Reliability of a novel serious game using dual-task gait profiles to early characterize aMCI

The effects of exergames for cognitive function in older adults with mild cognitive impairment: a systematic review and metaanalysis

Purpose

Exergames are an innovative method that can promote neuroplasticity and improve the cognitive abilities of the elderly. This study aimed to compare the effects of single-task and multi-task exergames on the cognitive ability of the elderly with mild cognitive impairment (MCI).

Methods

Computerized literature search was performed using PubMed, Web of Science, EBSCO, Elsevier, ProQuest, China National Knowledge Infrastructure (CNKI), Wanfang and VIP database to identify relevant articles from the establishment of the database from inception to April 1, 2024. The inclusion criteria were: (i) participants aged 60 or older diagnosed with mild cognitive impairment, regardless of gender; (ii) use of randomized controlled trials (RCTs); (iii) interventions involving exergames with physical activity or as the primary variable; and (iv) outcome measures using standardized neuropsychological instruments to assess cognitive function, including statistical data on sample size, mean, and standard deviation. Finally, the included study comprised a total of 526 participants. Mean difference (MD) and 95% confidence interval (CI) were used to synthesize the effect size in the data.

Results

11 studies were included. Due to the differences in the intervention methods, subgroup analysis was performed on the included research. Compared with the control group assessed by the Montreal Cognitive Assessment Scale, the single-task intervention improved the cognitive ability of the elderly with MCI (MD 3.40, 95% CI 2.43-4.37), the Mini-Mental State Examination Scale (MD 2.38, 95% CI -2.03 to 2.72), the Trail Making Test (MD -3.89, 95% CI -6.45 to -1.33), and the Digit Span Forward test (MD 1.16, 95% CI 0.73-1.60).

Conclusion

This meta-analysis supports that exergames could be an effective cognitive rehabilitation method for MCI patients. Our study recommends that patients implement a customized exergames program and adhere to it for a long time. It is necessary to pay attention to the exercise guidelines and provide evidence from clinicians.

Strengths and limitations of this study

(1) This meta-analysis supports that exergames could be an effective cognitive rehabilitation method for MCI patients. Our study recommends that patients implement a customized exergames program and adhere to it for a long time. It is necessary to pay attention to the exercise guidelines and provide evidence from clinicians. (2) This research provides preliminary evidence for the clinical utility of VR tasks developed for mild cognitive impairment. (3) In this paper, only relevant studies in Chinese and English were searched, and no studies in other languages were searched.

Virtual Reality and Serious Videogame-Based Instruments for Assessing Spatial Navigation in Alzheimer's Disease: A Systematic Review of Psychometric Properties

Over the past decade, research using virtual reality and serious game-based instruments for assessing spatial navigation and spatial memory in at-risk and AD populations has risen. We systematically reviewed the literature since 2012 to identify and evaluate the methodological quality and risk of bias in the analyses of the psychometric properties of VRSG-based instruments. The search was conducted primarily in July-December 2022 and updated in November 2023 in eight major databases. The quality of instrument development and study design were analyzed in all studies. Measurement properties were defined and analyzed according to COSMIN guidelines. A total of 1078 unique records were screened, and following selection criteria, thirty-seven studies were analyzed. From these studies, 30 instruments were identified. Construct and criterion validity were the most reported measurement properties, while structural validity and internal consistency evidence were the least reported. Nineteen studies were deemed very good in construct validity, whereas 11 studies reporting diagnostic accuracy were deemed very good in quality. Limitations regarding theoretical framework and research design requirements were found in most of the studies. VRSG-based instruments are valuable additions to the current diagnostic toolkit for AD. Further research is required to establish the psychometric performance and clinical utility of VRSG-based instruments, particularly the instrument development, content validity, and diagnostic accuracy for preclinical AD screening scenarios. This review provides a straightforward synthesis of the state of the art of VRSG-based instruments and suggests future directions for research.

Cognitive-motor dual-task interference in Alzheimer's disease, Parkinson's disease, and prodromal neurodegeneration: A scoping review

BACKGROUND

Cognitive-motor interference (CMI) is a common deficit in Alzheimer's (AD) disease and Parkinson's disease (PD) and may have utility in identification of prodromal neurodegeneration. There is lack of consensus regarding measurement of CMI resulting from dual task paradigms.

RESEARCH QUESTION

How are individuals with AD, PD, and prodromal neurodegeneration impacted by CMI as measured by dual-task (DT) performance?

METHODS

A systematic literature search was performed in six datasets using the PRISMA guidelines. Studies were included if they had samples of participants with AD, PD, or prodromal neurodegeneration and reported at least one measure of cognitive-motor DT performance.

RESULTS

4741 articles were screened and 95 included as part of this scoping review. Articles were divided into three non-mutually exclusive groups based on diagnoses, with 26 articles in AD, 56 articles in PD, and 29 articles in prodromal neurodegeneration, and results presented accordingly.

SIGNIFICANCE

Individuals with AD and PD are both impacted by CMI, though the impact is likely different for each disease. We found a robust body of evidence regarding the utility of measures of DT performance in the detection of subtle deficits in prodromal AD and some signals of utility in prodromal PD. There are several key methodological challenges related to DT paradigms for the measurement of CMI in neurodegeneration. Overall, DT paradigms show good potential as a clinical method to probe specific brain regions, networks, and function; however, task selection and effect measurement should be carefully considered.

Dynamic Reconfiguration of Dominant Intrinsic Coupling Modes in Elderly at Prodromal Alzheimer's Disease Risk

Large-scale human brain networks interact across both spatial and temporal scales. Especially for electro- and magnetoencephalography (EEG/MEG), there are many evidences that there is a synergy of different subnetworks that oscillate on a dominant frequency within a quasi-stable brain temporal frame. Intrinsic cortical-level integration reflects the reorganization of functional brain networks that support a compensation mechanism for cognitive decline. Here, a computerized intervention integrating different functions of the medial temporal lobes, namely, object-level and scene-level representations, was conducted. One hundred fifty-eight patients with mild cognitive impairment underwent 90 min of training per day over 10 weeks. An active control (AC) group of 50 subjects was exposed to documentaries, and a passive control group of 55 subjects did not engage in any activity. Following a dynamic functional source connectivity analysis, the dynamic reconfiguration of intra- and cross-frequency coupling mechanisms before and after the intervention was revealed. After the neuropsychological and resting state electroencephalography evaluation, the ratio of inter versus intra-frequency coupling modes and also the contribution of β1 frequency was higher for the target group compared to its pre-intervention period. These frequency-dependent contributions were linked to neuropsychological estimates that were improved due to intervention. Additionally, the time-delays of the cortical interactions were improved in {δ, θ, α2, β1} compared to the pre-intervention period. Finally, dynamic networks of the target group further improved their efficiency over the total cost of the network. This is the first study that revealed a dynamic reconfiguration of intrinsic coupling modes and an improvement of time-delays due to a target intervention protocol.

Virtual reality and mental health in older adults: a systematic review

IMPORTANCE

Virtual reality (VR) is a promising tool with the potential to enhance care of cognitive and affective disorders in the aging population. VR has been implemented in clinical settings with adolescents and children; however, it has been less studied in the geriatric population.

OBJECTIVE

The objective of this study is to determine the existing levels of evidence for VR use in clinical settings and identify areas where more evidence may guide translation of existing VR interventions for older adults.

DESIGN AND MEASUREMENTS

We conducted a systematic review in PubMed and Web of Science in November 2019 for peer-reviewed journal articles on VR technology and its applications in older adults. We reviewed article content and extracted the number of study participants, study population, goal of the investigation, the level of evidence, and categorized articles based on the indication of the VR technology and the study population.

RESULTS

The database search yielded 1554 total results, and 55 articles were included in the final synthesis. The most represented study design was cross-sectional, and the most common study population was subjects with cognitive impairment. Articles fell into three categories for VR Indication: Testing, Training, and Screening. There was a wide variety of VR environments used across studies.

CONCLUSIONS

Existing evidence offers support for VR as a screening and training tool for cognitive impairment in older adults. VR-based tasks demonstrated validity comparable to some paper-based assessments of cognition, though more work is needed to refine diagnostic specificity. The variety of VR environments used shows a need for standardization before comparisons can be made across VR simulations. Future studies should address key issues such as usability, data privacy, and confidentiality. Since most literature was generated from high-income countries (HICs), it remains unclear how this may be translated to other parts of the world.

Virtual reality-based monitoring test for MCI: A multicenter feasibility study

OBJECTIVES

As the significance of the early diagnosis of mild cognitive impairment (MCI) has emerged, it is necessary to develop corresponding screening tools with high ecological validity and feasible biomarkers. Virtual reality (VR)-based cognitive assessment program, which is close to the daily life of the older adults, can be suitable screening tools for MCI with ecological validity and accessibility. Meanwhile, dehydroepiandrosterone (DHEA) has been observed at a low concentration in the older adults with dementia or cognitive decline, indicating its potential as a biomarker of MCI. This study aimed to determine the efficacy and usability of a VR cognitive assessment program and salivary DHEA for screening MCI.

METHODS

The VR cognitive assessment program and the traditional Montreal Cognitive Assessment (MOCA) test were performed on 12 patients with MCI and 108 healthy older adults. The VR program operates in a situation of caring for a grandchild, and evaluates the memory, attention, visuospatial, and executive functions. An analysis of covariance (ANCOVA), a partial correlation analysis, and receiving operating characteristic (ROC) curve analysis were conducted for statistical analysis.

RESULTS

According to the ANCOVA, no significant difference in MOCA scores was found between the normal and MCI groups (F = 2.36, p = 0.127). However, the VR total score of the MCI group was significantly lower than that of the normal group (F = 8.674, p = 0.004). There was a significant correlation between the MOCA and VR scores in the total and matched subdomain scores. The ROC curve analysis also showed a larger area under the curve (AUC) for the VR test (0.765) than for the MOCA test (0.598), and the sensitivity and specificity of the VR program were 0.833 and 0.722, respectively. Salivary DHEA was correlated with VR total (R ² = 0.082, p = 0.01) and attention scores (R ² = 0.086, p = 0.009).

CONCLUSION

The VR cognitive test was as effective as the traditional MOCA test in the MCI classification and safe enough for older adults to perform, indicating its potential as a diagnostic tool. It has also been shown that salivary DHEA can be used as a biomarker for MCI.

Study of virtual reality for mild cognitive impairment: A bibliometric analysis using CiteSpace

Objectives

Non-invasive and low-cost virtual reality (VR) technology is important for early evaluation and intervention in mild cognitive impairment (MCI). This study aimed to demonstrate the current status of overseas and domestic research as well as the focus and frontier of VR technology among individuals with MCI through a bibliometric analysis.

Methods

Studies from the core collection of Web of Science™ between 1995 and 2020 were used; furthermore, CiteSpace 5.7 R3 was utilized to analyse information on authors/cited authors, keywords, burst words, and cited references.

Results

In total, 230 publications were identified. Most studies were published in the USA (45 publications) and Italy (41 publications), where Guiseppe Riva ranks first (14 publications), and Tarnanas I is the author with the highest centrality (0.44). The hot topics in VR applications in the MCI population are ‘physical activity,’ ‘people,’ ‘single-blind,’ ‘disease,’ ‘walking,’ ‘technology,’ ‘working memory,’ and ‘risk’ in recent years. The keyword ‘mild cognitive impairment’ has attracted extensive attention since 2012, showing the strongest citation outbreak (8.28). The clustering results of the literature show the research types and emerging trends, including ‘exergame,’ ‘serious games,’ ‘spatial navigation,’ ‘activities of daily living,’ ‘exercise,’ ‘enriched environment’ and ‘wayfinding.‘

Conclusions

Cognitive assessment and nonpharmacological intervention research on patients with MCI have become the focus of dementia prevention in recent years. Virtual technology, combined with traditional methods such as exercise therapy, provides new ideas for innovative cognitive evaluation and cognitive intervention.

Dual-Task Gait as a Predictive Tool for Cognitive Impairment in Older Adults: A Systematic Review

The use of the dual-task model as a cognitive-motor interface has been extensively investigated in cross-sectional studies as a training task in cognitive impairment. However, few existing longitudinal studies prove the usefulness of this tool as a clinical marker of cognitive impairment in older people. What is the evidence in prospective studies about dual-task gait as a predictor of cognitive impairment in older adults? This study aims to review and discuss the current state of knowledge in prospective studies on the use of dual-task gait as a predictive tool for cognitive impairment in older adults. The methodology used was a systematic review, according to the PRISMA criteria for the search, summarize and report. A search in 3 databases (Pubmed, Web of Science, and Scopus) was carried out until April 2021. The search terms used were: "(gait OR walking) AND (cognitive decline) AND (dual-task) AND (follow-up OR longitudinal OR long-term OR prospective OR cohort OR predict)." We included prospective research articles with older people with cognitive evaluation at the beginning and the end of the follow-up and dual-task gait paradigm as initial evaluation associated with the presentation of cognitive impairment prediction using any dual-task gait parameters. After exclusion criteria, 12 studies were reviewed. The results indicate that eight studies consider dual-task gait parameters a useful cognitive-motor tool, finding that some of the evaluated parameters of dual-task gait significantly correlate with cognitive impairment over time. The most promising DT parameters associated with cognitive impairment prediction seem to be gait speed, speed cost, DT time, numbers of words during DT, among others. In sum, this study reviews the variety of dual-task gait parameters and their relevance as a simple tool for early cognitive impairment screening, opening a diagnostic window for the screening of cognitive impairment in older people.

Interindividual and intraindividual variability in amnestic mild cognitive impairment (aMCI) measured with an online cognitive assessment

INTRODUCTION

Mean cognitive performance is worse in amnestic mild cognitive impairment (aMCI) compared to control groups. However, studies on variability of cognitive performance in aMCI have yielded inconclusive results, with many differences in variability measures and samples from one study to another.

METHODS

We examined variability in aMCI using an existing older adult sample (n = 91; 51 with aMCI, 40 with normal cognition for age), measured with an online self-administered computerized cognitive assessment (Cogniciti's Brain Health Assessment). Our methodology extended past findings by using pure measures of variability (controlling for confounding effects of group performance or practice), and a clinically representative aMCI sample (reflecting the continuum of cognitive performance between normal cognition and aMCI).

RESULTS

Between-group t-tests showed significantly greater between-person variability (interindividual variability or diversity) in overall cognitive performance in aMCI than controls, although the effect size was with a small to moderate effect size, d = 0.44. No significant group differences were found in within-person variability (intraindividual variability) across cognitive tasks (dispersion) or across trials of a response time task (inconsistency), which may be because we used a sample measuring the continuum of cognitive performance. Exploratory correlation analyses showed that a worse overall score was associated with greater inter- and intraindividual variability, and that variability measures were correlated with each other, indicating people with worse cognitive performance were more variable.

DISCUSSION

The current study demonstrates that self-administered online tests can be used to remotely assess different types of variability in people at risk of Alzheimer`s. Our findings show small but significantly more interindividual differences in people with aMCI. This diversity is considered as "noise" in standard assessments of mean performance, but offers an interesting and cognitively informative "signal" in itself.

Physical Training In-Game Metrics for Cognitive Assessment: Evidence from Extended Trials with the Fitforall Exergaming Platform

Conventional clinical cognitive assessment has its limitations, as evidenced by the environmental shortcomings of various neuropsychological tests conducted away from an older person’s everyday environment. Recent research activities have focused on transferring screening tests to computerized forms, as well as on developing short screening tests for screening large populations for cognitive impairment. The purpose of this study was to present an exergaming platform, which was widely trialed (116 participants) to collect in-game metrics (built-in game performance measures). The potential correlation between in-game metrics and cognition was investigated in-depth by scrutinizing different in-game metrics. The predictive value of high-resolution monitoring games was assessed by correlating it with classical neuropsychological tests; the area under the curve (AUC) in the receiver operating characteristic (ROC) analysis was calculated to determine the sensitivity and specificity of the method for detecting mild cognitive impairment (MCI). Classification accuracy was calculated to be 73.53% when distinguishing between MCI and normal subjects, and 70.69% when subjects with mild dementia were also involved. The results revealed evidence that careful design of serious games, with respect to in-game metrics, could potentially contribute to the early and unobtrusive detection of cognitive decline.

Psychometric Properties of Cognitive-Motor Dual-Task Studies With the Aim of Developing a Test Protocol for Persons With Vestibular Disorders: A Systematic Review

OBJECTIVES

Patients suffering from vestibular disorders (VD) often present with impairments in cognitive domains such as visuospatial ability, memory, executive function, attention, and processing speed. These symptoms can be attributed to extensive vestibular projections throughout the cerebral cortex and subcortex on the one hand, and to increased cognitive-motor interference (CMI) on the other hand. CMI can be assessed by performing cognitive-motor dual-tasks (DTs). The existing literature on this topic is scarce and varies greatly when it comes to test protocol, type and degree of vestibular impairment, and outcome. To develop a reliable and sensitive test protocol for VD patients, an overview of the existing reliability and validity studies on DT paradigms will be given in a variety of populations, such as dementia, multiple sclerosis, Parkinson's disease, stroke, and elderly.

DESIGN

The systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An extensive literature search on psychometric properties of cognitive-motor DTs was run on MEDLINE, Embase, and Cochrane Databases. The studies were assessed for eligibility by two independent researchers, and their methodological quality was subsequently evaluated using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN).

RESULTS AND CONCLUSIONS

Thirty-three studies were included in the current review. Based on the reliability and validity calculations, including a static as well as dynamic motor task seems valuable in a DT protocol for VD patients. To evoke CMI maximally in this population, both motor tasks should be performed while challenging the vestibular cognitive domains. Out of the large amount of cognitive tasks employed in DT studies, a clear selection for each of these domains, except for visuospatial abilities, could be made based on this review. The use of the suggested DTs will give a more accurate and daily life representation of cognitive and motor deficiencies and their interaction in the VD population.

Deterioration, Compensation and Motor Control Processes in Healthy Aging, Mild Cognitive Impairment and Alzheimer's Disease

Aging is associated with modifications of several brain structures and functions. These modifications then manifest as modified behaviors. It has been proposed that some brain function modifications may compensate for some other deteriorated ones, thus maintaining behavioral performance. Through the concept of compensation versus deterioration, this article reviews the literature on motor function in healthy and pathological aging. We first highlight mechanistic studies that used paradigms, allowing us to identify precise compensation mechanisms in healthy aging. Subsequently, we review studies investigating motor function in two often-associated neurological conditions, i.e., mild cognitive impairment and Alzheimer's disease. We point out the need to expand the knowledge gained from descriptive studies with studies targeting specific motor control processes. Teasing apart deteriorated versus compensating processes represents precious knowledge that could significantly improve the prevention and rehabilitation of age-related loss of mobility.

Digital biomarker-based individualized prognosis for people at risk of dementia

Background

Research investigating treatments and interventions for cognitive decline fail due to difficulties in accurately recognizing behavioral signatures in the presymptomatic stages of the disease. For this validation study, we took our previously constructed digital biomarker‐based prognostic models and focused on generalizability and robustness of the models.

Method

We validated prognostic models characterizing subjects using digital biomarkers in a longitudinal, multi‐site, 40‐month prospective study collecting data in memory clinics, general practitioner offices, and home environments.

Results

Our models were able to accurately discriminate between healthy subjects and individuals at risk to progress to dementia within 3 years. The model was also able to differentiate between people with or without amyloid neuropathology and classify fast and slow cognitive decliners with a very good diagnostic performance.

Conclusion

Digital biomarker prognostic models can be a useful tool to assist large‐scale population screening for the early detection of cognitive impairment and patient monitoring over time.

Effectiveness of exergames for improving mobility and balance in older adults: a systematic review and meta-analysis

BACKGROUND

Exergaming is a fun, engaging, and interactive form of exercising that may help overcome some of the traditional exercise barriers and help improve adherence on the part of older adults, providing therapeutic applications for balance recovery and functional mobility. The purpose of this systematic review is to summarize the effects of exergames on mobility and balance in older adults.

METHODS

The PRISMA guidelines for systematic reviews were followed. The following databases were searched from inception to August 2019: Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, PEDro, CINAHL, and INSPEC. We selected randomized controlled trials that assessed the effects of exergames on balance or mobility of older adults without neurological conditions, in comparison to no intervention or health education. Two review authors independently screened the trials' titles and abstracts and identified trials for inclusion according to the eligibility criteria. An almost perfect agreement between the authors was observed with respect to interrater reliability of trial selection (kappa = 0.84; P < 0.001). We performed descriptive analysis of the quantitative data to summarize the evidence. Meta-analysis was carried out using RevMan. A random effects model was used to compute the pooled prevalence with 95% confidence intervals.

RESULTS

After screening 822 records, 12 trials comparing exergames with no intervention were included. A total of 1520 older adults participated in the studies, with a mean age of 76 ± 6 years for the experimental group and 76 ± 5 years for the control group. Quantitative synthesis showed significant improvements in balance and mobility based on the center of pressure sway (SMD = - 0.89; 95%CI = - 1.26 to - 0.51; P = 0.0001; I² = 58%), Berg Balance Scale (MD = 2.15; 95%CI = 1.77 to 2.56; P = 0.0001; I² = 96%), and on Timed Up and Go test (MD = - 2.48; 95%CI = - 3.83 to - 1.12; P = 0.0003; I² = 0).

CONCLUSIONS

Exergames improved balance and mobility in older adults without neurological disorders and motivate patients to keep performing balance exercises. High quality studies with standardized assessment protocols are necessary to improve the strength of the evidence.

Reflective and Reflexive Stress Responses of Older Adults to Three Gaming Experiences In Relation to Their Cognitive Abilities: Mixed Methods Crossover Study

BACKGROUND

The gamification of digital health provisions for older adults (eg, for rehabilitation) is a growing trend; however, many older adults are not familiar with digital games. This lack of experience could cause stress and thus impede participants' motivations to adopt these technologies.

OBJECTIVE

This crossover longitudinal multifactorial study aimed to examine the interactions between game difficulty, appraisal, cognitive ability, and physiological and cognitive responses that indicate game stress using the Affective Game Planning for Health Applications framework.

METHODS

A total of 18 volunteers (mean age 71 years, SD 4.5; 12 women) completed a three-session study to evaluate different genres of games in increasing order of difficulty (S₁-BrainGame, S₂-CarRace, and S₃-Exergame). Each session included an identical sequence of activities (t₁-Baseline, t₂-Picture encode, t₃-Play, t₄-Stroop test, t₅-Play, and t₆-Picture recall), a repeated sampling of salivary cortisol, and time-tagged ambulatory data from a wrist-worn device. Generalized estimating equations were used to investigate the effect of session×activity or session×activity×cognitive ability on physiology and cognitive performance. Scores derived from the Montreal Cognitive Assessment (MoCA) test were used to define cognitive ability (MoCA-high: MoCA>27, n=11/18). Kruskal-Wallis tests were used to test session or session×group effects on the scores of the postgame appraisal questionnaire.

RESULTS

Session×activity effects were significant on all ambulatory measures (χ²₁₀>20; P<.001) other than cortisol (P=.37). Compared with S₁ and S₂, S₃ was associated with approximately 10 bpm higher heart rate (P<.001) and approximately 5 muS higher electrodermal activity (P<.001), which were both independent of the movement caused by the exergame. Compared with S₁, we measured a moderate but statistically significant drop in the rate of hits in immediate recall and rate of delayed recall in S₃. The low-MoCA group did not differ from the high-MoCA group in general characteristics (age, general self-efficacy, and perceived stress) but was more likely to agree with statements such as digital games are too hard to learn. In addition, the low-MoCA group was more likely to dislike the gaming experience and find it useless, uninteresting, and visually more intense (χ²₁>4; P<.04). Group differences in ambulatory signals did not reach statistical significance; however, the rate of cortisol decline with respect to the baseline was significantly larger in the low-MoCA group.

CONCLUSIONS

Our results show that the experience of playing digital games was not stressful for our participants. Comparatively, the neurophysiological effects of exergame were more pronounced in the low-MoCA group, suggesting greater potential of this genre of games for cognitive and physical stimulation by gamified interventions; however, the need for enjoyment of this type of challenging game must be addressed.

Detection of Mild Cognitive Impairment Based on Virtual Reality: A Scoping Review

BACKGROUND

To delay the decline in cognition and reduce the incidence of dementia, the precise detection of Mild Cognitive Impairment (MCI) is necessary. The application of Virtual Reality (VR) technology in this detection can overcome the shortage of traditional paper-and-pencil tests.

OBJECTIVE

This review aimed to summarize the research progress of the detection of MCI using VR.

METHODS

Eight databases from their inception to November 19, 2019, were systematically searched for studies applying VR in the detection of MCI. A thematic analysis was conducted according to the specific detection purpose and the main corresponding cognitive domains assessed were summarized; characteristics of the VR applications were also summarized.

RESULTS

Twenty-eight studies were finally included. The detection purposes included discrimination between healthy controls and those with MCI, discrimination between aMCI subtypes, detection of MCI patients at risk of Alzheimer's Disease (AD), and discrimination between MCI and AD. VR tasks assessing spatial memory were applicable for all detection purposes, and the assessment of combinations of memory and executive function seemed more sensitive. Executive function and intentional episodic memory could be assessed to discriminate among healthy controls, individuals with MCI and those with AD. Incidental episodic memory was effective in detecting MCI with hippocampal atrophy. The most common characteristics of the VR applications were the use of semi-immersion, joysticks or gamepad interactions and simple, one-time behavioral assessments.

CONCLUSION

VR applications are promising in the detection of MCI, but further research is needed for clinical use.

Use of nonintrusive sensor-based information and communication technology for real-world evidence for clinical trials in dementia

Cognitive function is an important end point of treatments in dementia clinical trials. Measuring cognitive function by standardized tests, however, is biased toward highly constrained environments (such as hospitals) in selected samples. Patient-powered real-world evidence using information and communication technology devices, including environmental and wearable sensors, may help to overcome these limitations. This position paper describes current and novel information and communication technology devices and algorithms to monitor behavior and function in people with prodromal and manifest stages of dementia continuously, and discusses clinical, technological, ethical, regulatory, and user-centered requirements for collecting real-world evidence in future randomized controlled trials. Challenges of data safety, quality, and privacy and regulatory requirements need to be addressed by future smart sensor technologies. When these requirements are satisfied, these technologies will provide access to truly user relevant outcomes and broader cohorts of participants than currently sampled in clinical trials.

Smart Aging Platform for Evaluating Cognitive Functions in Aging: A Comparison with the MoCA in a Normal Population

Background: Smart Aging is a Serious games (SGs) platform in a 3D virtual environment in which users perform a set of screening tests that address various cognitive skills. The tests are structured as 5 tasks of activities of daily life in a familiar environment. The main goal of the present study is to compare a cognitive evaluation made with Smart Aging with those of a classic standardized screening test, the Montreal Cognitive Assessment (MoCA).

Methods: One thousand one-hundred thirty-one healthy adults aged between 50 and 80 (M = 64.3 ± 8.3) were enrolled in the study. They received a cognitive evaluation with the MoCA and the Smart Aging platform. Participants were grouped according to their MoCA global and specific cognitive domain (i.e., memory, executive functions, working memory, visual spatial elaboration, language, and orientation) scores and we explored differences among these groups in the Smart Aging indices.

Results: One thousand eighty-six older adults (M = 64.0 ± 8.0) successfully completed the study and were stratified according to their MoCA score: Group 1 with MoCA < 27 (n = 360); Group 2 with 27 ≥ MoCA < 29 (n = 453); and Group 3 with MoCA ≥ 29 (n = 273). MoCA groups significantly differed in most of the Smart Aging indices considered, in particular as concerns accuracy (ps < 0.001) and time (ps < 0.001) for completing most of the platform tasks. Group 1 was outperformed by the other two Groups and was slower than them in these tasks, which were those supposed to assess memory and executive functions. In addition, significant differences across groups also emerged when considering the single cognitive domains of the MoCA and the corresponding performances in each Smart Aging task. In particular, this platform seems to be a good proxy for assessing memory, executive functions, working memory, and visual spatial processes.

Conclusion: These findings demonstrate the validity of Smart Aging for assessing cognitive functions in normal aging. Future studies will validate this platform also in the clinical aging populations.

Loss of gait control assessed by cognitive-motor dual-tasks: pros and cons in detecting people at risk of developing Alzheimer's and Parkinson's diseases

Alzheimer's and Parkinson's diseases are age-related progressive neurodegenerative diseases of increasing prevalence worldwide. In the absence of curative therapy, current research is interested in prevention, by identifying subtle signs of early-stage neurodegeneration. Today, the field of behavioral neuroscience has emerged as one of the most promising areas of research on this topic. Recently, it has been shown that the exacerbation of gait disorders under dual-task conditions (i.e., simultaneous performance of cognitive and motor tasks) could be a characteristic feature of Alzheimer's and Parkinson's diseases. The cognitive-motor dual-task paradigm during walking allows to assess whether (i) executive attention is abnormally impaired in prodromal Alzheimer's disease or (ii) compensation strategies are used in order to preserve gait function when the basal ganglia system is altered in prodromal Parkinson's disease. This review aims at (i) identifying patterns of dual-task-related gait changes that are specific to Alzheimer's and Parkinson's diseases, respectively, (ii) demonstrating that these changes could potentially be used as prediagnostic markers for disease onset, (iii) reviewing pros and cons of existing dual-task studies, and (iv) proposing future directions for clinical research.

What can gait tell us about dementia? Review of epidemiological and neuropsychological evidence

BACKGROUND

Cognitive impairment and gait disorders in people over the age of 65 represent major public health issues because of their high frequency, their link to poor outcomes and high costs. Research has demonstrated that these two geriatric syndromes are closely related.

METHODS AND RESULTS

We aim to review the evidence supporting the relationship between gait and cognitive impairment, particularly focusing on epidemiological and neuropsychological studies in patients with Mild cognitive impairment, Alzheimer's disease and Vascular dementia. The review demonstrates that gait and cognition are closely related, but our knowledge of their interrelationship is limited. Emerging evidence shows that gait analysis has the potential to contribute to diagnosis and prognosis of cognitive impairment.

CONCLUSIONS

An integrated approach for evaluating these major geriatric syndromes, based on their close relationship, will not only increase our understanding of cognitive-motor interactions, but most importantly may be used to aid early diagnosis, prognosis and the development of new interventions.

Trends on the application of serious games to neuropsychological evaluation: A scoping review

BACKGROUND

The dramatic technological advances witnessed in recent years have resulted in a great opportunity for changing the way neuropsychological evaluations may be performed in clinical practice. Particularly, serious games have been posed as the cornerstone of this still incipient paradigm-shift, as they have characteristics that make them especially advantageous in trying to overcome limitations associated with traditional pen-and-paper based neuropsychological tests: they can be easily administered and they can feature complex environments for the evaluation of neuropsychological constructs that are difficult to evaluate through traditional tests. The objective of this study was to conduct a scoping literature review in order to map rapidly the key concepts underpinning this research area during the last 25years on the use of serious games for neuropsychological evaluation.

METHODS

MEDLINE, PsycINFO, Scopus and IEEE Xplore databases were systematically searched. The main eligibility criteria were to select studies published in a peer-reviewed journal; written in English; published in the last 25years; focused on the human population, and classified in the neuropsychological field. Moreover, to avoid risk of bias, studies were selected by consensus of experts, focusing primarily in psychometric properties. Therefore, selected studies were analyzed in accordance with a set of dimensions of analysis commonly used for evaluating neuropsychological tests.

RESULTS

After applying the selected search strategy, 57 studies -including 54 serious games- met our selection criteria. The selected studies deal with visuospatial capabilities, memory, attention, executive functions, and complex neuropsychological constructs such as Mild Cognitive Impairment (MCI). Results show that the implementation of serious games for neuropsychological evaluation is tackled in several different ways in the selected studies, and that studies have so far been mainly exploratory, just aiming at testing the feasibility of the proposed approaches.

DISCUSSION

It may be argued that the limited number of databases used might compromise this study. However, we think that the finally included sample is representative, in spite of how difficult is to achieve an optimum and maximum scope. Indeed, this review identifies other research issues related to the development of serious games beyond their reliability and validity. The main conclusion of this review is that there is a great interest in the research community in the use of serious games for neuropsychological evaluation. This scoping review is pertinent, in accordance with the increasing number of studies published in the last three years, they demonstrate its potential as a serious alternative to classic neuropsychological tests. Nevertheless, more research is needed in order to implement serious games that are reliable, valid, and ready to be used in the everyday clinical practice.

Mnemonic strategy training of the elderly at risk for dementia enhances integration of information processing via cross-frequency coupling

Introduction

We sought to identify whether intensive 10-week mobile health mnemonic strategy training (MST) could shift the resting-state brain network more toward cortical-level integration, which has recently been proven to reflect the reorganization of the brain networks compensating the cognitive decline.

Methods

One hundred fifty-eight patients with mild cognitive impairment (MCI) were selected and participated in 10-week training lasting 90 min/d of memory training. They benefited from an initial and a follow-up neuropsychological evaluation and resting-state electroencephalography (EEG).

Results

At follow-up, MST revealed an extensive significant training effect that changed the network with an increase of synchronization between parietotemporal and frontal areas; frontal^θ-parietal^α2 causal strengthening as part of top-down inhibitory control; enhancement of sensorimotor connections in β band; and a general increase of cortical-level integration. More precisely, MST induced gain as an increase of the global cost efficiency (GCE) of the whole cortical network and a neuropsychological performance improvement, which was correlated with it (r = 0.32, P = .0001). The present study unfolded intervention changes based on EEG source activity via novel neuroinformatic tools for revealing intrinsic coupling modes in both amplitude-phase representations and in the mixed spectrospatiotemporal domain.

Discussion

Further work should identify whether the GCE enhancement of the functional cortical brain networks is a compensation mechanism to the brain network dysfunction or a more permanent neuroplasticity effect.

The Impact of Mild Cognitive Impairment on Gait and Balance: A Systematic Review and Meta-Analysis of Studies Using Instrumented Assessment

BACKGROUND

In addition to cognitive deficits, people with mild cognitive impairment (MCI) can experience motor dysfunction, including deficits in gait and balance. Objective, instrumented motor performance assessment may allow the detection of subtle MCI-related motor deficits, allowing early diagnosis and intervention. Motor assessment under dual-task conditions may increase diagnostic accuracy; however, the sensitivity of different cognitive tasks is unclear.

OBJECTIVE

To systematically review the extant literature focusing on instrumented assessment of gait and balance parameters for discriminating MCI patients from cognitively intact peers.

METHODS

Database searches were conducted in PubMed, EMBASE, Cochrane Library, PsycINFO and Web of Science. Inclusion criteria were: (1) clinically confirmed MCI; (2) instrumented measurement of gait and/or balance; (3) English language, and (4) reporting gait or balance parameters which could be included in a meta-analysis for discriminating between MCI patients and cognitively intact individuals based on weighted effect size (d).

RESULTS

Fourteen studies met the inclusion criteria and reported quantitative gait (n = 11) or postural balance (n = 4) parameters to be included in the meta-analysis. The meta-analysis revealed that several gait parameters including velocity (d = -0.74, p < 0.01), stride length (d = -0.65, p < 0.01), and stride time (mean: d = 0.56, p = 0.02; coefficient of variation: d = 0.50, p < 0.01) discriminated best between MCI and healthy controls under single-task conditions. Importantly, dual-task assessment increased the discriminative power of gait variables wherein gait variables with counting tasks appeared to be more sensitive (range d = 0.84-1.35) compared to verbal fluency tasks such as animal naming (range d = 0.65-0.94). Balance parameters identified as significant discriminators were anterior-posterior (d = 0.49, p < 0.01) and mediolateral (d = -0.34, p = 0.04) sway position in the eyes-open condition but not eyes-closed condition.

CONCLUSION

Existing studies provide evidence that MCI affects specific gait parameters. MCI-related gait changes were most pronounced when subjects are challenged cognitively (i.e., dual task), suggesting that gait assessment with an additional cognitive task is useful for diagnosis and outcome analysis in the target population. Static balance seems to also be affected by MCI, although limited evidence exists. Instrumented motor assessment could provide a critical opportunity for MCI diagnosis and tailored intervention targeting specific deficits and potentially slowing progression to dementia. Further studies are required to confirm our findings.

Five-year biomarker progression variability for Alzheimer's disease dementia prediction: Can a complex instrumental activities of daily living marker fill in the gaps?

Introduction

Biomarker progressions explain higher variability in cognitive decline than baseline values alone. This study examines progressions of established biomarkers along with a novel marker in a longitudinal cognitive decline.

Methods

A total of 215 subjects were used with a diagnosis of normal, mild cognitive impairment (MCI) or Alzheimer's disease (AD) at baseline. We calculated standardized biomarker progression rates and used them as predictors of outcome within 5 years.

Results

Early cognitive declines were more strongly explained by fluorodeoxyglucose-positron emission tomography, precuneus and medial temporal cortical thickness, and the complex instrumental activities of daily living (iADL) marker progressions. Using Cox proportional hazards model, we found that these progressions were a significant risk factor for conversion from both MCI to AD (adjusted hazard ratio 1.45; 95% confidence interval 1.20–1.93; P = 1.23 × 10⁻⁵) and cognitively normal to MCI (adjusted hazard ratio 1.76; 95% confidence interval 1.32–2.34; P = 1.55 × 10⁻⁵).

Discussion

Compared with standard biological biomarkers, complex functional iADL markers could also provide predictive information for cognitive decline during the presymptomatic stage. This has important implications for clinical trials focusing on prevention in asymptomatic individuals.

A novel biomarker of amnestic MCI based on dynamic cross-frequency coupling patterns during cognitive brain responses

The detection of mild cognitive impairment (MCI), the transitional stage between normal cognitive changes of aging and the cognitive decline caused by AD, is of paramount clinical importance, since MCI patients are at increased risk of progressing into AD. Electroencephalographic (EEG) alterations in the spectral content of brainwaves and connectivity at resting state have been associated with early-stage AD. Recently, cognitive event-related potentials (ERPs) have entered into the picture as an easy to perform screening test. Motivated by the recent findings about the role of cross-frequency coupling (CFC) in cognition, we introduce a relevant methodological approach for detecting MCI based on cognitive responses from a standard auditory oddball paradigm. By using the single trial signals recorded at Pz sensor and comparing the responses to target and non-target stimuli, we first demonstrate that increased CFC is associated with the cognitive task. Then, considering the dynamic character of CFC, we identify instances during which the coupling between particular pairs of brainwave frequencies carries sufficient information for discriminating between normal subjects and patients with MCI. In this way, we form a multiparametric signature of impaired cognition. The new composite biomarker was tested using data from a cohort that consists of 25 amnestic MCI patients and 15 age-matched controls. Standard machine-learning algorithms were employed so as to implement the binary classification task. Based on leave-one-out cross-validation, the measured classification rate was found reaching very high levels (95%). Our approach compares favorably with the traditional alternative of using the morphology of averaged ERP response to make the diagnosis and the usage of features from spectro-temporal analysis of single-trial responses. This further indicates that task-related CFC measurements can provide invaluable analytics in AD diagnosis and prognosis.