associated with different cognitive processes, suggesting different underlying neural mechanisms. These results provide the first evidence for a link between postural alignment and cognitive functioning in healthy older adults. Possible causal relationships are discussed.

One-Class Classification-Based Real-Time Activity Error Detection in Smart Homes

Caring for individuals with dementia is frequently associated with extreme physical and emotional stress, which often leads to depression. Smart home technology and advances in machine learning techniques can provide innovative solutions to reduce caregiver burden. One key service that caregivers provide is prompting individuals with memory limitations to initiate and complete daily activities. We hypothesize that sensor technologies combined with machine learning techniques can automate the process of providing reminder-based interventions. The first step towards automated interventions is to detect when an individual faces difficulty with activities. We propose machine learning approaches based on one-class classification that learn normal activity patterns. When we apply these classifiers to activity patterns that were not seen before, the classifiers are able to detect activity errors, which represent potential prompt situations. We validate our approaches on smart home sensor data obtained from older adult participants, some of whom faced difficulties performing routine activities and thus committed errors.

Functional Disability in Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

Accumulating evidence suggests that the pre-dementia syndrome mild cognitive impairment (MCI) is characterized by decrements in instrumental activities of daily living (IADL). The current review was a quantitative synthesis of the available literature to objectively characterize IADL disability in MCI while clarifying inconsistencies in findings across studies. It was hypothesized that individuals with MCI would display significantly greater functional impairment relative to cognitively intact controls. Candidate moderators specified a priori included functional assessment approach, MCI subtype, depressive symptoms, and language conducted. Online databases (PubMed/MEDLINE and PsycINFO) and reference lists were searched to identify peer-reviewed publications assessing IADL in MCI compared to normal aging. A total of 151 effect sizes derived from 106 studies met inclusionary criteria (N = 62,260). Random effects models yielded a large overall summary effect size (Hedges' g = 0.76, 95 % confidence interval: 0.68 - 0.83, p < .001) confirmed in multi-level analyses adjusted for nesting of effect sizes within studies (g = 0.78, 95 % confidence interval: 0.69 - 0.87). Functional assessment strategy and MCI subtype were significant moderators of effect size, whereas depressive symptoms and language were not. Results convincingly demonstrate that MCI is associated with significant difficulties in the performance of complex everyday tasks. It appears that functional decline, like cognitive decline, exists on a continuum from healthy aging to dementia onset. Implications for clinical practice and research priorities are discussed.

Automated Cognitive Health Assessment From Smart Home-Based Behavior Data

Smart home technologies offer potential benefits for assisting clinicians by automating health monitoring and well-being assessment. In this paper, we examine the actual benefits of smart home-based analysis by monitoring daily behavior in the home and predicting clinical scores of the residents. To accomplish this goal, we propose a clinical assessment using activity behavior (CAAB) approach to model a smart home resident's daily behavior and predict the corresponding clinical scores. CAAB uses statistical features that describe characteristics of a resident's daily activity performance to train machine learning algorithms that predict the clinical scores. We evaluate the performance of CAAB utilizing smart home sensor data collected from 18 smart homes over two years. We obtain a statistically significant correlation ( r=0.72) between CAAB-predicted and clinician-provided cognitive scores and a statistically significant correlation ( r=0.45) between CAAB-predicted and clinician-provided mobility scores. These prediction results suggest that it is feasible to predict clinical scores using smart home sensor data and learning-based data analysis.

Modeling Patterns of Activities using Activity Curves

Pervasive computing offers an unprecedented opportunity to unobtrusively monitor behavior and use the large amount of collected data to perform analysis of activity-based behavioral patterns. In this paper, we introduce the notion of an activity curve, which represents an abstraction of an individual's normal daily routine based on automatically-recognized activities. We propose methods to detect changes in behavioral routines by comparing activity curves and use these changes to analyze the possibility of changes in cognitive or physical health. We demonstrate our model and evaluate our change detection approach using a longitudinal smart home sensor dataset collected from 18 smart homes with older adult residents. Finally, we demonstrate how big data-based pervasive analytics such as activity curve-based change detection can be used to perform functional health assessment. Our evaluation indicates that correlations do exist between behavior and health changes and that these changes can be automatically detected using smart homes, machine learning, and big data-based pervasive analytics.