Role of executive functions in prospective memory in multiple sclerosis: Impact of the strength of cue–action association

Improving prospective memory in persons with multiple sclerosis via telehealth: A randomized feasibility study

BACKGROUND

Persons with multiple sclerosis (PwMS) can experience deficits in prospective memory (PM) or "remembering to remember," which are associated with functional difficulties. However, no cognitive rehabilitation intervention has specifically addressed improving PM in PwMS. The Telehealth PM Intervention (TPMI) provides a novel combination of two strategies-visual imagery and implementation intentions-that have each been beneficial in other populations. This study aimed to evaluate the feasibility of TPMI and its preliminary efficacy, which could be used to inform future trials.

METHODS

Participants (n = 35) were PwMS who were pre-screened and endorsed experiencing problems "remembering places they have to be" and "things they have to do." After completing a baseline evaluation, which included objective (Memory for Intentions Test; MIST) and subjective (Perceived Deficits Questionnaire; PDQ-PM) measures of PM, participants were randomized to either the active treatment (TPMI; n = 17) or active control group (Control; n = 18). TPMI was offered through remote one-on-one sessions twice a week over a four-week period. Participants were asked about treatment credibility and expectancy during the first session. The MIST and PDQ-PM were repeated at post-treatment, where treatment satisfaction was also captured. Mann-Whitney U and chi-square tests were used to examine the feasibility measures, while repeated measures ANOVAs were used to examine changes in the PM outcomes.

RESULTS

A total of 88.2 % of the TPMI group completed all eight sessions, with moderate-to-high (≥7 out of 10) treatment credibility/expectancy and satisfaction reported by 93.3 % and 86.7 %, respectively. While there were no significant effects on overall PM, the TPMI group had an improvement in objective time-based PM after adjusting for baseline differences (F(1,29) = 4.61, p = 0.040; d = 0.80). Furthermore, the TPMI group had a significant reduction in the number of time-based loss of content errors compared to the Control group, which remained significant after covariate adjustment (F(1,25) = 4.29, p = 0.049; d = 0.83).

CONCLUSIONS

TPMI is a feasible intervention, with high completion rates and moderate-to-high treatment ratings, that can be delivered remotely. Early evidence shows its potential benefit for improving time-based PM, a particular concern for PwMS, which should be further evaluated in a larger clinical trial.

Neuropsychiatric symptoms and metamemory across the life span: psychometric properties of the German Multifactorial Memory Questionnaire (MMQ)

OBJECTIVE

We assessed the psychometric properties, established normative data for the German Multifactorial Memory Questionnaire (MMQ), and analyzed its association with neuropsychiatric factors across the life span to provide a validated metamemory assessment for a German-speaking population.

METHODS

The three MMQ scales (memory satisfaction, self-rated ability, and strategy application) were translated into German, considering cultural, linguistic, and conceptual aspects. To validate the MMQ and assess associations with neuropsychiatric factors, the Complainer Profile Identification, Geriatric Depression Scale, Beck Anxiety Inventory, Pittsburgh Sleep Quality Index, and Short-Form-Health Survey were applied in an online study in 336 healthy participants with follow-up after 8 months.

RESULTS

Psychometric evaluation of the German MMQ showed normal distribution of all scales and good to excellent validity, internal consistency, and retest reliability. We provide percentiles and normative data for z-score conversion. Importantly, even subclinically elevated scores in depressiveness and anxiety were associated with decreased memory satisfaction and self-rated ability. Furthermore, although the influence of age on the German MMQ scales was minimal, effects of neuropsychiatric factors such as sleep quality, anxiety, and depressiveness on MMQ Satisfaction and Ability varied across the life span.

CONCLUSIONS

Our study provides a validated German translation of the MMQ with normative data and reliability measures, including reliable change scores. We show the impact of neuropsychiatric factors on the MMQ scales across the life span and emphasize the relevance of a multifactorial approach to metamemory as a measure of individualized everyday functionality and the importance of including neuropsychiatric factors into both research and clinical assessments of metamemory.

Patterns of prospective memory errors differ in persons with multiple sclerosis

INTRODUCTION

Prospective memory (PM) deficits have been documented in multiple sclerosis (MS). This study aimed to explore the specific types of errors made by persons with MS (PwMS), including differences between PwMS and healthy controls (HC) and PwMS who do and do not have impairments in processing speed and/or verbal learning and memory.

METHOD

PwMS (n = 111) and HC (n = 75) completed the Memory for Intentions Test (MIST), an objective measure of PM that has five types of errors that can be coded (PM failure, task substitution, loss of content, loss of time, and random errors). The number and types of PM errors were calculated for the overall MIST and six subscales, which break down performance by types of delay (2-Minute and 15-Minute), cue (Time and Event), and response (Verbal and Action). Impairment was defined as performing < 1.5 SD on either the Symbol Digit Modalities Test (SDMT) or Rey Auditory Verbal Learning Test (RAVLT). Bivariate analyses were used to examine group differences, with post-hoc pairwise comparisons with Bonferroni corrections.

RESULTS

Nearly 93% of PwMS made at least one PM error, compared to 76% of HC (V = .24, p = .001). The most commonly made PM error by PwMS was loss of content errors (45.0%). PwMS made significantly more task substitution errors (26.4% vs. 7.6%, p < .001) and fewer loss of time errors (9.5% vs. 21.2%, p < .001) than HC. Impaired PwMS made more errors than non-impaired PwMS, specifically PM failures on time-based tasks.

CONCLUSIONS

PM errors are common in PwMS, particularly when there are longer delays and time-based cues. Not only do PwMS make more errors than demographically similar HC, but they exhibit different cognitive process failures.

Relationship Between Future Thinking and Prospective Memory in Alzheimer's Disease

Background

Future thinking and prospective memory are two cognitive processes oriented toward the future and reliant on the ability to envision oneself in future scenarios.

Objective

We explored the connection between future thinking and prospective memory in individuals with Alzheimer's disease (AD).

Methods

We invited both AD participants and control participants to engage in event-based prospective memory tasks (e.g., "please hand me this stopwatch when I inform you there are 10 minutes remaining") and time-based prospective memory tasks (e.g., "close the book you are working on in five minutes"). Additionally, we asked participants to engage in a future thinking task where they imagined upcoming events.

Results

Analysis revealed that AD participants exhibited lower performance in both prospective memory tasks and future thinking compared to the control group. Importantly, we identified significant positive correlations between the performance on event- and time-based prospective memory tasks and future thinking abilities among AD participants.

Conclusions

These findings underscore the connection between the decline in both prospective memory domains and the ability to envision future events in individuals with AD. Our results also shed light on the challenges AD individuals face when trying to project themselves into the future to mentally pre-experience upcoming events.

Prospective memory in multiple sclerosis: clinical utility of the Miami Prospective Memory Test

Objective: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system that frequently affects cognition. Persons with MS (PwMS) complain of difficulties with prospective memory (PM), the capacity to remember to perform an intended action at the appropriate moment in the future. The objective of this study was to assess the clinical utility of the Miami Prospective Memory Test (MPMT) in detecting PM deficits in MS. The test is brief, easy to administer and accessible, and allows direct comparison between scores on event- and time-based conditions. A secondary objective was to examine the relationship between PM performance and cognitive functioning. Method: Eighty-four PwMS between 27 and 78 years old were compared to 50 age-, sex- and education-matched healthy adults on the MPMT. Results: Time-based (TB) scores, but not event-based (EB) scores, were significantly lower in PwMS than in healthy adults. The MPMT showed good internal consistency, and correlations were found with disability assessed by the Expanded Disability Status Scale (EDSS). PM was also correlated with memory and executive/attention functioning. Conclusions: This study supports the clinical utility of the MPMT in assessing the presence of PM deficits in PwMS especially under TB constraints.

Identifying prospective memory deficits in multiple sclerosis: Preliminary evaluation of the criterion and ecological validity of a single item version of the memory for intentions test (MIST)

Objectives: Difficulties with prospective memory (PM) are not routinely assessed in persons with multiple sclerosis (MS) even though they can impact daily functioning. This study aimed to examine the preliminary criterion and ecological validity of a highly abbreviated Memory for Intentions Test (MIST) intended to serve as an initial screening of PM in persons with MS. Methods: Participants (n = 112) were classified as impaired if they performed 1.5 standard deviations below the normative mean on the MIST. Individual MIST trials with adequate difficulty and discriminability were examined using receiver operating characteristic analyses, with their classification accuracies, sensitivities, and specificities compared to each other. Regressions were run to evaluate their ecological validity, with appointment attendance and employment as the outcomes. Results: Two trials had a classification accuracy of ≥80%: Trial 3 (79% sensitivity, 84% specificity) and Trial 4 (57% sensitivity, 91% specificity). These two trials had comparable specificity (p=.127), with Trial 3 having slightly higher sensitivity (p=.083). Only Trial 4 was significantly associated with appointment attendance (b = 1.63, p=.047) and unemployment (aOR = 11.20, p=.027). Discussion:Trial 4 of the MIST, a verbal task with a time-based cue that requires participants to complete a pre-specified response after a 15-minute delay, has the potential to be a screener for PM.

Prospective memory in adults with down syndrome

Prospective memory (PM) refers to the ability to remember one's intentions (what I must do), at the appropriate time, in the future (when I must do it). The objective of this work is to study the performance of people with Down syndrome (DS) compared to two control groups, matched by mental age and chronological age. For this purpose, an adapted version of the virtual week, which is an ecological test to simulate the functioning of PM in everyday life, was used. The results suggest that people with DS have difficulties in PM that mainly concern the binding (association) between prospective (when to do) and retrospective (what to do) components. Moreover, people with DS perform better in PM when the task is repeated and time-based. These results are discussed in light of studies conducted with other populations.

Time-Based Prospective Memory Is Associated with Functional Performance in Persons with MS

OBJECTIVE

Persons with multiple sclerosis (MS) often report prospective memory (PM) failures that directly impact their everyday life. However, it is not known whether PM deficits confer an increased risk of poorer everyday functioning. The aims of this study were to: (1) compare time- (Time-PM) and event-based PM (Event-PM) performance between persons with MS and healthy controls (HCs), (2) examine the neuropsychological correlates of PM in MS, and (3) examine the relationship between PM and everyday functioning in MS.

METHOD

A between-subjects design was used to examine 30 adults with MS and 30 community-dwelling HC. Participants were administered the Memory for Intentions Screening Test (MIST) to assess PM skills, the Actual Reality™ (AR) to assess everyday functioning, and a battery of cognitive tests.

RESULTS

The MS group performed significantly worse on Time-PM compared to HC but not on Event-PM tasks. While both Time-PM and Event-PM subscales were correlated with retrospective learning and memory, the MIST Time-PM subscale was correlated with executive functions. Significant correlations were observed between AR and the MIST Time-PM, but not Event-PM, subscales.

CONCLUSIONS

The results highlight the role of executive functions on Time-PM. Furthermore, significant relationships with AR extend the ecological validity of the MIST to MS populations.

High openness and high extroversion are linked with better time-based prospective memory in multiple sclerosis

BACKGROUND

Prospective memory (PM) deficits are often reported in multiple sclerosis (MS), but their relationship with neuropsychological characteristics and personality traits remains to be explored.

OBJECTIVE

To systematically investigate both time-based and event-based PM abilities in a sample of MS without clinically relevant disability or global cognitive decline and to explore cognitive, neuropsychiatric characteristics and personality traits associated with PM deficits.

METHODS

Thirty-three patients with MS and 33 healthy individuals were enrolled in the study. All participants underwent a standardized measure of PM to evaluate both time-based and event-based PM. Moreover, patients with MS completed the Brief Repeatable Battery to assess cognitive functioning, the Beck Depression Inventory-II and the Dimensional Apathy Scale to assess neuropsychiatric characteristics, and the NEO Personality Inventory-3 to assess personality traits.

RESULTS

Individuals with MS demonstrated impaired time-based PM compared to healthy individuals. The regression analysis showed that poor performance in time-based PM was significantly related to lower extroversion and openness traits, whereas poor performance in event-based PM was significantly related to lower visuospatial memory abilities.

CONCLUSIONS

Low levels of openness and extroversion traits are associated with a greater risk of developing time-based PM deficit. Therefore, personality assessment and behavioural interventions should be encouraged in MS clinical practice.

Comparison of the abbreviated minimal assessment of cognitive function in multiple sclerosis (aMACFIMS) and the brief international cognitive assessment for multiple sclerosis (BICAMS)

BACKGROUND

Cognitive impairment is a prevalent and often intrusive problem among persons with multiple sclerosis (PwMS). Valid and reliable assessments, including quick screening measures, are crucial. The Brief International Cognitive Assessment for MS (BICAMS) was developed for this reason. While it lends itself to use in locations where formal neuropsychological resources might be limited, it does not include measures of verbal fluency or executive functioning, domains assessed as part of the Minimal Assessment of Cognitive Function in MS (MACFIMS).

OBJECTIVE

Given previous evidence that shortened MACFIMS measures have strong criterion validity, this study aimed to determine which of these should be included in the abbreviated MACFIMS (aMACFIMS), and how the aMACFIMS compares to the BICAMS.

METHODS

One hundred forty-seven PwMS were included in the analyses. A stepwise logistic regression was used to determine the measures in the aMACFIMS. Receiver-operating-characteristic (ROC) curves assessed the classification accuracy, sensitivity, and specificity. The batteries' sensitivity, specificity, and predictive values were then compared.

RESULTS

Compared to the BICAMS, the final aMACFIMS had higher specificity (87% versus 72%) and positive predictive value (86% versus 77%), but lower sensitivity (71% versus 81%).

CONCLUSION

The aMACFIMS has several benefits, including reduced administration time and the addition of a verbal fluency/executive functioning measure.

Cognitive impairment in multiple sclerosis - a review of current knowledge and recent research

Multiple sclerosis (MS) is a chronic, progressive disease of the central nervous system that is characterised by inflammatory damage to the myelin sheath. Though often neglected, cognitive impairment is a common feature of MS that affects 43-70% of patients. It has a sophisticated neuroanatomic and pathophysiologic background and disturbs such vital cognitive domains as speed of information processing, memory, attention, executive functions and visual perceptual functions. In recent years there has been growing interest in neuroimaging findings with regard to cognitive impairment in MS. The possible options of managing cognitive dysfunction in MS are pharmacologic interventions, cognitive rehabilitation and exercise training; however, not enough evidence has been presented in this field. The aim of our article is to provide current knowledge on cognitive impairment in MS based on the most recent scientific results and conclusions with regard to affected cognitive domains, neuropsychological assessment, underlying mechanisms of this disturbance, neuroimaging findings and therapeutic options.

Google Calendar Enhances Prospective Memory in Alzheimer's Disease: A Case Report

We investigated whether an external memory aid (i.e., Google Calendar) would alleviate prospective memory compromise in a patient with mild Alzheimer's disease. The patient was asked in the baseline phase to perform three prospective targeted events (e.g., attending her weekly bridge game at the community club) and three prospective control events (e.g., buying her weekly magazine). The same six prospective events were assessed in the intervention phase but the targeted-events were cued by Google Calendar while the control-events were not. Results showed less omission of the targeted events in the training phase than in the baseline phase, suggesting a positive effect of Google Calendar. This case report offers a unique view into how smartphone calendars may alleviate prospective memory compromise in patients with mild Alzheimer's disease.

Negative Prospective Memory in Alzheimer's Disease: "Do Not Perform That Action"

Relatively to "standard" prospective memory, i.e., remembering to perform a future action, little is known about negative prospective memory, i.e., remembering not to perform a future action. This study investigated the latter ability in Alzheimer's disease (AD). AD participants and healthy older adults were asked to click on the keyboard or not to click on it when a cue word was encountered. Results showed more omissions (i.e., forgetting to click the keyboard when the instruction was to do so) in AD participants than in healthy older adults, suggesting a prospective memory deficit. Interestingly, more commissions (i.e., clicking the keyboard when the instruction was not to do so) were also observed in AD participants than in healthy older adults. Similar levels of commissions and omissions were observed in AD participants and in healthy older adults. Also, commissions and omissions were correlated with performance on an inhibition assessment task. Our findings reveal that AD is characterized by not only difficulty in the retrieval of recent information, but also difficulty to inhibit no-longer appropriate stimulus-response associations previously learned, suggesting a specific deficit of negative prospective memory in AD.

Prospective memory impairment in multiple sclerosis: a review

OBJECTIVE

Multiple sclerosis (MS) is a progressive disease of the central nervous system affecting information processing speed, episodic memory, attention, and executive functions. MS patients also often report prospective memory (PM) failures that directly impact their functional autonomy, including professional and social life. The purpose of this paper was to review the literature concerning the assessment and remediation of PM deficits in MS.

METHOD

The literature pertaining to PM impairment in MS was carefully reviewed using PubMed, PsyINFO, and Google Scholar, as well as cross-references from the articles published on this topic. Since PM rehabilitation in MS patients is still in its infancy, this review mainly focuses on studies that have directly assessed PM through various measures including questionnaires, standardized clinical tests, and experimental procedures.

CONCLUSION

This literature review confirms the presence of PM deficits in MS patients, even in the early stages of the disease. A further need for controlled studies on PM assessment and PM interventions in patients with MS is stressed.

Selective reminding of prospective memory in Multiple Sclerosis

OBJECTIVE

Multiple sclerosis (MS) is associated with prospective memory (PM) deficits, which may increase the risk of poor functional/health outcomes such as medication non-adherence. This study examined the potential benefits of selective reminding to enhance PM functioning in persons with MS.

METHOD

Twenty-one participants with MS and 22 healthy adults (HA) underwent a neuropsychological battery including a Selective Reminding PM (SRPM) experimental procedure. Participants were randomly assigned to either: (1) a selective reminding condition in which participants learn (to criterion) eight prospective memory tasks in a Selective Reminding format; or (2) a single trial encoding condition (1T).

RESULTS

A significant interaction was demonstrated, with MS participants receiving greater benefit than HAs from the SR procedure in terms of PM performance. Across diagnostic groups, participants in the SR conditions (vs. 1T conditions) demonstrated significantly better PM performance. Individuals with MS were impaired relative to HAs in the 1T condition, but performance was statistically comparable in the SR condition.

CONCLUSIONS

This preliminary study suggests that selective reminding can be used to enhance PM cue detection and retrieval in MS. The extent to which selective reminding of PM is effective in naturalistic settings and for health-related behaviours in MS remains to be determined.