The Toronto Cognitive Assessment (TorCA): normative data and validation to detect amnestic mild cognitive impairment

The Piano Man: A Case Report of Anterior Thalamic Infarct with Dementia and Preserved Music Ability

OBJECTIVE

The thalamus is the integrative hub of the brain with reciprocal connections throughout the cortex. This case report describes a right-handed 81-year-old male patient who experienced sudden onset cognitive impairment following a focal left anterior thalamic infarct.

METHODS

With consent/assent, the patient was seen for a short neuropsychological assessment 6 weeks post stroke. Neuropsychological assessment included review of medical history, collateral intake, the Toronto Cognitive Assessment, Frontal Systems Behavior Scale-Family Rating Form, the Neuropsychiatric Inventory Questionnaire, and piano performance.

RESULTS

The assessment revealed impaired performance on measures of orientation, memory, executive function, and language, as well as symptoms including hallucinations, apathy, and hypersomnolence, consistent with thalamic dementia. Remarkably, in this context, the patient maintained an ability to play piano and read music.

CONCLUSIONS

The case has implications for understanding the complex integrative functions of the thalamus, including how profound impairment can simultaneously present with cognitive strengths that may not be captured by performance on neuropsychological testing. This case also suggests that magnetic resonance imaging may be indicated in cases presenting with vascular risk factors and sudden onset cognitive impairment, given that computed tomography may not be sensitive to small subcortical infarcts.

Design and Feasibility Analysis of a Smartphone-Based Digital Cognitive Assessment Study in the Framingham Heart Study

BACKGROUND

Smartphone-based digital technology is increasingly being recognized as a cost-effective, scalable, and noninvasive method of collecting longitudinal cognitive and behavioral data. Accordingly, a state-of-the-art 3-year longitudinal project focused on collecting multimodal digital data for early detection of cognitive impairment was developed.

METHODS AND RESULTS

A smartphone application collected 2 modalities of cognitive data, digital voice and screen-based behaviors, from the FHS (Framingham Heart Study) multigenerational Generation 2 (Gen 2) and Generation 3 (Gen 3) cohorts. To understand the feasibility of conducting a smartphone-based study, participants completed a series of questions about their smartphone and app use, as well as sensory and environmental factors that they encountered while completing the tasks on the app. Baseline data collected to date were from 537 participants (mean age=66.6 years, SD=7.0; 58.47% female). Across the younger participants from the Gen 3 cohort (n=455; mean age=60.8 years, SD=8.2; 59.12% female) and older participants from the Gen 2 cohort (n=82; mean age=74.2 years, SD=5.8; 54.88% female), an average of 76% participants agreed or strongly agreed that they felt confident about using the app, 77% on average agreed or strongly agreed that they were able to use the app on their own, and 81% on average rated the app as easy to use.

CONCLUSIONS

Based on participant ratings, the study findings are promising. At baseline, the majority of participants are able to complete the app-related tasks, follow the instructions, and encounter minimal barriers to completing the tasks independently. These data provide evidence that designing and collecting smartphone application data in an unsupervised, remote, and naturalistic setting in a large, community-based population is feasible.

The Rossy Progressive Supranuclear Palsy Centre: Creation and Initial Experience

OBJECTIVE

To describe the development and initial experience of a clinical research program in progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) in Canada: The Rossy PSP Centre, to share the data acquisition tools adopted, and to report preliminary results.

METHODS

Extensive demographic and longitudinal clinical information is collected every 6 months using standardized forms. Biofluids are collected for biobanking and genetic analysis, and many patients are enrolled in neuroimaging research protocols. Brain donation is an important component of the program, and standardized processing protocols have been established, including very short death to autopsy times in patients undergoing medical assistance in dying.

RESULTS

Between Oct 2019 and Dec 2021, 132 patients were screened, 91 fulfilling criteria for PSP and 19 for CBS; age 71 years; 41% female; duration 5 years, age-of-onset 66 years. The most common symptoms at onset were postural instability and falls (45%), cognitive-behavioral changes (22%), and Parkinsonism (9%). The predominant clinical phenotype was Richardson syndrome (82%). Levodopa and amantadine resulted in partial and short-lasting benefit.

CONCLUSIONS

The Rossy PSP Centre has been established to advance clinical and basic research in PSP and related tauopathies. The extent of the clinical data collected permits deep phenotyping of patients and allows for future clinical and basic research. Preliminary results showed expected distribution of phenotypes, demographics, and response to symptomatic treatments in our cohort. Longitudinal data will provide insight into the early diagnosis and management of PSP. Future steps include enrollment of patients in earlier stages, development of biomarkers, and fast-tracking well-characterized patients into clinical trials.

Investigating changes in cognition associated with the use of CPAP in cognitive impairment and dementia: A retrospective study

STUDY OBJECTIVES

To characterize the impact of CPAP use on cognition in a clinical cohort with obstructive sleep apnea (OSA) and cognitive impairment due to neurodegenerative or vascular etiologies after controlling for baseline sleepiness.

METHODS

We retrospectively analyzed data from 171 patients with cognitive impairment and an OSA diagnosis confirmed with in-laboratory polysomnography or home sleep apnea testing (mean age 69.8 ± 10.6; 66% male) who were eligible to use CPAP. Baseline and follow-up Epworth Sleepiness Score (ESS), Montreal Cognitive Assessment (MoCA), and Mini-Mental Status Examination (MMSE) were obtained from clinical and research visits conducted before and after CPAP initiation. Good CPAP adherence was defined as CPAP use ≥4 h/night, for 7 days/week at follow-up. Associations between CPAP adherence and follow-up cognitive scores were analyzed using multivariable linear mixed-effects models.

RESULTS

After adjusting for age, sex, body mass index, baseline ESS, duration of CPAP therapy, relevant comorbidities and the random effect of research study cohort, good CPAP adherence (compared to poor CPAP adherence or no use of CPAP) for a duration of 2-12 months was associated with a 2.3-point (1.2-3.3 95% CI) higher follow-up MoCA score (p < 0.001) and a 1.2-point (0.3-2.3 95% CI) higher follow-up MMSE score (p = 0.01).

CONCLUSIONS

In patients with OSA and cognitive impairment due to a neurodegenerative or vascular etiology, use of CPAP is associated with improved cognitive outcomes. The findings of this study may aid in motivating patients to use CPAP and support future randomized controlled trials in this area.

Touchscreen Cognitive Tools for Mild Cognitive Impairment and Dementia Used in Primary Care Across Diverse Cultural and Literacy Populations: A Systematic Review

BACKGROUND

Touchscreen cognitive tools opened new promising opportunities for the early detection of cognitive impairment; however, most research studies are conducted in English-speaking populations and high-income countries, with a gap in knowledge about their use in populations with cultural, linguistic, and educational diversity.

OBJECTIVE

To review the touchscreen tools used in primary care settings for the cognitive assessment of mild cognitive impairment (MCI) and dementia, with a focus on populations of different cultures, languages, and literacy.

METHODS

This systematic review was conducted following the PRISMA guidelines. Studies were identified by searching across MEDLINE, EMBASE, EBSCO, OVID, SCOPUS, SCIELO, LILACS, and by cross-referencing. All studies that provide a first-level cognitive assessment for MCI and dementia with any touchscreen tools suitable to be used in the context of primary care were included.

RESULTS

Forty-two studies reporting on 30 tools and batteries were identified. Substantial differences among the tools emerged, in terms of theoretical framework, clinical validity, and features related to the application in clinical practice. A small proportion of the tools are available in multiple languages. Only 7 out of the 30 tools have a multiple languages validation. Only two tools are validated in low-educated samples, e.g., IDEA and mSTS-MCI.

CONCLUSION

General practitioners can benefit from touchscreen cognitive tools. However, easy requirements of the device, low dependence on the examiner, fast administration, and adaptation to different cultures and languages are some of the main features that we need to take into consideration when implementing touchscreen cognitive tools in the culture and language of underrepresented populations.

A Cost-Benefit Analysis of a Group Memory Intervention for Healthy Older Adults with Memory Concerns

This study examines whether memory intervention programs can mitigate health care costs. Research suggests these programs translate to a decreased intention of older adults who are worried about age-normal memory changes to seek traditional outlets for medical/psychiatric help. We employed a cost-benefit analysis approach to analyze the effectiveness of a memory intervention program within Ontario. We leveraged estimates of decreased intentionality to seek physician care following a community-based memory intervention with physician billing profiles to calculate the potential cost savings to the province's health care system. The intervention studied was found to reduce provincial health care spending by $6,094 per program group. This amount exceeds $121.25 in direct costs per attendee associated with administering five program sessions. This analysis justifies further research on how community-based memory and aging programs can offer low-cost solutions to help individuals cope with subjective memory complaints and assist the health care system in prioritizing care for aging patients.

Preventing post-stroke dementia. The MARCH Trial. Protocol and statistical analysis plan of a randomized clinical trial testing the safety and efficacy of Maraviroc in post-stroke cognitive impairment

Background:

Current evidence suggest that 25%–33% of stroke-survivors develop post-stroke cognitive impairment (PSCI). The licensed drug Maraviroc, a CCR5-antagonist, is postulated to act via a neuroprotective mechanism that may offer the potential of preventing progression to vascular dementia. Our hypothesis: Maraviroc may have the potential to augment learning skills and cognitive performance by affecting synaptic plasticity, along with neuro-inflammatory modulation in patients with cerebral small vessel disease (SVD) and PSCI.

Design:

MARCH is a multi-center, double-blind randomized-control Phase-II trial of Maraviroc 150 or 600 mg/day versus placebo for 12-months in five stroke centers in Israel. Included are patients diagnosed with recent (1–24 months) subcortical stroke who experience mild PSCI and have evidence of white matter lesions and SVD on neuroimaging.

Outcomes:

Primary outcomes: 1. Change in cognitive scores. 2. Drug related adverse events. Secondary outcomes: change in functional and affective scores, MRI-derived measures, inflammatory markers, carotid atherosclerosis, cerebrospinal-fluid biomarkers in a sub-study. A sample size of 60 in each treatment group and 30 in the placebo group (total – 150 participants) provides 80% power between the treatment and the placebo groups.

Conclusions:

The results of this work could lead to a novel, readily available, therapeutic avenue to reduce PSCI, and possibly other pathologies. This study will test safety and effectiveness of Maraviroc in limiting cognitive deterioration and/or post stroke cognitive impairment in patients with cerebral small vessel disease.

Schedule:

First-patient first-visit was May 2021. Recruitment to complete in 2023, follow-up to complete in 2024.

Technology-based Neurocognitive Assessment of the Elderly: a Mini Review

Neurocognitive disorders in the elderly are on the rise all over the world. Neuropsychological assessment is vital to monitoring the progress of cognitive deficits. Over the years, there has been significant development in neuropsychological assessment to predict the development and progression of MCI and dementia. One such area of recent advancement in the field of neuropsychology is technology-based assessment. There are several types of technology-based assessments available based on the type of usage, site of the assessment, type of administration, type of device used for assessment, etc. Virtual reality-based assessments and digital assessments of neurocognitions for early identification of subtle cognitive deficits in patients with mild cognitive impairment (MCI) and major neurocognitive disorders (MND) represent two newly developed technologies. A few studies have demonstrated their efficacy; however, there remain several limitations and drawbacks to their usage within the elderly population. In this review, we have briefly discussed technology-based neuropsychological assessment, along with their usage and limitations.

Diagnostic Precision in the Detection of Mild Cognitive Impairment: A Comparison of Two Approaches

OBJECTIVE

This study compared diagnostic rates and clinical predictors of discrepancies between diagnoses conferred via: 1) a comprehensive neuropsychological evaluation and National Institute on Aging-Alzheimer's Association (NIA-AA) criteria versus 2) a cognitive screener and Diagnostic Statistical Manual of Mental Disorders (DSM-5) criteria.

DESIGN

Cross-sectional examination of baseline data from the Prevention of Alzheimer's dementia (AD) using Cognitive remediation and transcranial direct current stimulation in Mild Cognitive Impairment (MCI) and Depression (PACt-MD; ClinicalTrials.gov Identifier: NCT02386670) trial.

SETTING

Five geriatric psychiatry and memory clinics located at academic hospitals affiliated with the Department of Psychiatry, University of Toronto.

PARTICIPANTS

Older adults (N = 431) with a history of major depressive disorder (MDD) in remission, MCI, or both.

MEASUREMENTS

Main outcome was a comparison of NIA-AA diagnostic rates of MCI or dementia versus DSM-5 rates of mild or major neurocognitive disorder. Secondary analyses examined demographic, race, gender, premorbid intellectual ability, psychosocial, health-related, and genetic predictors of discrepancy between DSM-5 and NIA-AA diagnoses.

RESULTS

There were 103 (23.8%) discrepant cases, with most (91; 88.3%) of these discrepant cases reflecting more impairment with the detailed neuropsychological testing and NIA-AA criteria. Discrepancies were more likely in individuals with a history of MDD or who had at least one ApoE4 allele.

CONCLUSION

The NIA-AA criteria, in conjunction with comprehensive neuropsychological testing, identified a greater prevalence of cognitive impairment than DSM-5 criteria, in conjunction with the Montreal Cognitive Assessment. Detailed neuropsychological evaluations are recommended for older adults who have a history of MDD or a genetic vulnerability to dementia.

Evaluation of Available Cognitive Tools Used to Measure Mild Cognitive Decline: A Scoping Review

Cognitive decline is a broad syndrome ranging from non-pathological/age-associated cognitive decline to pathological dementia. Mild cognitive impairment MCI) is defined as the stage of cognition that falls between normal ageing and dementia. Studies have found that early lifestyle interventions for MCI may delay its pathological progression. Hence, this review aims to determine the most efficient cognitive tools to discriminate mild cognitive decline in its early stages. After a systematic search of five online databases, a total of 52 different cognitive tools were identified. The performance of each tool was assessed by its psychometric properties, administration time and delivery method. The Montreal Cognitive Assessment (MoCA, n = 15), the Mini-Mental State Examination (MMSE, n = 14) and the Clock Drawing Test (CDT, n = 4) were most frequently cited in the literature. The preferable tools with all-round performance are the Six-item Cognitive Impairment Test (6CIT), MoCA (with the cut-offs of ≤24/22/19/15.5), MMSE (with the cut-off of ≤26) and the Hong Kong Brief Cognitive Test (HKBC). In addition, SAGE is recommended for a self-completed survey setting whilst a 4-point CDT is quick and easy to be added into other cognitive assessments. However, most tools were affected by age and education levels. Furthermore, optimal cut-off points need to be cautiously chosen while screening for MCI among different populations.

The Impact of Memory Change on Everyday Life Among Older Adults: Association with Cognition and Self-Reported Memory

OBJECTIVES

Many older adults experience memory changes that can have a meaningful impact on their everyday lives, such as restrictions to lifestyle activities and negative emotions. Older adults also report a variety of positive coping responses that help them manage these changes. The purpose of this study was to determine how objective cognitive performance and self-reported memory are related to the everyday impact of memory change.

METHODS

We examined these associations in a sample of 94 older adults (age 60-89, 52% female) along a cognitive ability continuum from normal cognition to mild cognitive impairment.

RESULTS

Correlational analyses revealed that greater restrictions to lifestyle activities (|rs| = .36-.66), more negative emotion associated with memory change (|rs| = .27-.76), and an overall greater burden of memory change on everyday living (|rs| = .28-.61) were associated with poorer objective memory performance and lower self-reported memory ability and satisfaction. Performance on objective measures of executive attention was unrelated to the impact of memory change. Self-reported strategy use was positively related to positive coping with memory change (|r| = .26), but self-reported strategy use was associated with more negative emotions regarding memory change (|r| = .23).

CONCLUSIONS

Given the prevalence of memory complaints among older adults, it is important to understand the experience of memory change and its impact on everyday functioning in order to develop services that target the specific needs of this population.

Feasibility of unattended home sleep apnea testing in a cognitively impaired clinic population

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) increases the risk of developing dementia. Home sleep apnea testing (HSAT) is a convenient and validated method to screen for OSA among cognitively well individuals; however, it is unknown if it is a clinically feasible and practical approach in clinic patients with cognitive impairment. We evaluated if HSAT was a feasible and practical approach to screen for OSA in clinic patients with cognitive impairment.

METHODS

Patients with cognitive impairment due to neurodegenerative and/or vascular etiologies completed OSA screening using HSAT. HSAT was considered a feasible technique if ≥ 80% of those who attempted HSAT obtained analyzable data (ie, ≥ 4 hours of flow, effort, and oxygen evaluation), and a practical technique if ≥ 50% of all patients approached for study inclusion obtained analyzable data.

RESULTS

Of the 119 patients who were approached for participation, 83 were enrolled and offered HSAT; 5 did not complete HSAT screening, and the remaining 78 patients attempted HSAT; mean age (± standard deviation) of 72.86 (± 9.89) years and 46% were male. In those that attempted HSAT, 85.9% (67/78) obtained analyzable data and 56.3% (67/119) of eligible patients approached for study inclusion obtained analyzable data.

CONCLUSIONS

HSAT is a feasible and practical technique in a clinic population with cognitive impairment. As OSA is a modifiable risk factor for patients with dementia, HSAT has the potential to lead to expedited treatment for OSA, which may potentially improve health-related outcomes such as cognition.

CCCDTD5 recommendations on early and timely assessment of neurocognitive disorders using cognitive, behavioral, and functional scales

INTRODUCTION

Earlier diagnosis of neurocognitive disorders and neurodegenerative disease is needed to implement preventative interventions, minimize harm, and reduce risk of exploitation in the context of undetected disease. Along the spectrum from subjective cognitive decline (SCD) to dementia, evidence continues to emerge with respect to detection, staging, and monitoring. Updates to previous guidelines are required for clinical practice.

METHODS

A subcommittee of the 5th Canadian Consensus Conference on Diagnosis and Treatment of Dementia (CCCDTD) reviewed emerging evidence to address the following: (1) Is there a role for screening at-risk patients without clinical concerns? In what context is assessment for dementia appropriate? (2) What tools can be used to evaluate patients in whom cognitive decline is suspected? (3) What important information can be gained from an informant, using which measures? (4) What instruments can be used to get more in-depth information to diagnose mild cognitive impairment (MCI) or dementia? (5) What is the approach to those with cognitive concerns but without objective changes (ie, SCD)? (6) How do we track response to treatment and change over time? The Grading of Recommendations Assessment, Development, and Evaluation system was used to rate quality of the evidence and strength of the recommendations.

RESULTS

We recommend instruments to assess and monitor cognition, behavior, and function across the cognitive spectrum, including reports from patient and informant. We recommend against screening asymptomatic older adults but recommend investigation for self- or informant reports of changes in cognition, emergence of behavioral or psychiatric symptoms, or decline in function or self-care. Standardized assessments should be used for cognitive and behavioral change that have sufficient validity for use in clinical practice.

DISCUSSION

The CCCDTD5 provides evidence-based recommendations for detection, assessment, and monitoring of neurocognitive disorders. Although these guidelines were developed for use in Canada, they may also be useful in other jurisdictions.

Seizures and early onset dementia: D2HGA1 inborn error of metabolism in adults

D‐2‐hydroxyglutaric aciduria type 1 (D2HGA1) is a rare inherited metabolic disorder usually manifesting in infancy/early childhood with seizures and significant central nervous system involvement. We report two siblings with D2HGA1 presenting with mild intellectual disability, and the onset of seizures in adulthood. One of them was misdiagnosed as tuberous sclerosis due to her presentation and the presence of subependymal nodules on brain imaging. Both further developed early onset dementia. This report expands the phenotype of D2HGA1 to include late‐onset seizures and early onset dementia in adults.

Recommendations of the 5th Canadian Consensus Conference on the diagnosis and treatment of dementia

Since 1989, four Canadian Consensus Conferences on the Diagnosis and Treatment of Dementia (CCCDTD) have provided evidence-based dementia guidelines for Canadian clinicians and researchers. We present the results of the 5th CCCDTD, which convened in October 2019, to address topics chosen by the steering committee to reflect advances in the field, and build on previous guidelines. Topics included: (1) utility of the National Institute on Aging research framework for clinical Alzheimer's disease (AD) diagnosis; (2) updating diagnostic criteria for vascular cognitive impairment, and its management; (3) dementia case finding and detection; (4) neuroimaging and fluid biomarkers in diagnosis; (5) use of non-cognitive markers of dementia for better dementia detection; (6) risk reduction/prevention; (7) psychosocial and non-pharmacological interventions; and (8) deprescription of medications used to treat dementia. We hope the guidelines are useful for clinicians, researchers, policy makers, and the lay public, to inform a current and evidence-based approach to dementia.

Association Between Cerebrospinal Fluid Biomarkers and Age-related Brain Changes in Patients with Normal Pressure Hydrocephalus

Our study aimed to: 1)investigate the diagnostic utility of CSF Aβ42, t-tau, and p-tau to differentiate normal-pressure-hydrocephalus(NPH) from Alzheimer’s-disease(AD) and normal-controls; and 2)investigate if age and ventricular size affect the levels of CSF biomarkers in NPH patients. We recruited 131 participants: (a)Suspected-NPH: 72 with ventriculomegaly and clinical symptoms of NPH. These participants were then divided into two groups of 1)Probable-NPH (N = 38) and 2)Unlikely-NPH (N = 34) based on whether participants experienced gait improvement after removal of a large amount of CSF; (b)AD group: 30 participants with CSF biomarkers and cognitive symptoms consistent with AD; (c)Control-group: 29 participants who were cognitively and functionally normal. Lower levels of CSF Aβ42 and p-tau were observed in the probable-NPH compared to the normal controls(444.22 ± 163.3 vs. 1213.75 ± 556.5; and 26.05 ± 9.2 vs. 46.16 ± 13.3 pg/mL; respectively). Lower levels of CSF p-tau and t-tau were found in the probable-NPH compared to the AD(26.05 ± 9.2 vs. 114.95 ± 28.2; and 193.29 ± 92.3 vs. 822.65 ± 311.5 pg/mL; respectively) but the CSF-Aβ42 was low in both the probable-NPH and AD. CSF-Aβ42 correlated with age and Evans-index only in the probable-NPH(r = 0.460, p = 0.004; and r = −0.530, p = 0.001; respectively). Our study supports the hypothesis that age-related atrophy results in better Aβ42 clearance in the CSF because of the increase in the interstitial space.

Post-Concussion Syndrome and Sleep Apnea: A Retrospective Study

Background: Concussion symptoms typically resolve within 7–10 days, but 10–25% of patients do not fully recover. They can develop post-concussion syndrome (PCS), which includes sleep abnormalities such as obstructive sleep apnea. It is unclear how specific sleep problems manifest in PCS and how it relates to cognition and symptomology. Methods: A retrospective chart review was conducted on PCS patients seen at the University Health Network (UHN) Concussion Clinic and sent for sleep study. Neuropsychology tests, concussion features, PCS symptoms, and demographics were abstracted from clinical charts. Sleep measures were abstracted from the overnight sleep study. Data were analyzed using chi-squared tests and linear regression. Results: Fifty-one patients completed the sleep study; 78% of these were diagnosed with sleep apnea. Patients with sleep apnea reported significantly more memory symptoms. A trend existed for higher total symptom number. Age was significantly different between the two groups. Women and men were equally at risk of being diagnosed with sleep apnea. Conclusions: Sleep apnea is common in PCS patients complaining of non-restorative sleep and/or waking up with headaches. Sleep apnea was associated with more memory symptoms. PCS patients are at higher risk for sleep apnea and sleep study should be considered if complaining of non-restorative sleep and/or waking up with headaches, regardless of sex and other known risk factors.

Association Between Social Cognition Changes and Resting State Functional Connectivity in Frontotemporal Dementia, Alzheimer's Disease, Parkinson's Disease, and Healthy Controls

OBJECTIVE

To determine the relationship between alterations in resting state functional connectivity and social cognition dysfunction among patients with frontotemporal dementia (FTD), Alzheimer's disease (AD), Parkinson's disease (PD), and healthy controls (HC).

METHODS

Fifty-seven participants (FTD = 10, AD = 18, PD = 19, and HC = 10) underwent structural and functional imaging and completed the Awareness of Social Inference Test-Emotion Evaluation Test (TASIT-EET), Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) scale, Revised Self-Monitoring Scale (RSMS), Interpersonal Reactivity Index (IRI), and Social Norms Questionnaire (SNQ). A multi-variate pattern analysis (MVPA) was carried out to determine activation differences between the groups. The clusters from the MVPA were used as seeds for the ROI-to-voxel analysis. Relationship between social cognition deficits and uncinate integrity was also investigated.

RESULTS

BOLD signal activation differed among the four groups of AD, PD, FTD, and HC in the left inferior temporal gyrus-anterior division [L-ITG (ant)], right central opercular cortex (R-COp), right supramarginal gyrus, posterior division (R-SMG, post), right angular gyrus (R-AG), and R-ITG. The BOLD co-activation of the L-ITG (ant) with bilateral frontal pole (FP) and paracingulate gyrus was positively associated with IRI-perspective taking (PT) (r = 0.38, p = 0.007), SNQ total (r = 0.37, p = 0.009), and TASIT-EET (r = 0.47, p < 0.001).

CONCLUSION

Patients with neurodegenerative diseases showed alterations in connectivity in brain regions important for social cognition compared with HCs. Functional connectivity correlated with performance on social cognition tasks and alterations could be responsible for some of the social cognition deficits observed in all neurodegenerative diseases.

Genetic and epigenetic study of an Alzheimer's disease family with monozygotic triplets

Age at onset of Alzheimer's disease is highly variable, and its modifiers (genetic or environmental) could act through epigenetic changes, such as DNA methylation at CpG sites. DNA methylation is also linked to ageing-the strongest Alzheimer's disease risk factor. DNA methylation age can be calculated using age-related CpGs and might reflect biological ageing. We conducted a clinical, genetic and epigenetic investigation of a unique Ashkenazi Jewish family with monozygotic triplets, two of whom developed Alzheimer's disease at ages 73 and 76, while the third at age 85 has no cognitive complaints or deficits in daily activities. One of their offspring developed Alzheimer's disease at age 50. Targeted sequencing of 80 genes associated with neurodegeneration revealed that the triplets and the affected offspring are heterozygous carriers of the risk APOE ε4 allele, as well as rare substitutions in APP (p.S198P), NOTCH3 (p.H1235L) and SORL1 (p.W1563C). In addition, we catalogued 52 possibly damaging rare variants detected by NeuroX array in affected individuals. Analysis of family members on a genome-wide DNA methylation chip revealed that the DNA methylation age of the triplets was 6-10 years younger than chronological age, while it was 9 years older in the offspring with early-onset Alzheimer's disease, suggesting accelerated ageing.

Cerebrovascular Resistance in Healthy Aging and Mild Cognitive Impairment

Measures of cerebrovascular reactivity (CVR) are used to judge the health of the brain vasculature. In this study, we report the use of several different analyses of blood oxygen dependent (BOLD) fMRI responses to CO₂ to provide a number of metrics of CVR based on the sigmoidal resistance response to CO₂. To assess possible differences in these metrics with age, we compiled atlases reflecting voxel-wise means and standard deviations for four different age ranges and for a group of patients with mild cognitive impairment (MCI) and compared them. Sixty-seven subjects were recruited for this study and scanned at 3T field strength. Of those, 51 healthy control volunteers between the ages of 18–83 were recruited, and 16 (MCI) subjects between the ages of 61–83 were recruited. Testing was carried out using an automated computer-controlled gas blender to induce hypercapnia in a step and ramp paradigm while monitoring end-tidal partial pressures of CO₂. Surprisingly, some resistance sigmoid parameters in the oldest control group were increased compared to the youngest control group. Resistance amplitude maps showed increases in clusters within the temporal cortex, thalamus, corpus callosum and brainstem, and resistance reserve maps showed increases in clusters within the cingulate cortex, frontal gyrus, and corpus callosum. These findings suggest that some aspects of vascular reactivity in parts of the brain are initially maintained with age but then may increase in later years. We found significant reductions in all resistance sigmoid parameters (amplitude, reserve, sensitivity, midpoint, and range) when comparing MCI patients to controls. Additionally, in controls and in MCI patients, amplitude, range, reserve, and sensitivity in white matter (WM) was significantly reduced compared to gray matter (GM). WM midpoints were significantly above those of GM. Our general conclusion is that vascular regulation in terms of cerebral blood flow (CBF) responsiveness to CO₂ is not significantly affected by age, but is reduced in MCI. These changes in cerebrovascular regulation demonstrate the value of resistance metrics for mapping areas of dysregulated blood flow in individuals with MCI. They may also be of value in the investigation of patients with vascular risk factors at risk for developing vascular dementia.

Mobile Technology for Cognitive Assessment of Older Adults: A Scoping Review

BACKGROUND AND OBJECTIVES

The number of people diagnosed with dementia is rising appreciably as the population ages. In an effort to improve outcomes, many have called for facilitating early detection of cognitive decline. Increased use of mobile technology by older adults provides the opportunity to deliver convenient, cost-effective assessments for earlier detection of cognitive impairment. This article presents a review of the literature on how mobile platforms-smartphones and tablets-are being used for cognitive assessment of older adults along with benefits and opportunities associated with using mobile platforms for cognitive assessment.

RESEARCH DESIGN AND METHODS

We searched MEDLINE, Web of Science, PsycInfo, CINAHL, EMBASE, and Cochrane Central Register of Controlled Trials in October 2018. This search returned 7,024 articles. After removing 1,464 duplicates, we screened titles and abstracts then screened full-text for those articles meeting inclusion and exclusion criteria.

RESULTS

Twenty-nine articles met our inclusion criteria and were categorized into 3 groups as follows: (a) mobile versions of existing article or computerized neuropsychological tests; (b) new cognitive tests developed specifically for mobile platforms; and (c) the use of new types of data for cognitive assessment. This scoping review confirms the considerable potential of mobile assessment.

DISCUSSION AND IMPLICATIONS

Mobile technologies facilitate repeated and continuous assessment and support unobtrusive collection of auxiliary behavioral markers of cognitive impairment, thus allowing users to view trends and detect acute changes that have traditionally been difficult to identify. Opportunities include using new mobile sensors and wearable devices, improving reliability and validity of mobile assessments, determining appropriate clinical use of mobile assessment information, and incorporating person-centered assessment principles and digital phenotyping.

Correction to: The Toronto cognitive assessment (TorCA): normative data and validation to detect amnestic mild cognitive impairment

Upon publication of this article [1], it was brought to our attention that one of the 303 participants in the normative study should have been deleted from the database.