•1st place in International Challenge for Automated Prediction of MCI from MRI Data.•Multi-class classification of normal control, MCI, converting MCI, and Alzheimer’s disease.•Morphometric measures ...from 3D T1 brain MRI images have been analysed (ADNI1 cohort).•A Random Forest Feature Selection, Fusion and Ensemble Strategy was applied to classification and prediction of AD.•Accuracy and robustness have been assessed in a blind dataset.
In the era of computer-assisted diagnostic tools for various brain diseases, Alzheimer’s disease (AD) covers a large percentage of neuroimaging research, with the main scope being its use in daily practice. However, there has been no study attempting to simultaneously discriminate among Healthy Controls (HC), early mild cognitive impairment (MCI), late MCI (cMCI) and stable AD, using features derived from a single modality, namely MRI.
Based on preprocessed MRI images from the organizers of a neuroimaging challenge,33The preprocessing of the T1-weighted Magnetic Resonance Images (MRI) was conducted by the organizers of the competition; information can be found here: https://inclass.kaggle.com/c/mci-prediction we attempted to quantify the prediction accuracy of multiple morphological MRI features to simultaneously discriminate among HC, MCI, cMCI and AD. We explored the efficacy of a novel scheme that includes multiple feature selections via Random Forest from subsets of the whole set of features (e.g. whole set, left/right hemisphere etc.), Random Forest classification using a fusion approach and ensemble classification via majority voting.
From the ADNI database, 60 HC, 60 MCI, 60 cMCI and 60 CE were used as a training set with known labels. An extra dataset of 160 subjects (HC: 40, MCI: 40, cMCI: 40 and AD: 40) was used as an external blind validation dataset to evaluate the proposed machine learning scheme.
In the second blind dataset, we succeeded in a four-class classification of 61.9% by combining MRI-based features with a Random Forest-based Ensemble Strategy. We achieved the best classification accuracy of all teams that participated in this neuroimaging competition.
The results demonstrate the effectiveness of the proposed scheme to simultaneously discriminate among four groups using morphological MRI features for the very first time in the literature.
Hence, the proposed machine learning scheme can be used to define single and multi-modal biomarkers for AD.
People with severe motor impairment face many challenges in communication and control of the environment, whilst survivors from neurological disorders have increased demand for advanced, adaptive and ...personalized rehabilitation. The last decades many studies have underlined the importance of brain-computer interfaces (BCIs) with great contributions ranging from communication restoration to motor rehabilitation. In this work we review BCI research that focuses on noninvasive, electroencephalography (EEG)-based BCI systems for people with motor impairment as far as communication and rehabilitation aspects are concerned. More specifically we overview milestone approaches that are primarily intended to help severely paralyzed and/or locked-in state patients by using three different BCI modalities, i.e., slow cortical potentials, sensorimotor rhythms and P300 potentials as operational mechanisms. In addition, we review BCI systems with special emphasis on restoration of motor function for patients with spinal cord injury and chronic stroke. Finally, we summarize how EEG-based BCI systems have contributed to communication and rehabilitation of motor impaired people, stress out advantages and limitations and discuss the challenges that these systems should address in the future.
Background
There is a pressing need to clarify whether vascular risk factors (VRFs) are related to the heterogeneous cognitive performance found in mild cognitive impairment (MCI) and whether the ...number of VRFs relates to financial capacity impairment in patients with amnestic MCI (aMCI).
Methods
A total of 112 participants were divided into three groups: patients with single‐domain aMCI, patients with multiple‐domain aMCI, and healthy controls (HCs), while taking into consideration whether participants had a diagnosis of one VRF or disease, or more than one VRF or disease. Patients with aMCI with VRFs (one and more than one VRF) and HCs did not differ significantly in age, education, and sex. Mini‐Mental State Examination, 15‐item Geriatric Depression Scale, and Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS) were administered to all groups.
Results
Diagnosis (P <0.001) and VRFs (P = 0.006) showed significant main effects on LCPLTAS but no interaction (P = 0.654). Patients with aMCI with high vascular burden were more frequently of the multiple‐domain subtype, whereas patients with no vascular burden were more frequently of the single‐domain subtype. A larger vascular burden is correlated with lower LCPLTAS scores.
Discussion
Vascular burden plays an important role in the heterogeneity of aMCI by impairing financial capacity.
Introduction
This study investigated the diagnostic and disease‐monitoring potential of plasma biomarkers in mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia and cognitively ...unimpaired (CU) individuals.
Methods
Plasma was analyzed using Simoa assays from 99 CU, 107 MCI, and 103 AD dementia participants.
Results
Phosphorylated‐tau181 (P‐tau181), neurofilament light, amyloid‐β (Aβ42/40), Total‐tau and Glial fibrillary acidic protein were altered in AD dementia but P‐tau181 significantly outperformed all biomarkers in differentiating AD dementia from CU (area under the curve AUC = 0.91). P‐tau181 was increased in MCI converters compared to non‐converters. Higher P‐tau181 was associated with steeper cognitive decline and gray matter loss in temporal regions. Longitudinal change of P‐tau181 was strongly associated with gray matter loss in the full sample and with Aβ measures in CU individuals.
Discussion
P‐tau181 detected AD at MCI and dementia stages and was strongly associated with cognitive decline and gray matter loss. These findings highlight the potential value of plasma P‐tau181 as a non‐invasive and cost‐effective diagnostic and prognostic biomarker in AD.
Research in the last decade has focused on assessing financial capacity and incapacity mainly in old age, but new research has turned to address the question of how financial incapacity can be ...predicted by cognitive factors. The aim of this study was to identify which cognitive domains predict financial capacity and the relevant cognitive skills of patients with mild Alzheimer's disease (AD) in order to assist neurologists in functional assessment and further patient referral. In this study, 109 patients diagnosed with mild AD were examined with a number of neuropsychological tests: Mini-Mental State Examination (MMSE), Functional Rating Scale for Symptoms of Dementia (FRSSD), Functional Cognitive Assessment Scale (FUCAS), Trail Making Test (TMT)-Part B, Rey-Osterrieth Complex Figure Test (ROCFT)-copy condition and delayed recall condition, Rey Auditory Verbal Learning Test (RAVLT), Boston Naming Test, Rivermead Behavioural Memory Test (RBMT), digit span forward and backward, WAIS-R digit symbol substitution test, Neuropsychiatric Inventory (NPI), Geriatric Depression Scale (GDS-15), and the Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS). LCPLTAS total score and relevant subdomains were best predicted only by the score of one item coming from MMSE: subtraction of serial sevens. This is the only measure of arithmetic testing in use for the Greek geriatric population. Financial capacity is severely impaired in the group of mild AD patients. In order to prevent financial exploitation cases, neurologists, neuropsychologists, psychiatrists, and geriatrists should pay close attention to the information from the relevant arithmetic question of MMSE, as it is one of the most widely administered screening tests in clinical settings.
•Current financial capacity assessment doesn't address the influence of NA on the performance of elderly.•State NA has a noticeable impact on financial capacity performance in nondepressed elders.•An ...ideal financial capacity assessment would examine not only of depression, but also NA.
Although research supports that elevated depressive symptoms are associated with deficits in financial capacity performance, so far positive affect (PA) and negative affect (NA) are not investigated in relation to financial capacity. This study examined relationships between state affect and cognitive impairment with an emphasis on financial capacity in nondepressed older individuals.
134 elders without a past or current formal medical diagnosis underwent a detailed neuropsychological assessment, including Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS-15), Positive Affect and Negative Affect Schedule (PANAS), and Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS).
: Findings support that a high total NA score was associated with lower LCPLTAS total score when depression does not co-exist, resembling the performance of patients with aMCI.
Limitations include the relatively small sample size.
Current financial capacity assessment options do not address the influence of state affect on the performance of elders. A special care for individuals with high NA, without depression should be considered, as NA negatively impacts financial capacity in healthy elders. Clinicians should consider the evaluation of PA and NA during the neuropsychological assessment of financial capacity in elders as affect is related in a pivotal way with financial performance.
•Network disorganization in people with Subjective Cognitive Decline (SCD) was found in the majority of the reported studies.•Brain connectome in SCD is disrupted in a similar way as in mild ...cognitive impairment compared to Healthy Controls.•Small-world and rich-club were preserved in SCDs while aberrant local connections were observed.
We performed a systematic literature review on Subjective Cognitive Decline (SCD) in order to examine whether the resemblance of brain connectome and functional connectivity (FC) alterations in SCD with respect to MCI, AD and HC can help us draw conclusions on the progression of SCD to more advanced stages of dementia.
We searched for studies that used any neuroimaging tool to investigate potential differences/similarities of brain connectome in SCD with respect to HC, MCI, and AD.
Sixteen studies were finally included in the review. Apparent FC connections and disruptions were observed in the white matter, default mode and gray matter networks in SCD with regards to HC, MCI, and AD. Interestingly, more apparent connections in SCD were located over the posterior regions, while an increase of FC over anterior regions was observed as the disease progressed.
Elders with SCD display a significant disruption of the brain network, which in most of the cases is worse than HC across multiple network parameters.
The present review provides comprehensive and balanced coverage of a timely target research activity around SCD with the intention to identify similarities/differences across patient groups on the basis of brain connectome properties.
Dementia is a multifaceted disorder that impairs cognitive functions, such as memory, language, and executive functions necessary to plan, organize, and prioritize tasks required for goal-directed ...behaviors. In most cases, individuals with dementia experience difficulties interacting with physical and social environments. The purpose of this study was to establish ecological validity and initial construct validity of a fire evacuation Virtual Reality Day-Out Task (VR-DOT) environment based on performance profiles as a screening tool for early dementia.
The objectives were (1) to examine the relationships among the performances of 3 groups of participants in the VR-DOT and traditional neuropsychological tests employed to assess executive functions, and (2) to compare the performance of participants with mild Alzheimer's-type dementia (AD) to those with amnestic single-domain mild cognitive impairment (MCI) and healthy controls in the VR-DOT and traditional neuropsychological tests used to assess executive functions. We hypothesized that the 2 cognitively impaired groups would have distinct performance profiles and show significantly impaired independent functioning in ADL compared to the healthy controls.
The study population included 3 groups: 72 healthy control elderly participants, 65 amnestic MCI participants, and 68 mild AD participants. A natural user interface framework based on a fire evacuation VR-DOT environment was used for assessing physical and cognitive abilities of seniors over 3 years. VR-DOT focuses on the subtle errors and patterns in performing everyday activities and has the advantage of not depending on a subjective rating of an individual person. We further assessed functional capacity by both neuropsychological tests (including measures of attention, memory, working memory, executive functions, language, and depression). We also evaluated performance in finger tapping, grip strength, stride length, gait speed, and chair stands separately and while performing VR-DOTs in order to correlate performance in these measures with VR-DOTs because performance while navigating a virtual environment is a valid and reliable indicator of cognitive decline in elderly persons.
The mild AD group was more impaired than the amnestic MCI group, and both were more impaired than healthy controls. The novel VR-DOT functional index correlated strongly with standard cognitive and functional measurements, such as mini-mental state examination (MMSE; rho=0.26, P=.01) and Bristol Activities of Daily Living (ADL) scale scores (rho=0.32, P=.001).
Functional impairment is a defining characteristic of predementia and is partly dependent on the degree of cognitive impairment. The novel virtual reality measures of functional ability seem more sensitive to functional impairment than qualitative measures in predementia, thus accurately differentiating from healthy controls. We conclude that VR-DOT is an effective tool for discriminating predementia and mild AD from controls by detecting differences in terms of errors, omissions, and perseverations while measuring ADL functional ability.
Background/Objective:
This study examined for the first time in Greece, the estate planning and advance care planning (ACP) of healthy older adults and older patients diagnosed with different types ...of neurocognitive disorders for the presence of a valid will, a durable power of attorney for healthcare, and a living will, while the associations between general cognition, education, depression, actual financial capacity, and demographic and socioeconomic characteristics were examined.
Methods:
A total of 543 participants were examined with neuropsychological tests including Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS). Along with the neuropsychological examination, all participants responded to relevant ACP questions.
Results:
Surprisingly, the majority of the participants regardless of their diagnostic group did not have a valid will, had not assigned a durable power of attorney for healthcare, and had not a written living will. Logistic regression revealed that biological sex, age, education, marital status, diagnostic group, MMSE, GDS, and actual financial capacity as measured with LCPLTAS did not predict the existence of a valid will, durable power of attorney, and written living will.
Conclusions:
A diagnosis of AD is not associated with more engagement in ACP as supported by research in USA. Concerns are raised about possible exploitation and abuse of older patients.
PDF
