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Background: Functional impairments are a necessary requirement for the diagnosis of a dementia along with observed cognitive impairment. Comparatively, functional abilities are often relatively intact in those with mild cognitive impairment (MCI). Objective: The current research examined the associations between memory clinic participants classified as cognitively intact, amnestic MCI, and mixed/dysexecutive MCI, using Jak-Bondi criteria, and Instrumental Activities of Daily Living - Compensation Scale (IADL-C) abilities, an informant-based questionnaire that quantifies functional abilities. The associations between functional abilities as assessed with the IADL-C and performance on neuropsychological tests were also investigated. Methods: IADLC scores were obtained along with a comprehensive neuropsychological protocol on memory clinic participants (n = 100) classified as cognitively normal (CN), amnestic MCI (aMCI), or a combined mixed/dysexecutive (mixed/dys) MCI. Regression analyses were employed to determine how the IADLC related to neuropsychological test performance. Results: On the IADLC, greater functional impairment was commonly observed in the mixed/dys MCI group compared to CN participants. Furthermore, the mixed/dys MCI group had lower scores on activities such as Money and Self-Management, Travel and Event Memory subscales compared to the CN group. Linear regression analyses found greater functional impairment in relation to lower scores on executive and episodic memory tests. Conclusions: Greater functional impairment as assessed with the IADL-C appears to be disproportionately associated with dysexecutive difficulty, and to a lesser degree, episodic memory. [ABSTRACT FROM AUTHOR]

Although executive functioning (EF) correlates with execution of instrumental activities of daily living (IADLs), tests of EF have been criticized for having poor ecological validity. Attempts have been made to develop new tests that approximate naturalistic daily tasks. However, the incremental utility of such tests has not been convincingly demonstrated. The Night Out Task (NOT) is a novel measure designed to increase ecological validity. This study examined whether the NOT correlates with traditional lab- and home-based measures of EF and IADLs, and whether it outperforms traditional measures of EF in predicting IADLs. Participants (50 adults aged 60 to 95) completed (1) the Delis Kaplan Executive Function System (D-KEFS) and IADLs in the laboratory, and (2) ecological momentary assessment of EF and daily IADL tasks at home across three weeks (using the Daily Assessment of Independent Living and Executive Skills protocol; DAILIES). The NOT correlated with a lab-based measure of EF beyond covariates, and lab-based IADLs beyond covariates and beyond the D-KEFS. However, it was unrelated to at-home variables beyond covariates. In contrast, the D-KEFS was a significant predictor of at-home IADLs, and this association was mediated by at-home EF performance. This study provides a preliminary validation of the NOT as a correlate of office-based performances in a primarily college educated white sample. Despite its high face validity, the NOT does not appear to sufficiently tap EF processes needed for home-based IADLs as measured by the DAILIES, although small sample size limits the interpretability of this negative finding. [ABSTRACT FROM AUTHOR]

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). 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). 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. 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. [ABSTRACT FROM AUTHOR]

Objective: Planning, a higher order executive functioning ability important for accomplishing complex everyday tasks, can be differentiated into initial and concurrent (online) planning. In this study, initial plans were codified to assess their impact on task execution. Cognitive correlates of initial planning and task execution were also examined. Method: One-hundred fifty-four community dwelling older adults completed a naturalistic task, called the Day Out Task (DOT), in either a planning or no planning condition. The DOT required participants to multitask and efficiently complete a series of eight subtasks, preparing for a hypothetical day out. Participants also completed a neuropsychological battery with the following cognitive constructs assessed: processing speed, cognitive flexibility, episodic memory, visuoconstructional abilities, and working memory and sequencing. Results: There were no significant differences between the planning and no planning conditions in DOT execution accuracy, efficiency or duration. However, efficiency of the initial plan was a significant predictor of task execution efficiency and initial plans that contained a higher amount of Task Relevant Associations predicted a shorter duration of task execution after controlling for age, processing speed and episodic memory. Furthermore, initial plans that had more Task Relevant Associations and task executions that took less time were associated with better working memory and sequencing ability. Discussion: Quality of the initial plan is important. Initial plans that organize task objectives in an efficient manner may lead to better task execution efficiency, while initial plans that demonstrate a detailed understanding of individual relational aspects of the tasks (i.e., higher rate of Task Relevant Associations) may result in faster task execution. [ABSTRACT FROM AUTHOR]

Everyday functioning and its executive functioning cognitive correlates (i.e., switching, inhibition, and updating) were investigated in healthy older adults (HOAs) using multiple methods of functional status. In addition to whether computerized experimental tasks would better dissociate these subcomponents than neuropsychological measures of executive functioning, we were also interested in the contributions of both experimental and neuropsychological measures of executive function subcomponents to functional abilities. Seventy HOAs (45 young-old and 25 old-old) and 70 younger adults completed executive function and neuropsychological tests. In addition to self- and informant questionnaires of functional abilities, HOAs completed two performance-based measures. An aging effect was found on all executive function measures. Old-old older adults and their informants did not report more functional difficulties but demonstrated more difficulties on performance-based measures than did young-old participants. For the HOAs, after controlling for age and education, the neuropsychological measures of executive functioning, but not experimental measures, explained a significant amount of variance in the informant-report and both performance-based measures. Updating measures differentially predicted performance-based measures, while switching was important for questionnaire and performance-based measures. The contribution of executive functioning to functional status when measured with experimental measures specifically designed to isolate the executive subcomponent was not as strong as hypothesized. Further research examining the value of isolating executive function subcomponents in neuropsychological assessment and the prediction of functional abilities in older adults is warranted. [ABSTRACT FROM PUBLISHER]

Introduction: The use of compensatory strategies plays an important role in the ability of older adults to adapt to late-life memory changes. Even with the benefits associated with compensatory strategy use, little research has explored specific mechanisms associated with memory performance and compensatory strategies. Rather than an individual’s objective memory performance directly predicting their use of compensatory strategies, it is possible that some other variables are indirectly influencing that relationship. The purpose of this study was to: (a) examine the moderating effects of cognitive reserve (CR) and (b) evaluate the potential mediating effects of memory self-efficacy on the relationship between objective memory performance and compensatory strategy use.Method: Two structural equation models (SEM) were used to evaluate CR (latent moderator model) and memory self-efficacy (mediator model) in a sample of 155 community-dwelling older adults over the age of 55.Results: The latent variable moderator model indicated that CR was not substantiated as a moderator variable in this sample (p= .861). However, memory self-efficacy significantly mediated the association between objective memory performance and compensatory strategy use (β = .22, 95% confidence interval, CI [.002, .437]). More specifically, better objective memory was associated with lower compensatory strategy use because of its relation to higher memory self-efficacy.Conclusions: These findings provide initial support for an explanatory framework of the relation between objective memory and compensatory strategy use in a healthy older adult population by identifying the importance of an individual’s memory perceptions. [ABSTRACT FROM PUBLISHER]

Objective: Within-person variability in cognitive performance is related to neurological integrity, but the association with functional abilities is less clear. The primary aim of this study was to examine the association between cognitive dispersion, or within-person variability, and everyday multitasking and the way in which these variables may influence performance on a naturalistic assessment of functional abilities. Method: Participants were 156 community-dwelling adults, age 50 or older. Cognitive dispersion was calculated by measuring within-person variability in cognitive domains, established through principal components analysis. Path analysis was used to determine the independent contribution of cognitive dispersion to functional ability, mediated by multitasking. Results: Results of the path analysis revealed that the number of subtasks interweaved (i.e., multitasked) mediated the association between cognitive dispersion and task sequencing and accuracy. Although increased multitasking was associated with worse task performance in the path model, secondary analyses revealed that for individuals with low cognitive dispersion, increased multitasking was associated with better task performance, whereas for those with higher levels of dispersion multitasking was negatively correlated with task performance. Conclusion: These results suggest that cognitive dispersion between domains may be a useful indicator of multitasking and daily living skills among older adults. [ABSTRACT FROM AUTHOR]

Introduction: Reducing the amount of testing required to accurately detect cognitive impairment is clinically relevant. The aim of this research was to determine the fewest number of clinical measures required to accurately classify participants as healthy older adult, mild cognitive impairment (MCI), or dementia using a suite of classification techniques.Method: Two variable selection machine learning models (i.e., naive Bayes, decision tree), a logistic regression, and two participant datasets (i.e., clinical diagnosis; Clinical Dementia Rating, CDR) were explored. Participants classified using clinical diagnosis criteria included 52 individuals with dementia, 97 with MCI, and 161 cognitively healthy older adults. Participants classified using CDR included 154 individuals with CDR = 0, 93 individuals with CDR = 0.5, and 25 individuals with CDR = 1.0+. A total of 27 demographic, psychological, and neuropsychological variables were available for variable selection.Results: No significant difference was observed between naive Bayes, decision tree, and logistic regression models for classification of both clinical diagnosis and CDR datasets. Participant classification (70.0–99.1%), geometric mean (60.9–98.1%), sensitivity (44.2–100%), and specificity (52.7–100%) were generally satisfactory. Unsurprisingly, the MCI/CDR = 0.5 participant group was the most challenging to classify. Through variable selection only 2–9 variables were required for classification and varied between datasets in a clinically meaningful way.Conclusions: The current study results reveal that machine learning techniques can accurately classify cognitive impairment and reduce the number of measures required for diagnosis. [ABSTRACT FROM PUBLISHER]

Introduction: Deficits in attentional abilities can significantly impact rehabilitation and recovery from traumatic brain injury (TBI). This study investigated the nature and recovery of preattentive (parallel) and attentive (serial) visual search abilities after TBI. Method: Participants were 40 individuals with moderate to severe TBI who were tested following emergence from posttraumatic amnesia and approximately 8 months post injury, as well as 40 age- and education-matched controls. Preattentive (automatic) and attentive (controlled) visual search situations were created by manipulating the saliency of the target item amongst distractor items in visual displays. The relationship between preattentive and attentive visual search rates and follow-up community integration were also explored. Results: The results revealed intact parallel (automatic) processing skills in the TBI group both postacutely and at follow-up. In contrast, when attentional demands on visual search were increased by reducing the saliency of the target, the TBI group demonstrated poorer performances than the control group both postacutely and 8 months post injury. Neither preattentive nor attentive visual search slope values correlated with follow-up community integration. Conclusions: These results suggest that utilizing intact preattentive visual search skills during rehabilitation may help to reduce high mental workload situations, thereby improving the rehabilitation process. For example, making commonly used objects more salient in the environment should increase reliance or more automatic visual search processes and reduce visual search time for individuals with TBI. [ABSTRACT FROM AUTHOR]

Introduction:There is currently limited research evaluating planning abilities, a core subcomponent of executive functioning, in individuals with mild cognitive impairment (MCI). In the present study, we utilized the “Amap Task,” an open-ended problem-solving task, to separately evaluate the formulation and execution components of planning ability in individuals with MCI.Method:Thirty-seven cognitively healthy older adults and 37 individuals with MCI used a map layout of a university apartment to develop and write out a strategy (formulation stage) to successfully complete a list of tasks (e.g., retrieve and fill a water pitcher before placing it in the refrigerator). Subsequently, participants carried out the tasks in the apartment with the aid of their formulated plan (execution stage).Results:MCI participants performed more poorly than older adult (OA) controls during both the formulation and execution stages on measures of task accuracy and task efficiency. However, both groups were able to adjust and improve task accuracy and efficiency from formulation to task execution. Finally, MCI participants took significantly longer to complete the task and adhered less to their formulated plans during task completion.Conclusions:Using an open-ended problem-solving task, the findings revealed that individuals with MCI experienced difficulties with both the formulation and execution components of planning. Like controls, participants with MCI were able to successfully modify their plan online, improving their performance from task formulation to task execution. [ABSTRACT FROM PUBLISHER]

Traumatic brain injury (TBI) is associated with deficits in memory for the content of completed activities. However, TBI groups have shown variable memory for the temporal order of activities. We sought to clarify the conditions under which temporal order memory for activities is intact following TBI. Additionally, we evaluated activity source memory and the relationship between activity memory and functional outcome in TBI participants. Thus, we completed a study of activity memory with 18 severe TBI survivors and 18 healthy age- and education-matched comparison participants. Both groups performed eight activities and observed eight activities that were fashioned after routine daily tasks. Incidental encoding conditions for activities were utilized. The activities were drawn from two counterbalanced lists, and both performance and observation were randomly determined and interspersed. After all of the activities were completed, content memory (recall and recognition), source memory (conditional source identification), and temporal order memory (correlation between order reconstruction and actual order) for the activities were assessed. Functional ability was assessed via the Community Integration Questionnaire (CIQ). In terms of content memory, TBI participants recalled and recognized fewer activities than comparison participants. Recognition of performed and observed activities was strongly associated with social integration on the CIQ. There were no between- or within-group differences in temporal order or source memory, although source memory performances were near ceiling. The findings were interpreted as suggesting that temporal order memory following TBI is intact under conditions of both purposeful activity completion and incidental encoding, and that activity memory is related to functional outcomes following TBI. [ABSTRACT FROM AUTHOR]

An event-based nonfocal task was used to evaluate prospective memory (PM) and the relationship between PM, neuropsychological testing data, and everyday forgetting. Twenty-four participants with mild cognitive impairment (MCI) and 24 age- and education-matched cognitively healthy adults responded to a nonfocal PM cue, while completing an ongoing working memory task. Neuropsychological testing data and self- and informant-report of frequency of forgetting were also gathered. Compared to healthy adults, the MCI participants exhibited significantly poorer prospective remembering and ongoing task performance, despite similar self-reported effort directed to the PM task. Both self- and informant-report indicated that the MCI group was experiencing a higher frequency of everyday forgetting than the healthy adult group. Self-report of everyday forgetting was correlated with PM task performance for the healthy adults, but not for the MCI participants. For the healthy adults, correlational analyses also showed significant relationships between PM accuracy and tests of memory and executive functioning, suggesting that both spontaneous retrieval processes and effortful, strategic monitoring may be important in supporting prospective remembering for this nonfocal PM task. The stronger relationships between PM accuracy and memory and language tests for the MCI group suggest that their poorer event-based prospective remembering might be linked to impaired spontaneous retrieval processes, which are thought to be supported by medial temporal structures. [ABSTRACT FROM AUTHOR]

Planning ability, a subset of executive functioning, has been shown to decline with normal aging. However, the exact nature of this decline has yet to be adequately examined. In this study, 50 younger adults and 50 older adults completed a map task designed to tease apart the formulation and execution stages of planning. Participants were tasked with reading a map layout of a university apartment and planning an efficient route to complete several tasks. There were two conditions, aid and no-aid. During the formulation stage, participants wrote out their plan for later task completion. In the execution stage, half of the participants were instructed to utilize their written aid during task completion while the other half completed tasks without the use of their aid. Older adults performed more poorly than younger adults during both the formulation and execution stages on measures of accuracy and efficiency. There was no effect of using the aid during execution. Thus, using an open-ended planning task involving real-world stimuli, we found age-related deficits in planning ability associated with both the formulation and execution components, and not exclusively with formulation. We also found that both groups successfully updated and adjusted their formulated plans during execution. [ABSTRACT FROM AUTHOR]

Few studies have investigated the complex nature of everyday activity memory following traumatic brain injury (TBI). This study examined recovery of content and temporal order memory for performed activities during the first year in individuals who suffered moderate to severe TBI. TBI and control participants completed eight different cognitive activities at baseline (i.e., acutely following injury for TBI) and then again approximately one year later (follow-up). Participants' free recall of the activities provided a measure of content memory. Temporal order memory was assessed with a reconstruction task. Self-report and informant report of everyday memory problems at follow-up were used to examine the relationship between activity memory performances and everyday memory. TBI participants showed significant recovery in both content and temporal order memory for activities during the first year. Despite showing significant recovery, the TBI group's activity memory performances remained poorer than that of controls at follow-up. Greater self- and informant report of everyday memory difficulties was associated with poorer temporal order memory but not content memory for activities. These findings demonstrate recovery in multiple memory processes that support activity memory following moderate to severe TBI. The findings also suggest a stronger link between everyday memory abilities and temporal order memory for activities than activity memory content in a TBI population. [ABSTRACT FROM AUTHOR]

This study examined awareness of memory problems and memory self-monitoring abilities in individuals with Alzheimer's disease (AD). Participants were 20 individuals with AD and 20 older adult controls. A global performance-prediction paradigm, which required participants to predict the number of words they would remember both prior to and after completing a list-learning memory task, was used as the online assessment measure. Offline assessment of memory involved contrasting self-ratings provided by participants about the frequency of everyday memory failures with ratings from knowledgeable informants. As expected, participants with AD demonstrated poorer recall for the word list than did controls. Participants with AD were also less accurate than controls in their preexperience memory predictions, and findings from the offline assessment method similarly revealed that the AD group overestimated their everyday memory abilities. Despite showing impaired understanding of personal memory ability, the AD group successfully modified their postexperience memory predictions so that they were more accurate following task exposure, demonstrating accurate memory self-monitoring abilities. These findings highlight the complex and multidimensional nature of metamemory. The findings further suggest that while AD patients appear able to immediately benefit from task experience, they have difficulty creating lasting awareness of memory abilities. [ABSTRACT FROM AUTHOR]

We applied the item-specific deficit approach (ISDA) to California Verbal Learning Test data obtained from 56 severe, acceleration-deceleration closed head injury (CHI) participants and 62 controls. The CHI group demonstrated deficits on all ISDA indices in comparison to controls. Regression analyses indicated that encoding deficits, followed by consolidation deficits, accounted for most of the variance in delayed recall. Additionally, level of acquisition played a partial role in CHI-associated consolidation difficulties. Finally, CHI encoding deficits were largely driven by low semantic clustering during list learning. These results suggest that encoding (primary) and consolidation (secondary) deficits account for CHI-associated verbal memory impairment. [ABSTRACT FROM AUTHOR]

This study examined both retrospective and prospective memory self-monitoring abilities in 33 individuals with amnestic mild cognitive impairment (MCI) and 33 healthy older adult controls. Participants learned 36 critical cue-target word pairs. Following a distractor task, participants were asked to recall each target word that corresponded to a given cue word. Confidence ratings were provided for recalled words. For nonrecalled words, feeling-of-knowing judgments about the likelihood of recognizing the target word on a subsequent recognition test were provided. We found that despite poorer episodic memory performance, the MCI individuals demonstrated accurate retrospective self-monitoring of recalled episodic material. In contrast, the MCI participants were less accurate than controls prospectively self-monitoring their memory for newly learned information. These findings suggest that memory self-monitoring is not a unitary construct and that amnestic MCI participants have difficulty with prospective memory self-monitoring abilities. [ABSTRACT FROM AUTHOR]

A performance-prediction paradigm was used to examine metamemory abilities in 27 individuals with amnestic mild cognitive impairment (MCI), 14 individuals with nonamnestic MCI, and 41 controls. To assess memory self-awareness, participants predicted the number of words they would remember before completing a list-learning memory task. Memory self-monitoring was evaluated by participants' ability to increase the accuracy of their predictions after experience with the list-learning task. As expected, participants with amnestic MCI demonstrated poorer memory abilities than the controls and participants with nonamnestic MCI. The amnestic MCI group also correctly predicted that they would recall less information than controls. Furthermore, both MCI groups showed accurate awareness of how differing task demands influence recall and successfully modified their memory predictions to be more accurate following task exposure. These findings revealed that individuals with amnestic and nonamnestic MCI were able to competently assess the demands of an externally driven metamemorial situation and utilize experience with a task to accurately update memory self-knowledge. Accurate metamemory skills may facilitate the ability of individuals with MCI to benefit from targeted behavioral interventions focused on utilizing compensatory strategies for everyday memory problems. [ABSTRACT FROM AUTHOR]

In the current study, we introduce the Item-Specific Deficit Approach (ISDA), a novel method for characterizing memory process deficits in list-learning data. To meet this objective, we applied the ISDA to California Verbal Learning Test (CVLT) data collected from a sample of 132 participants (53 healthy participants and 79 neurologically compromised participants). Overall, the ISDA indices measuring encoding, consolidation, and retrieval deficits demonstrated advantages over some traditional indices and indicated acceptable reliability and validity. Currently, the ISDA is intended for experimental use, although further research may support its utility for characterizing memory impairments in clinical assessments. [ABSTRACT FROM AUTHOR]

We examined memory self-awareness and memory self-monitoring abilities during inpatient rehabilitation in participants with moderate to severe traumatic brain injury (TBI). A total of 29 participants with moderate to severe TBI and 29 controls matched on age, gender, and education completed a performance prediction paradigm. To assess memory self-awareness, participants predicted the amount of information they would remember before completing list-learning tasks and visual–spatial memory tasks. Memory self-monitoring was assessed by participants' ability to increase accuracy of their predictions after experience with the tests. Although the TBI participants performed more poorly than controls on both episodic memory tasks, no significant group differences emerged in memory self-awareness or memory self-monitoring. The TBI participants predicted that their memory performances would be poorer than that of controls, accurately adjusted their predictions in accordance with the demands of the tasks, and successfully modified their predictions following experience with the tasks. The results indicate that moderate to severe TBI individuals in the early stages of recovery can competently assess the demands of externally driven metamemorial situations and utilize experience with task to accurately update their knowledge of memory abilities. [ABSTRACT FROM AUTHOR]

The ability to accurately estimate the passage of time plays an important role in helping to structure daily activities. In this study, we used a prospective verbal time estimation paradigm to investigate time perception in 27 moderate to severe traumatic brain injury (TBI) participants and 27 controls. Verbal time estimations were made for filled intervals both within (i.e., <30 s) and beyond the time frame of working memory. We found that the TBI participants exhibited normal or near-normal estimates of time passage for duration up to 25 s. In contrast, for durations that exceeded working memory, the TBI group perceived less time as having passed than actually had passed as the TBI group significantly underestimated time when compared to controls. This pattern of data was interpreted as being due to episodic memory dysfunction. [ABSTRACT FROM AUTHOR]

Thirty severe closed-head injured (CHI) participants (more than 1 year postinjury ) and 30 matched controls completed eight different cognitive activities. Participants' free recall and recognition of the activities provided a measure of content memory. Temporal order memory was assessed with a reconstruction task. CHI participants recalled and recognized fewer activities than did controls. However, the CHI and control group did not differ in temporal order memory. For both groups, recognition memory was not correlated with temporal order memory. These results demonstrate intact temporal order memory for performed activities in a severe CHI population, and support the notion of separate processing of content memory and order information. Issues related to automaticity and the roles of the frontal in temporal order memory are also discussed. [ABSTRACT FROM AUTHOR]

This study investigated executive aspects of working memory in a severe closed-head injured (CHI) population. Thirty-four severe CHI participants (<1 postinjury) and 34 controls completed an abstract design version of petrides and Milner's (1982) self-ordered pointing task. CHI participants made more errors than controls on the 16-item trial, but not the 9-item trial. Both CHI and control participants were able to make use of strategic processing to improve SOPT performance. As anticipated, errors on the SOPT were associated with another measure of working memory (i.e., Reading Span Test) for the control group. In contrast for the CHI participants, error on the SOPT were associated with a measure of delayed visual memory (i.e., Wechsler Memory Scale - Revised Visual Reproduction II subtest). Our finding suggest that, as an group, the primary factor resulting in poorer SOPT performance by the CHI group was a memory deficit and not the ability to utilize executive aspects of working memory. [ABSTRACT FROM AUTHOR]