Attention and memory in the preclinical stage of dementia

Cognitive impairment assessment through handwriting (COGITAT) score: a novel tool that predicts cognitive state from handwriting for forensic and clinical applications

Introduction

Handwriting deteriorates proportionally to the writer's cognitive state. Such knowledge is of special importance in the case of a contested will, where dementia of the testator is claimed, but medical records are often insufficient to decide what the testator's cognitive state really was. By contrast, if the will is handwritten, handwriting analysis allows us to gauge the testator's cognitive state at the precise moment when he/she was writing the will. However, quantitative methods are needed to precisely evaluate whether the writer's cognitive state was normal or not. We aim to provide a test that quantifies handwriting deterioration to gauge a writer's cognitive state.

Methods

We consecutively enrolled patients who came for the evaluation of cognitive impairment at the Outpatient Clinic for Cognitive Impairment of the Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Sciences (DINOGMI) of the University of Genoa, Italy. Additionally, we enrolled their caregivers. We asked them to write a short text by hand, and we administered the Mini Mental State Examination (MMSE). Then, we investigated which handwriting parameters correlated with cognitive state as gauged by the MMSE.

Results

Our study found that a single score, which we called the COGnitive Impairment Through hAndwriTing (COGITAT) score, reliably allows us to predict the writer's cognitive state.

Conclusion

The COGITAT score may be a valuable tool to gage the cognitive state of the author of a manuscript. This score may be especially useful in contested handwritten wills, where clinical examination of the writer is precluded.

The assessment of executive function abilities in healthy and neurodegenerative aging-A selective literature review

Numerous studies have examined executive function (EF) abilities in cognitively healthy older adults and those living with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Currently, there are no standard accepted protocols for testing specific EFs; thus, researchers have used their preferred tool, which leads to variability in assessments of decline in a particular ability across studies. Therefore, there is a need for guidance as to the most sensitive tests for assessing EF decline. A search of the most current literature published between 2000 and 2022 on EF studies assessing cognitively healthy older adults and individuals living with MCI and AD was conducted using PubMed/Medline, PsycINFO, Embase, Web of Science, and Google Scholar. Emphasis was placed on the EF's dual-tasking, inhibition, shifting or switching, and working memory updating. Many tasks and their outcomes were reviewed. Of particular importance was the difference in outcomes for tasks applied to the same group of participants. These various EF assessment tools demonstrate differences in effectively identifying decline in EF ability due to the aging process and neurodegenerative conditions, such as MCI and AD. This review identifies various factors to consider in using particular EF tasks in particular populations, including task demand and stimuli factors, and also when comparing differing results across studies.

Working Memory Precision and Associative Binding in Mild Cognitive Impairment

To better understand working memory (WM) deficits in Mild Cognitive Impairment (MCI), we examined information precision and associative binding in WM in 21 participants with MCI, compared to 16 healthy controls, using an item-location delayed reproduction task. WM, along with other executive functions (i.e. Trail Making Task (TMT) and Stroop task), were measured before and after a 2-h nap. The napping manipulation was intended as an exploratory element to this study exploring potential impacts of napping on executive functions.Compared to healthy participants, participants with MCI exhibited inferior performance not only in identifying encoded WM items but also on item-location associative binding and location precision even when only one item was involved. We also found changes on TMT and Stroop tasks in MCI, reflecting inferior attention and inhibitory control. Post-napping performance improved in most of these WM and other executive measures, both in MCI and their healthy peers.Our study shows that associative binding and WM precision can reliably differentiate MCIs from their healthy peers. Additionally, most measures showed no differential effect of group pre- and post-napping. These findings may contribute to better understanding cognitive deficits in MCI therefore improving the diagnosis of MCI.

Effects of age on the interactions of attentional and emotional processes: a prefrontal fNIRS study

The aging of attentional and emotional functions has been extensively studied but relatively independently. Therefore, the relationships between aging and the interactions of attentional and emotional processes remain elusive. This study aimed to determine how age affected the interactions between attentional and emotional processes during adulthood. One-hundred forty adults aged 18-79 performed the emotional variant of the Attention Network Test, which probed alerting, orienting, and executive control in the presence and absence of threatening faces. During this task, contexts with varying levels of task preparatory processes were created to modulate the effect of threatening faces on attention, and functional near-infrared spectroscopy (fNIRS) was used to examine the neural underpinnings of the behavioural effects. The behavioural results showed that aging was associated with a significant decline in alerting efficiency, and there was a statistical trend for age-related deficits in executive control. Despite these age differences, age did not significantly moderate the interactions among attentional networks or between attention and emotion. Additionally, the fNIRS results showed that decreased frontal cortex functioning might underlie the age-related decline in executive control. Therefore, while aging has varying effects on different attentional networks, the interactions of attentional and emotional processes remain relatively unaffected by age.

The Relation Between Attention and Memory

The relation between attention and memory has long been deemed important for understanding cognition, and it was heavily researched even in the first experimental psychology laboratory by Wilhelm Wundt and his colleagues. Since then, the importance of the relation between attention and memory has been explored in myriad subdisciplines of psychology, and we incorporate a wide range of these diverse fields. Here, we examine some of the practical consequences of this relation and summarize work with various methodologies relating attention to memory in the fields of working memory, long-term memory, individual differences, life-span development, typical brain function, and neuropsychological conditions. We point out strengths and unanswered questions for our own embedded processes view of information processing, which is used to organize a large body of evidence. Last, we briefly consider the relation of the evidence to a range of other theoretical views before drawing conclusions about the state of the field.

Education, neighborhood environment, and cognitive decline: Findings from two prospective cohort studies of older adults in China

INTRODUCTION

The impacts of education on cognitive decline across different neighborhood environments (NEs) have rarely been studied.

METHODS

We investigated and compared the associations between educational attainment and cognitive decline using data of 1286 participants from the Taizhou Imaging Study (TIS) and the Shanghai Aging Study (SAS).

RESULTS

Compared with low-educated participants, in TIS with disadvantaged NE, high-educated participants manifested a significantly slower decline in global cognition (.062 Z score per year, P < .001), memory (.054 Z score per year, P < .05), and attention (.065 Z score per year, P < .01), whereas in SAS with advanced NE, highly educated individuals exhibited a slower decline only in attention (.028 Z score per year, P < .05).

DISCUSSION

We observed the additive effect of educational attainment and NE on cognitive decline in older adults. Education is especially important for maintaining cognitive health in a disadvantaged environment.

Attentional Control in Subjective Cognitive Decline

BACKGROUND

Attention is an essential cognitive ability that is necessary in other cognitive processes. Only few studies have focused on decline in specific functions of attention in older adults with cognitive decline. No research explores the difference in the proactive and reactive mode of control between the healthy control (HC) and older adults with subjective cognitive decline (SCD).

OBJECTIVE

The current work investigated whether there was any decline in alerting, orienting, and executive control in SCD. Particularly, the present study further explored the impairment of the proactive and reactive control in SCD.

METHODS

We recruited 25 HC and 26 SCD. All participants first finished a set of neuropsychological assessments. They then completed an Attention Network Test for measuring the alerting, orienting, and executive control, the List-wide and the Item-specific Proportion Congruency Effect task for measuring the proactive and reactive mode of control, respectively.

RESULTS

No difference was found in alerting, orienting, and executive control measured by the ANT between SCD and HC. The results also indicated no difference in the reactive control between SCD and HC. However, older adults with SCD performed worse in the proactive control as compared to HC.

CONCLUSION

Older adults with SCD showed an impairment in the proactive control. The current findings help us better understand objective decline in cognitive domains other than memory and shed light on early assessment and prevention of AD.

The reduced left hippocampal volume related to the delayed P300 latency in amnestic mild cognitive impairment

BACKGROUND

Amnestic mild cognitive impairment (aMCI) is characterized by delayed P300 latency and reduced grey matter (GM) volume, respectively. The relationship between the features in aMCI is unclear. This study was to investigate the relationship between the altered P300 latency and the GM volume in aMCI.

METHODS

Thirty-four aMCI and 34 well-matched normal controls (NC) were studied using electroencephalogram during a visual oddball task and scanned with MRI. Both tests were finished in the same day.

RESULTS

As compared with the NC group, the aMCI group exhibited delayed P300 latency in parietal cortex and reduced GM volumes in bilateral temporal pole and left hippocampus/parahippocampal gyrus. A remarkable negative correlation was found between delayed P300 latency and reduced left hippocampal volume only in the aMCI group. Interestingly, the mediating analysis found P300 latency significantly mediated the association between right supramarginal gyrus volume and information processing speed indicated by Stroop Color and Word Test A scores.

CONCLUSIONS

The association between delayed P300 latency and reduced left hippocampal volume in aMCI subjects suggests that reduced left hippocampal volume may be the potential structural basis of delayed P300 latency.

Serum alkaline phosphatase is elevated and inversely correlated with cognitive functions in subjective cognitive decline: results from the ReGAl 2.0 project

BACKGROUND

Alkaline phosphatase has been found on neuronal membranes and plasma alkaline phosphatase (ALP) activity increases during brain injury and cerebrovascular diseases, suggesting that its levels may reflect the neuronal loss. It is known that ALP is higher in subjects affected by Alzheimer's dementia and inversely correlated with cognitive functions. No study has investigated the relationship between ALP and cognitive functions in old-age subject with pre-clinical cognitive impairment.

METHODS

This is a cross-sectional study with data gathered from the ReGAl 2.0 project (Rete Geriatrica Alzheimer-Geriatric Network on Alzheimer's disease), a large Italian multicentric clinical-based study. A cohort of 209 old-age subjects healthy controls (HC), Subjective cognitive decline (SCD), and Mild Cognitive Impairment (MCI) was included in the study. Cognitive performances were assessed with a large neuropsychological battery. The same day, serum alkaline phosphatase activity was measured in all subjects.

RESULTS

We found that the SCD group had significantly higher ALP levels as compared with HC (p = 0.001). Among all neuropsychological tests, in all population ALP levels negatively correlated with scores at attentional matrices (r =  - 0.243, p = 0.002), Digit Span Forward (r =  - 0.241, p = 0.003) and Letter Fluency Test (r =  - 0.196, p = 0.044). Attentional Matrices (r =  - 0.208, p = 0.014) and Letter Fluency Test (r =  - 0.229, p = 0.019) remained significantly correlated with ALP even after controlling for gender. In the SCD group, only the Attentional Matrices significantly and negatively correlated with ALP (r =  - 0.344 p = 0.035), while no significant correlations were found in HC or MCI.

CONCLUSIONS

Results indicate that serum alkaline phosphatase activity is increased in SCD and inversely correlates with cognitive functions. Further studies are needed to investigate the role of ALP in the progression to AD.

Predicting the outcome of non-pharmacological treatment for patients with dementia-related mild cognitive impairment

Dementia is a progressive cognitive syndrome, with few effective pharmacological treatments that can slow its progress. Hence, non-pharmacological treatments (NPTs) play an important role in improving patient symptoms and quality of life. Designing the optimal personalised NPT strategy relies on objectively and quantitatively predicting the treatment outcome. Magnetoencephalography (MEG) findings can reflect the cognitive status of patients with dementia, and thus potentially predict NPT outcome. In the present study, 16 participants with cognitive impairment underwent NPT for several months. Their cognitive performance was evaluated based on the Mini-Mental State Examination and the Alzheimer's Disease Assessment Scale - Cognitive at the beginning and end of the NPT period, while resting-state brain activity was evaluated using MEG during the NPT period. Our results showed that the spectral properties of MEG signals predicted the changes in cognitive performance scores. High frequency oscillatory intensity at the right superior frontal gyrus medial segment, opercular part of the inferior frontal gyrus, triangular part of the inferior frontal gyrus, post central gyrus, and angular gyrus predicted the changes in cognitive performance scores. Thus, resting-state brain activity may be a powerful tool in designing personalised NPT.

Effect of Chlorogenic Acids on Cognitive Function in Mild Cognitive Impairment: A Randomized Controlled Crossover Trial

BACKGROUND

Mild cognitive impairment (MCI) is a global-scale issue, due in large part to the rapidly growing elderly population. The main polyphenol contained in coffee beans, chlorogenic acid (CGA), improves attention in healthy individuals. The utility of CGAs for treating MCI, however, has not been evaluated.

OBJECTIVE

To determine the effects of continuous CGA intake on cognitive function, especially attention, in patients diagnosed with MCI.

METHODS

The study was a randomized controlled crossover trial including 34 patients with MCI. Participants were randomly divided into two groups: Those who first ingested a placebo beverage and those who first ingested an active beverage containing CGAs (553.6 mg/bottle) twice daily for 12 weeks. After a 4-week washout period, the subjects ingested the other beverage (i.e., placebo or active beverage) in the same manner. Endpoint measures included scores on the Japanese version of the Mini-Mental State Examination (MMSE), the Japanese version of the Alzheimer's Disease Assessment Scale-cognitive component (ADAS-cog) testing overall cognitive function, and the Japanese version of the Trail Making Test (TMT-A, TMT-B) testing attention, along with the results of blood tests to evaluate safety.

RESULTS

In the TMT-B test, participants had a significantly reduced number of errors while ingesting the CGA beverage as compared with the placebo beverage (p < 0.05), although there was no difference in test completion time. Scores in the MMSE, ADAS-cog, and TMT-A did not differ significantly between conditions.

CONCLUSION

Continuous intake of CGAs appears to improve attention and executive function among cognitive functions in MCI.

Evaluation of the feasibility of an error-minimized approach to powered wheelchair skills training using shared control

BACKGROUND

Powered wheelchairs promote participation for people with mobility limitations. For older adults with cognitive impairment, existing training methods may not address learning needs, leading to difficulty with powered wheelchair skills. Error-minimized training, facilitated by shared control technology, may provide learning opportunities more suited to this population.

OBJECTIVE

The objective of this study was to evaluate the feasibility of an error-minimized approach to powered wheelchair skills training using shared control in residential care. Feasibility indicators were hypothesized a priori to be feasible for use in a definitive RCT.

METHODS

A 2 × 2 factorial RCT compared an error-minimized powered wheelchair skills training program (Co-pilot) to a control intervention at two doses (6 sessions vs. 12 sessions). Data were collected on the feasibility of study processes (e.g., recruitment), resources (e.g., participant time), management (e.g., technology reliability), and training outcomes (e.g., adverse events, clinical outcomes).

RESULTS

Twenty-five older adults with cognitive impairment participated in the study. Technical issues were encountered in 14.5% of training sessions. Participants receiving 6 sessions of training adhered better to the treatment than those receiving 12 sessions. All participants learned the skills required for PWC use with minor errors, regardless of the training method or dose. Co-pilot participants and trainers reported feelings of safety and training benefits with the use of shared control technology.

CONCLUSIONS

Individuals with mild to moderate cognitive impairment are able to learn the skills required to drive a powered wheelchair in as few as six training sessions. Further evaluation of the Co-pilot training program is required.IMPLICATIONS FOR REHABILITATIONShared control teleoperation technology may be used to augment learning in older adults with cognitive impairments.Evaluation of the feasibility of use of novel rehabilitation technologies is critical prior to engaging in large-scale clinical research.Individuals with cognitive impairment are able to learn the required skills for operation of a powered wheelchair.

Effectiveness of sorting tests for detecting cognitive decline in older adults with dementia and other common neurodegenerative disorders: A meta-analysis

The demand for simple, accurate and time-efficient screens to detect cognitive decline at point-of-care is increasing. Sorting tests are often used to detect the 'executive' deficits that are commonly associated with behavioural-variant frontotemporal dementia (bvFTD), but their potential for use as a cognitive screen with older adults is unclear. A comprehensive search of four databases identified 142 studies that compared the sorting test performance (e.g. WCST, DKEFS-ST) of adults with a common neurodegenerative disorder (e.g. Alzheimer's disease, vascular dementia, bvFTD, Parkinson's disease) and cognitively-healthy controls. Hedges' g effect sizes were used to compare the groups on five common test scores (Category, Total, Perseveration, Error, Description). The neurodegenerative disorders (combined) showed large deficits on all scores (g -1.0 to -1.3), with dementia (combined subtypes) performing more poorly (g -1.2 to -2.1), although bvFTD was not disproportionately worse than the other dementias. Overall, sorting tests detected the cognitive impairments caused by common neurodegenerative disorders, especially dementia, highlighting their potential suitability as a cognitive screen for older adults.

Effect of Spatial Disorientation in a Virtual Environment on Gait and Vital Features in Patients with Dementia: Pilot Single-Blind Randomized Control Trial

Background

Orientation deficits are among the most devastating consequences of early dementia. Digital navigation devices could overcome these deficits if adaptable to the user’s needs (ie, provide situation-aware, proactive navigation assistance). To fulfill this task, systems need to automatically detect spatial disorientation from sensors in real time. Ideally, this would require field studies consisting of real-world navigation. However, such field studies can be challenging and are not guaranteed to cover sufficient instances of disorientation due to the large variability of real-world settings and a lack of control over the environment.

Objective

Extending a foregoing field study, we aim to evaluate the feasibility of using a sophisticated virtual reality (VR) setup, which allows a more controlled observation of disorientation states and accompanying behavioral and physiological parameters in cognitively healthy older people and people with dementia.

Methods

In this feasibility study, we described the experimental design and pilot outcomes of an ongoing study aimed at investigating the effect of disorientation on gait and selected physiological features in a virtual laboratory. We transferred a real-world navigation task to a treadmill-based virtual system for gait analysis. Disorientation was induced by deliberately manipulating landmarks in the VR projection. Associated responses in motion behavior and physiological parameters were recorded by sensors. Primary outcomes were variations in motion and physiological parameters, frequency of disorientation, and questionnaire-derived usability estimates (immersion and perceived control of the gait system) for our population of interest. At this time, the included participants were 9 cognitively healthy older participants [5/9 women, 4/9 men; mean age 70 years, SD 4.40; Mini–Mental State Examination (MMSE) mean 29, SD 0.70) and 4 participants with dementia (2/4 women, 2/4 men; mean age 78 years, SD 2.30 years; MMSE mean 20.50, SD 7.54). Recruitment is ongoing, with the aim of including 30 cognitively healthy older participants and 20 participants with dementia.

Results

All 13 participants completed the experiment. Patients’ route was adapted by shortening it relative to the original route. Average instances of disorientation were 21.40, 36.50, and 37.50 for the cognitively healthy older control, cognitively healthy older experimental participants, and participants with dementia, respectively. Questionnaire outcomes indicated that participants experienced adequate usability and immersion; 4.30 for presence, 3.73 for involvement, and 3.85 for realism of 7 possible points, indicating a good overall ability to cope with the experiment. Variations were also observed in motion and physiological parameters during instances of disorientation.

Conclusions

This study presents the first feasibility outcomes of a study investigating the viability of using a sophisticated VR setup, based on an earlier real-world navigation study, to study spatial disorientation among cognitively healthy older people and people with dementia. Preliminary outcomes give confidence to the notion that our setup can be used to assess motion and physiological markers of disorientation, even in people with cognitive decline.

Trial Registration

ClinicalTrials.gov; https://clinicaltrials.gov/ct2/show/NCT04134806

Attention and Functional Connectivity Among Patients With Early-Stage Subcortical Ischemic Vascular Disease and Alzheimer's Disease

The current study compared attention profiles and functional connectivity of frontal regions in patients with early-stage subcortical ischemic vascular disease (SIVD) and Alzheimer's disease (AD). Twenty patients with SIVD, 32 patients with AD, and 23 subjects with normal cognition (NC) received cognition and resting-state functional MRI (rs-fMRI) evaluations. The Cognitive Abilities Screening Instrument (CASI) was used to assess global cognition, and simple attention, processing speed, divided attention, and vigilance/sustained attention were evaluated using the Digit Span Forward, Trail Making Test, Symbol Digit Modality Test, and Conners Continuous Performance Test, respectively. Voxel-based regional homogeneity (ReHo) derived from rs-fMRI data was analyzed to identify significant clusters, which were further correlated with attention profiles. Although the patients with SIVD and AD had comparable global cognitive ability, those with SIVD exhibited worse divided attention and vigilance/sustained attention than those with AD. Compared with the NC group, the patients with SIVD exhibited decreased ReHo within the right middle frontal gyrus (MFG) and left anterior cingulate gyrus (ACG), whereas the patients with AD exhibited increased ReHo within the right orbital part of frontal regions. Correlations between these three clusters with attention exhibited distinct patterns according to the dementia subtype, as did attention indices with significance in predicting global cognition. In summary, our study suggested that worse attention performance was associated with functional disconnection within the frontal regions among patients with SIVD than in those with AD. Frontal functional disconnection may underlie the pathogenesis responsible for defective divided attention, vigilance/sustained attention, and notable within-group variations identified in SIVD.

Bright Light Therapy and Circadian Cycles in Institutionalized Elders

BACKGROUND

Bright light therapy has been found to be an efficient method to improve the main parameters of circadian rhythms. However, institutionalized elders may suffer reduced exposure to diurnal light, which may impair their circadian rhythms, cognitive performance, and general health status.

OBJECTIVES

To analyze the effects of 5 days of morning exposure for 90 min to bright light therapy (BLT) applied to institutionalized elderly subjects with mild/moderate cognitive impairment.

SUBJECTS

Thirty-seven institutionalized subjects of both sexes, aged 70-93 years.

METHODS

The study lasted three consecutive weeks. During the second week the subjects were submitted to BLT (7000-10,000 lux at eye level) on a daily basis. Cognition, attention, and sleep quality were evaluated at the beginning of the first and third week. Circadian variables were recorded continuously throughout the 3 weeks. Non-invasive holders and validated tests were used to analyze the variables studied.

RESULTS

After BLT we have found significant improvements in general cognitive capabilities, sleep quality and in the main parameters of the subject's circadian rhythms. The results show that merely 90 min of BLT for five days seems to achieve a significant improvement in a constellation of circadian, sleep, health, and cognitive factors.

CONCLUSION

Bright light therapy is an affordable, effective, fast-acting therapy for age-related disturbances, with many advantages over pharmacological alternatives. We hypothesize these effects were the result of activating the residual activity of their presumably weakened circadian system.

The Weakened Relationship Between Prestimulus Alpha Oscillations and Response Time in Older Adults With Mild Cognitive Impairment

Background: Prestimulus alpha oscillations associated with preparatory attention have an impact on response time (RT). However, little is known about whether there is a deficit in the relationship between prestimulus alpha oscillations and RT in older adults with mild cognitive impairment (MCI).

Method: We collected electroencephalography (EEG) data from 28 older adults with MCI and 28 demographically matched healthy controls (HCs) when they were performing an Eriksen flanker task. For each participant, single-trial prestimulus alpha power was calculated for combinations of congruency (congruent vs. incongruent) and response speed (fast vs. slow).

Result: Statistical analysis indicated that prestimulus alpha power was significantly lower for fast trials than slow trials in HCs but not in older adults with MCI. The Fisher’s z scores of the within-subject correlation coefficients between single-trial prestimulus alpha power and RT were significantly larger in HCs than in older adults with MCI. In addition, machine learning analyses indicated that prestimulus alpha power and its correlation with RT could serve as features to distinguish older adults with MCI from HCs and to predict performance on some neuropsychological tests.

Conclusion: The reduced correlation between prestimulus alpha activity and RT suggests that older adults with MCI experience impaired preparatory attention.

Digital assessment of working memory and processing speed in everyday life: Feasibility, validation, and lessons-learned

OBJECTIVES

Cognitive functioning is often impaired in mental and neurological conditions and might fluctuate throughout the day. An existing experience-sampling tool was upgraded to assess individual's cognition in everyday life. The objectives were to test the feasibility and validity of two momentary cognition tasks.

METHODS

The momentary Visuospatial Working Memory Task (mVSWMT) and momentary Digit Symbol Substitution Task (mDSST) were add-ons to an experience sampling method (ESM) smartphone app. Healthy adults (n = 49) between 19 and 73 years of age performed the tasks within an ESM questionnaire 8 times a day, over 6 consecutive days. Feasibility was determined through completion rate and participant experience. Validity was assessed through contextualization of cognitive performance within intrapersonal and situational factors in everyday life.

FINDINGS

Participants experienced the tasks as pleasant, felt motivated, and the completion rate was high (71%). Social context, age, and distraction influenced cognitive performance in everyday life. The mVSWMT was too difficult as only 37% of recalls were correct and thus requires adjustments (i.e. fixed time between encoding and recall; more trials per moment). The mDSST speed outcome seems the most sensitive outcome measure to capture between- and within-person variance.

CONCLUSIONS

Short momentary cognition tasks for repeated assessment are feasible and hold promise, but more research is needed to improve validity and applicability in different samples. Recommendations for teams engaging in the field include matching task design with traditional neuropsychological tests and involving a multidisciplinary team as well as users. Special attention for individual needs can improve motivation and prevent frustration. Finally, tests should be attractive and competitive to stimulate engagement, but still reflect actual cognitive functioning.

Home-based evaluation of executive function (Home-MET) for older adults with mild cognitive impairment

INTRODUCTION

Executive function helps older adults maintain their activities of daily living by making plans, setting goals, and carrying them out successfully. It is important for their independence in community living.

METHODS

With a carefully match-group of 80 mild cognitive impaired with 80 health control subjects. The home-based evaluation of executive function (Home-MET) was validated in subjects' own living environment.

RESULTS

This Home-MET showed significant correlation in the assessment of attention control that was assessing by Test of Everyday Attention (TEA) (r = .86, p < .01), with working memory that was assessed with Trail Making Test (TMT) (r = .72, p < .01), with inhibitory control that was assessing with Stroop Test (r = .86, p < .01), with individuals' functional disability was assessed by Chinese Disability Assessment of Dementia (CDAD) (r = .77, p < .01) and cognitive assessment was assessed by Hong Kong Montreal Cognitive Assessment (HK-MoCA) (r = .88, p < .01). By benchmarking with the validated performance-based executive function assessment, the Home-MET shows significant correlation (r = .92, p < .05) with the executive function test in a standard environment in hospital, i.e. the Chinese Multiple Errands Test (the Chinese-MET). The two-stage hierarchical linear regression model with backward method showed functional disability was a marginally significant predictor (p < .059) for the Home-MET with regression model showed with R² = .93.

CONCLUSION

Results indicated the Home-MET, can provide an objective measure of executive function for subjects with mild cognitive impairment in participants' own home environment.

Are We There Yet? Immersive Virtual Reality to Improve Cognitive Function in Dementia and Mild Cognitive Impairment

Background and Objectives

Cognitive training therapies may delay cognitive deterioration in dementia. There is potential to enhance delivery through immersive virtual reality (IVR), as removing potential distractors for cognitively impaired individuals can enhance their experience, resulting in increased engagement. Evidence in this field is emerging and not yet synthesized. We aimed to summarize research investigating the use of IVR in dementia to evaluate the current extent of use, acceptability, feasibility, and potential effectiveness. We also aimed to identify gaps in current research and to create a set of recommendations in utilizing this therapy.

Research Design and Methods

A systematic literature review was conducted. Our review was registered with PROSPERO, registration number: CRD42019122295. We undertook searches of five databases, article references, and citations. Key authors in the field of health care VR were also contacted to identify additional papers. Articles were assessed for inclusion by two researchers independently. Data were extracted using standardized forms.

Results

Our search identified a total of 2,824 citations, following screening for duplicates and application of inclusion and exclusion criteria, five studies were included for analysis. Included studies were heterogeneous, with small sample sizes and mixed outcomes.

Discussion and Implications

We were unable to reach definitive conclusions over the use, acceptability, and effectiveness of IVR for dementia and mild cognitive impairment. Future studies should focus on ensuring their interventions are truly immersive, developing more robust controls and account for the rapid rate of obsolescence in digital technologies.

Learning and Personalizing Socially Assistive Robot Behaviors to Aid with Activities of Daily Living

Socially assistive robots can autonomously provide activity assistance to vulnerable populations, including those living with cognitive impairments. To provide effective assistance, these robots should be capable of displaying appropriate behaviors and personalizing them to a user's cognitive abilities. Our research focuses on the development of a novel robot learning architecture that uniquely combines learning from demonstration ( LfD ) and reinforcement learning ( RL ) algorithms to effectively teach socially assistive robots personalized behaviors. Caregivers can demonstrate a series of assistive behaviors for an activity to the robot, which it uses to learn general behaviors via LfD . This information is used to obtain initial assistive state-behavior pairings using a decision tree. Then, the robot uses an RL algorithm to obtain a policy for selecting the appropriate behavior personalized to the user's cognition level. Experiments were conducted with the socially assistive robot Casper to investigate the effectiveness of our proposed learning architecture. Results showed that Casper was able to learn personalized behaviors for the new assistive activity of tea-making, and that combining LfD and RL algorithms significantly reduces the time required for a robot to learn a new activity.

Dysexecutive syndrome in amnesic mild cognitive impairment: a multicenter study

BACKGROUND

Executive functions (EF) in Alzheimer's disease (AD), classically related to the prefrontal cortex, have been forgotten in mild stages, given more importance to temporal lobe associated disorders, such as memory. The study of disexecutive syndrome (DS) has been relegated to advanced stages of the disease. Our goal is to demonstrate that EF are already present in amnesic mild cognitive impairment (aMCI). Furthermore, we are interested in knowing whether poor scores in EF tests are related to the progression to AD or another kind of dementia.

METHODS

We studied patients with aMCI (n = 81) and healthy controls (n = 142) from neurological departments of several centers of Basque Country with a cross-sectional design. Patients underwent a complete neuropsychological evaluation, neuroimaging testing APOE genotype and 3 year of prospective follow-up.

RESULTS

In the first visit, patients with aMCI showed more alterations in tests that evaluate EF such as Stroop, trail-making and categorical verbal fluency. More alterations were also found in NPI scale (P <0.05). Stroop and Trail-Making test were not associated with the future development of AD, but fluency (p = 0.01) and apathy (p = 0.031) did. No patient developed a different kind of dementia different from AD.

CONCLUSIONS

DS is a broad concept not confined to frontal lobes, and can be found in early stages of aMCI. DS impacts negatively on patient autonomy and may have prognostic value.

Cognitive Translation Using the Rodent Touchscreen Testing Approach

The development of novel therapeutic avenues for the treatment of cognitive deficits in psychiatric and neurodegenerative disease is of high importance, yet progress in this field has been slow. One reason for this lack of success may lie in discrepancies between how cognitive functions are assessed in experimental animals and humans. In an attempt to bridge this translational gap, the rodent touchscreen testing platform is suggested as a translational tool. Specific examples of successful cross-species translation are discussed focusing on paired associate learning (PAL), the 5-choice serial reaction time task (5-CSRTT), the rodent continuous performance task (rCPT) and reversal learning. With ongoing research assessing the neurocognitive validity of tasks, the touchscreen approach is likely to become increasingly prevalent in translational cognitive research.

Evaluating attention in delirium: A comparison of bedside tests of attention

AIM

Impaired attention is a core diagnostic feature for delirium. The present study examined the discriminating properties for patients with delirium versus those with dementia and/or no neurocognitive disorder of four objective tests of attention: digit span, vigilance "A" test, serial 7s subtraction and months of the year backwards together with global clinical subjective rating of attention.

METHODS

This as a prospective study of older patients admitted consecutively in a general hospital. Participants were assessed using the Confusion Assessment Method, Delirium Rating Scale-98 Revised and Montreal Cognitive Assessment scales, and months of the year backwards. Pre-existing dementia was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders fourth edition criteria.

RESULTS

The sample consisted of 200 participants (mean age 81.1 ± 6.5 years; 50% women; pre-existing cognitive impairment in 126 [63%]). A total of 34 (17%) were identified with delirium (Confusion Assessment Method +). The five approaches to assessing attention had statistically significant correlations (P < 0.05). Discriminant analysis showed that clinical subjective rating of attention in conjunction with the months of the year backwards had the best discriminatory ability to identify Confusion Assessment Method-defined delirium, and to discriminate patients with delirium from those with dementia and/or normal cognition. Both of these approaches had high sensitivity, but modest specificity.

CONCLUSION

Objective tests are useful for prediction of non-delirium, but lack specificity for a delirium diagnosis. Global attentional deficits were more indicative of delirium than deficits of specific domains of attention. Geriatr Gerontol Int 2016; 16: 1028-1035.

The BDNF Val66Met polymorphism moderates the relationship between cognitive reserve and executive function

The concept of cognitive reserve (CR) has been proposed to account for observed discrepancies between pathology and its clinical manifestation due to underlying differences in brain structure and function. In 433 healthy older adults participating in the Tasmanian Healthy Brain Project, we investigated whether common polymorphic variations in apolipoprotein E (APOE) or brain-derived neurotrophic factor (BDNF) influenced the association between CR contributors and cognitive function in older adults. We show that BDNF Val66Met moderates the association between CR and executive function. CR accounted for 8.5% of the variance in executive function in BDNF Val homozygotes, but CR was a nonsignificant predictor in BDNF Met carriers. APOE polymorphisms were not linked to the influence of CR on cognitive function. This result implicates BDNF in having an important role in capacity for building or accessing CR.

Neural Correlates of Unsuccessful Memory Performance in MCI

People with mild cognitive impairment (MCI) are at an elevated risk of developing Alzheimer’s disease or other forms of dementia. Although the neural correlates of successful memory performance in MCI have been widely investigated, the neural mechanisms involved in unsuccessful memory performance remain unknown. The current study examines the differences between patients suffering from stable amnestic MCI with multiple deficit syndromes and healthy elderly controls in relation to the neural correlates of both successful and unsuccessful encoding and recognition. Forty-six subjects (27 controls, 19 MCI) from the HelMA (Helmholtz Alliance for Mental Health in an Aging Society) completed a comprehensive neuropsychological test battery and participated in an fMRI experiment for associative face-name memory. In patients, the areas of frontal, parietal, and temporal cortices were less involved during unsuccessful encoding and recognition. A temporary dysfunction of the top-down control of frontal or parietal (or both) areas is likely to result in a non-selective propagation of task-related information to memory.

A combined effect of two Alzheimer's risk genes on medial temporal activity during executive attention in young adults

A recent history of failed clinical trials suggests that waiting until even the early stages of onset of Alzheimer's disease may be too late for effective treatment, pointing to the importance of early intervention in young people. Early intervention will require markers of Alzheimer's risk that track with genotype but are capable of responding to treatment. Here, we sought to identify a functional MRI signature of combined Alzheimer's risk imparted by two genetic risk factors. We used a task of executive attention during fMRI in participants genotyped for two Alzheimer's risk alleles: APOE-ε4 and CLU-C. Executive attention is a sensitive indicator of the progression of Alzheimer's even in the early stages of mild cognitive impairment, but has not yet been investigated as a marker of Alzheimer's risk in young adults. Functional MRI revealed that APOE-ε4 and CLU-C had an additive effect on brain activity such that increased combined genetic risk was associated with decreased brain activity during executive attention, including in the medial temporal lobe, a brain area affected early in Alzheimer's pathogenesis.

Aspects of Attention Predict Real-World Task Performance in Alzheimer's Disease

More research is needed to examine the relationship between specific neuropsychological functions and observation-based daily activity tests in patients with Alzheimer's disease (AD). Fifty-six patients with AD were administered tests of attention and processing speed and an observation-based activities-of-daily-living (ADL) task. Complex short-term attention capacity best predicted real-world task performance, accounting for several domains of ADL functioning. These results suggest that complex attention requiring working-memory systems, but not simple attention or processing speed, account for moderate portions of variability in daily task performance. These results may aid in understanding the attentional processes required for performing daily activities and can be useful to health care professionals in treatment planning.

Paying more attention to attention: towards more comprehensive cognitive translation using mouse models of Alzheimer's disease

The cognitive phenotyping of mouse models of Alzheimer's disease (AD) currently focuses on impairments in learning and memory. However, AD is not simply a memory disorder, but other cognitive domains, and in particular attention, can also be impaired even at very early stages of the disease. In this review we argue for the benefits of including other constructs, and in particular attention, in preclinical studies to identify drug targets and disease mechanisms of AD in mouse models. First we give a brief account of the evidence for attentional deficits in AD; we then summarise methods to assess equivalent aspects of attention in mice, followed by a review of recent evidence for attentional impairments in widely used mouse models of AD. We conclude by suggesting that a multidimensional approach to cognitive assessment in preclinical models, in which a number of aspects of cognition are investigated while confounding factors are minimized, is becoming increasingly feasible and may contribute significantly towards the development of more targeted therapeutic interventions.

DESIGNING INTELLIGENT SOCIALLY ASSISTIVE ROBOTS AS EFFECTIVE TOOLS IN COGNITIVE INTERVENTIONS

Recently, there has been a growing body of research that supports the effectiveness of using non-pharmacological cognitive and social training interventions to reduce the decline of or improve brain functioning in individuals suffering from cognitive impairments. However, implementing and sustaining such interventions on a long-term basis is difficult as they require considerable resources and people, and can be very time-consuming for healthcare staff. Our research focuses on making these interventions more accessible to healthcare professionals through the aid of robotic assistants. The objective of our work is to develop an intelligent socially assistive robot with abilities to recognize and identify human affective intent to determine its own appropriate emotion-based behavior while engaging in assistive interactions with people. In this paper, we present the design of a novel human-robot interaction (HRI) control architecture that allows the robot to provide social and cognitive stimulation in person-centered cognitive interventions. Namely, the novel control architecture is designed to allow a robot to act as a social motivator by encouraging, congratulating and assisting a person during the course of a cognitively stimulating activity. Preliminary experiments validate the effectiveness of the control architecture in providing assistive interactions during a HRI-based person-directed activity.

An examination of an enhancing effect of music on attentional abilities in older persons with mild cognitive impairment

While the effect of listening to music on cognitive abilities is highly debated, studies reporting an enhancing effect of music in elderly populations appear to be more consistent. In this study, the effects of listening to music on attention in groups of cognitively normal older adults and those with mild cognitive impairment were considered. Participants were exposed to both a music and silence condition, and after each condition performed Digit Span and Coding tasks which require attention for maximal performance. The hypothesis that listening to music, compared to a silence condition, enhances performance was not supported for either group. Various explanations for these findings are considered.

Spousal interrelations in self-reports of cognition in the context of marital problems

BACKGROUND

Problems with cognitive function are common among older adults, yet there is little research assessing the extent to which the cognitive problems of older husbands and wives are related to those of their partners and whether any observed relationships are moderated by gender or marital quality.

OBJECTIVES

Our purpose was to analyze longitudinal relationships between older spouses' cognitive function and the cognitive function of their partners 5 years later, as well as to assess moderating roles of gender and marital quality.

METHODS

The subjects were 378 community-dwelling couples aged 46-89 years at baseline who were followed for 5 years. Cognitive function was measured with a scale assessing problems remembering names, finding the right word, misplacing things and paying attention. Marital quality was assessed by comparing those reporting marital problems often or sometimes with those reporting marital problems rarely or never. All data were collected by self-report. Statistical models adjusted for paired data where appropriate and included partner cognitive function, age, chronic conditions and financial hardship. Stratified models assessed moderating roles of gender and marital problems.

RESULTS

We found a negative relationship between husbands' baseline lower cognitive function and wives' subsequent cognitive function but only for the wives reporting marital problems. We found no comparable relationship between wives' baseline lower cognitive function and their husbands' subsequent cognitive function.

CONCLUSIONS

Our gender-specific finding for wives is consistent with the gender differences noted in 2 previous studies. The limitation to wives with problems in their marriages is a new finding and might follow increased stress and depression responding to changes in their husbands' cognitive functioning.

The MMSE orientation for time domain is a strong predictor of subsequent cognitive decline in the elderly

BACKGROUND

The mini-mental state exam (MMSE) has been used to address questions such as determination of appropriate cutoff scores for differentiation of individuals with intact cognitive function from patients with dementia and rate of cognitive decline. However, little is known about the relationship of performance in specific cognitive domains to subsequent overall decline.

OBJECTIVE

To examine the specific and/or combined contribution of four MMSE domains (orientation for time, orientation for place, delayed recall, and attention) to prediction of overall cognitive decline on the MMSE.

METHODS

Linear mixed models were applied to 505 elderly nursing home residents (mean age = 85, > 12 years education = 27%; 79% F, mean follow-up = 3.20 years) to examine the relationship between baseline scores of these domains and total MMSE scores over time.

RESULTS

Orientation for time was the only domain significantly associated with MMSE decline over time. Combination of poor delayed recall with either attention or orientation for place was associated with significantly increased decline on the MMSE.

CONCLUSIONS

The MMSE orientation for time predicts overall decline on MMSE scores over time. A good functioning domain added to good functioning delayed recall was associated with slower rate of decline.

Detection of MCI in the clinic: evaluation of the sensitivity and specificity of a computerised test battery, the Hopkins Verbal Learning Test and the MMSE

INTRODUCTION

the sensitive detection of mild cognitive impairment (MCI) in older adults is an important problem that requires objective assessment. We evaluated whether the computerised cognitive test battery, CogState, was as sensitive to MCI as two well-validated 'paper-and-pencil' tests, the Hopkins Verbal Learning Test (HVLT) and the Mini-Mental Status Examination (MMSE).

METHODS

these tests were administered with a subjective memory questionnaire and an 'Activities of Daily Living' scale to 21 individuals with MCI and 98 cognitively healthy controls matched for sex, education and IQ levels. The sensitivity and specificity of the tests and their discrimination between groups were determined.

RESULTS

the HVLT had a maximum discrimination between controls and MCI cases of 90%, compared with 86% for CogState and 65% for the MMSE. Only CogState showed correlations with subjective memory complaints (SMC) and activities of daily living for the whole cohort when controlled for age, sex and years of education. Logistic regression analyses showed that diagnosis (control:MCI) was predicted by HVLT and a CogState ratio score. Age was a significant predictor of HVLT performance, while age and SMC predicted CogState performance. The computerised test battery was well tolerated by older adults, but presentation speed was a limiting factor for some participants.

CONCLUSIONS

overall, we conclude that the HVLT has better sensitivity for the detection of MCI in older adults than the CogState, but that CogState may enable the identification of cognitive deficits above and beyond impairments in memory.

Study on the Behavioural Assessment of the Dysexecutive Syndrome (BADS) performance in healthy individuals, Mild Cognitive Impairment and Alzheimer's disease: A preliminary study

Executive deficits as well as deficits in episodic memory characterize the initial phases of Alzheimer Disease (AD) and are clinically correlated to neuropsychiatric symptoms and functional loss. Patients with Mild Cognitive Impairment present more problems as to inhibitory response control, switching and cognitive flexibility.

OBJECTIVE

To compare performance on the BADS with performance on other executive functional tests among patients with mild Alzheimer's disease, Amnestic Mild Cognitive Impairment (aMCI) to performance of control individuals and to examine discriminative capacity of BADS among these groups.

METHODS

The BADS was performed by 35 healthy controls, 13 patients with aMCI, and 16 mild probable AD patients. Besides performing the BADS, subjects underwent neuropsychological evaluation which comprised: the Dementia Rating Scale (DRS), verbal fluency by phonemic categories (F.A.S) and Concentrated Attention Test (CA).

RESULTS

There were no differences among groups by educational level, but performance differed for age (p<0.01). No difference between healthy controls and aMCI patients was found on total scores or subitems of the BADS. A significant difference was observed between aMCI and AD patients (p<0.05) and between controls and AD patients (p<0.05) on total and standard scores.

CONCLUSIONS

Performance on the BADS differed between healthy individuals and mild AD patients. The BADS proved to be a sensitive method for discriminating AD from aMCI.