The Validity and Reliability of the Mini-Mental State Examination-2 for Detecting Vascular Mild Cognitive Impairment and Vascular Dementia in a Korean Population.

Background: This study aimed to evaluate the validity and reliability of the Mini-Mental State Examination, 2nd Edition (MMSE-2), as a cognitive screening tool for patients with vascular mild cognitive impairment (VaMCI) and vascular dementia (VD) in a Korean population. Specifically, we investigated whether the MMSE-2 effectively detects early cognitive changes associated with vascular cognitive impairment (VCI) that might be overlooked by the original Mini-Mental State Examination (MMSE).

Methods: A total of 66 patients with VaMCI, 46 patients with VD, and 75 cognitively healthy older adults participated in this study.

A Normative Study of the Trail Making Test-Black and White in the Korean Population.

Objective: Although the Trail Making Test (TMT) is widely used to identify cognitive dysfunction, it has limited utility in cross-cultural contexts due to the use of the English alphabet in a subset of the test. The TMT-Black and White (TMT-B&W) is a newly developed version of the TMT that uses only black and white circles to overcome performance biases among non-English-speaking and illiterate older individuals. The objective of this study was to provide initial normative data for the TMT-B&W from the Korean population and investigate the influence of age, sex, and education level on the time taken to complete the test.

Effect of Post-Weld Heat Treatment on Residual Stress and Fatigue Crack Propagation Behavior in Linear Friction Welded Ti-6Al-4V Alloy.

In this study, the effects of post-weld heat treatment (PWHT) on residual stress distribution and fatigue crack propagation (FCP) behavior in linear friction welded (LFW) Ti-6Al-4V joints were investigated. Microstructural evolution in the weld center zone (WCZ), thermomechanically affected zone (TMAZ), heat-affected zone (HAZ), and base metal (BM) was characterized using scanning electron microscropy (SEM) and electron backscatter diffraction (EBSD). Mechanical properties were evaluated via Vickers hardness testing and digital image correlation (DIC)-based tensile testing.

Voxel-Based Morphometric Analysis of the Mini-Mental State Examination and the Mini-Mental State Examination-2 in Patients With Mild Cognitive Impairment and Alzheimer's Disease in Korea.

Background: This study investigated the association between the Mini-Mental State Examination-2 (MMSE-2) and the Korean version of the Mini-Mental State Examination (K-MMSE) scores with global cortical gray matter volume changes in healthy older adults, patients with mild cognitive impairment (MCI), and Alzheimer's Disease (AD) in Korea. Using voxel-based morphometry analysis of structural magnetic resonance imaging (MRI), we explored how these correlations evolve with the progression of cognitive impairment. Additionally, we identified brain regions linked to the newly added components of MMSE-2, such as story memory and processing speed.

Use of the Clock Drawing Test and the Rey-Osterrieth Complex Figure Test-copy with convolutional neural networks to predict cognitive impairment.

Background: The Clock Drawing Test (CDT) and Rey-Osterrieth Complex Figure Test (RCFT) are widely used as a part of neuropsychological test batteries to assess cognitive function. Our objective was to confirm the prediction accuracies of the RCFT-copy and CDT for cognitive impairment (CI) using convolutional neural network algorithms as a screening tool.

Methods: The CDT and RCFT-copy data were obtained from patients aged 60-80 years who had more than 6 years of education.

Coping with Dementia in the Middle of the COVID-19 Pandemic.

Multiple neurological complications have been associated with the coronavirus disease-19 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2. This is a narrative review to gather information on all aspects of COVID-19 in elderly patients with cognitive impairment. First, the following three mechanisms have been proposed to underlie the neurological complications associated with COVID-19: 1) direct invasion, 2) immune and inflammatory reaction, and 3) hypoxic brain damage by COVID-19.

Predictors of pre-operative cognitive impairment in meningioma patients over 60 years old.

Background: The aim of this study was to assess the cognitive function of patients over 60 years old with meningioma using a domain-specific neuropsychological test and to investigate the relevant factors affecting pre-operative cognitive decline in different subdomains.

Methods: We retrospectively investigated 46 intracranial meningioma patients between the ages of 60 and 85 years. All patients underwent brain MRI and neuropsychological test.

Prediction of cognitive impairment via deep learning trained with multi-center neuropsychological test data.

Background: Neuropsychological tests (NPTs) are important tools for informing diagnoses of cognitive impairment (CI). However, interpreting NPTs requires specialists and is thus time-consuming. To streamline the application of NPTs in clinical settings, we developed and evaluated the accuracy of a machine learning algorithm using multi-center NPT data.

Re-standardization of the Korean-Instrumental Activities of Daily Living (K-IADL): Clinical Usefulness for Various Neurodegenerative Diseases.

Background And Purpose: Evaluating instrumental activities of daily living (IADL) is an important part of procedure to diagnose dementia. The Korean-Instrumental Activities of Daily Living (K-IADL) has been used extensively in Korea. However, its cut-off score has not been reformulated since 2002.

The usefulness of visual rating of posterior atrophy in predicting rapid cognitive decline in Alzheimer disease: A preliminary study.

Background: Approximately 10% to 30% of Alzheimer disease (AD) patients progress rapidly in severity and become more dependent on caregivers. Although several studies have investigated whether imaging biomarkers such as medial temporal atrophy (MTA) and posterior atrophy (PA) are useful for predicting the rapid progression of AD, their results have been inconsistent.

Objective: The study aims to investigate the association of visually rated MTA and PA with rapid disease progression in AD.

Driving Cessation and Cognitive Dysfunction in Patients with Mild Cognitive Impairment.

Although driving by adults with cognitive impairment is an important public health concern, little is known about the indicators of driving cessation in patients with mild cognitive impairment (MCI). We aimed to investigate the prevalence of driving cessation in patients with MCI and the predictive value of cognitive performances for driving cessation. Patients with MCI were recruited in the Seoul National University Bundang Hospital; they met following inclusion criteria.

Multimodal Assessment of Neural Substrates in Computerized Cognitive Training: A Preliminary Study.

Background And Purpose: Several studies have validated the clinical efficacy of computerized cognitive training applications. However, few studies have investigated the neural substrates of these training applications using simultaneous multimodal neuroimaging modalities. We aimed to determine the effectiveness of computerized cognitive training and corresponding neural substrates through a multimodal approach.

A Comparison of Five Types of Trail Making Test in Korean Elderly.

Background And Purpose: Previously developed Korean versions of the Trail Making Test (TMT) that replaced the English in part B, has been unsuccessful in Korea. The current study identifies the type of TMT tasks from the among multiple TMT versions, which practically and accurately detects the stage of cognitive decline.

Methods: We applied five TMT versions, which include the original TMT, TMT-Korean letter (TMT-KL), TMT-Korean consonant (TMT-KC), TMT-black and white (TMT-B&W), and TMT-square and circle (TMT-S&C).

The Validity and Reliability of the Mini-Mental State Examination-2 for Detecting Mild Cognitive Impairment and Alzheimer's Disease in a Korean Population.

Objective: To examine the validity and reliability of the MMSE-2 for assessing patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) in a Korean population. Specifically, the usefulness of the MMSE-2 as a screening measure for detecting early cognitive change, which has not been detectable through the MMSE, was examined.

Methods: Two-hundred and twenty-six patients with MCI, 97 patients with AD, and 91 healthy older adults were recruited.

Visual Rating of Posterior Atrophy as a Marker of Progression to Dementia in Mild Cognitive Impairment Patients.

Background: Although medial temporal atrophy (MTA) is a useful imaging marker of the progression to dementia in mild cognitive impairment (MCI), substantial numbers of MCI patients without MTA still progress to dementia.

Objective: We investigated whether visual ratings of posterior atrophy (PA) on magnetic resonance imaging show independent predictive value for the progression to dementia in MCI patients.

Methods: This was a retrospective cohort study of elderly patients who visited Seoul National University Bundang Hospital between 2004 and 2012.

Abstract Word Definition in Patients with Amnestic Mild Cognitive Impairment.

The aims of this study were to investigate concrete and abstract word definition ability (1) between patients with amnestic mild cognitive impairment (aMCI) and normal adults and (2) between the aMCI subtypes (i.e., amnestic single-domain MCI and amnestic multidomain MCI; asMCI and amMCI) and normal controls.

Executive function as a strong predictor of recovery from disability in patients with acute stroke: a preliminary study.

Background: Cognitive impairment impedes stroke rehabilitation. However, it is unclear whether cognitive impairment of specific domains or the degree of severity is more critical to functional recovery in patients with poststroke disability.

Methods: We identified 182 patients who were disabled at 3 months after acute stroke, as defined by a modified Rankin Scale score of 2-5.

A comprehensive visual rating scale of brain magnetic resonance imaging: application in elderly subjects with Alzheimer's disease, mild cognitive impairment, and normal cognition.

Background: Brain magnetic resonance imaging (MRI) shows cerebral structural changes. However, a unified comprehensive visual rating scale (CVRS) has seldom been studied. Thus, we combined brain atrophy and small vessel disease scales and used an MRI template as a CVRS.

Cortical hubs and subcortical cholinergic pathways as neural substrates of poststroke dementia.

Background And Purpose: A role of neural networks in the development of poststroke dementia has not been clearly established. We hypothesized that stroke-mediated disruption of subcortical cholinergic pathway or large-scale neural networks contributes to poststroke dementia.

Methods: A matched case-control study was conducted in a predetermined cohort with acute ischemic stroke.

Alternative type of the trail making test in nonnative English-speakers: the trail making test-black & white.

Objective: The Trail Making Test (TMT) has its limitations when applied to Eastern cultures due to its reliance on the alphabet. We looked for an alternative tool that is reliable and distinguishable like the TMT and devised the Trail Making Test Black & White (TMT-B&W) as a new variant. This study identifies the applicability of the TMT-B&W as a useful neuropsychological tool and determines whether the TMT-B&W could play an equivalent role as the TMT.

Comparison between the story recall test and the word-list learning test in Korean patients with mild cognitive impairment and early stage of Alzheimer's disease.

Among verbal memory tests, two that are commonly used to measure the ability of verbal memory function in cognitive impairment are story recall tests and word-list learning tests. However, research is limited regarding which test might be more sensitive in discriminating between normal cognitive aging and patients with Alzheimer's disease (AD) in the Korean population. The purpose of the current study was to compare the word-list learning test (Seoul Verbal Learning Test; SVLT) and the story recall test (Korean Story Recall Test; KSRT) to determine which test is more sensitive in discriminating between individuals with normal cognitive aging and patients with mild cognitive impairment (MCI) and early stage of AD in Korea.

Line quadrisection errors in patients with hemispatial neglect.

Patients with left unilateral neglect misbisect lines toward the right. To discriminate between contralesional unawareness and ipsilesional hyperattention hypotheses for this ipsilesional bias, we performed the line quadrisection test on 18 patients with and 25 without neglect, and 24 normal controls. Overall the patients with neglect were unbiased when performing the left quadrisection task, but erred rightward on the right quadrisection task.

Non-invasive cortical stimulation improves post-stroke attention decline.

Purpose: Attention decline after stroke is common and hampers the rehabilitation process, and non-invasive transcranial direct current stimulation (tDCS) has the potential to elicit behavioral changes by modulating cortical excitability. The authors tested the hypothesis that a single session of non-invasive cortical stimulation with excitatory anodal tDCS applied to the left dorsolateral prefrontal cortex (DLPFC) can improve attention in stroke patients.

Methods: Ten patients with post-stroke cognitive decline (MMSE 25) and 10 age-matched healthy controls participated in this double blind, sham-controlled, crossover study involving the administration of real (2 mA for 20 min) or sham stimulation (2 mA for 1 min) to the left DLPFC.