Function In Mild Cognitive Impairment Research Articles

Spiral Tracing in Alzheimer’s Disease: Less Precise but not Slower

AbstractBackgroundIn the search for novel Alzheimer’s disease (AD) biomarkers, motor functional outcome measures are potential candidates, as motor impairments can precede cognitive dysfunction. Whereas most motor behavioral research in Mild Cognitive Impairment (MCI) and AD has focused on gait function, fine motor skill is affected as well. Here, we use a digitized version of the Archimedes spiral test to assess a variety of speed and accuracy metrics of fine motor function in MCI and AD compared to cognitively normal (CN) individuals.Method46 CN, 23 MCI, and 17 AD participants traced an Archimedes spiral 3 times using a digital pen tablet. Spiral outcome measures included: path length, movement time, tracing speed (average and variance), radial distance (i.e., total deviation from the spiral template; average and variance), number of template crossings, and return movements.ResultLinear regression analysis adjusted for age and sex showed that those with AD had significantly larger radial distance than CN (p = .0056, eta^2 = .096). No other significant group differences were observed (all p>0.14, all eta^2<.028).ConclusionResults indicate that individuals with AD are less precise when tracing an Archimedes spiral, despite adequate movement speed and steadiness. These results support a wider examination of fine motor dysfunction in AD as an inexpensive and easily collectable biomarker in AD.

Go4cognition: Combined Physiological and Cognitive Intervention in Mild Cognitive Impairment

While cognitive interventions in mild cognitive impairment (MCI) show positive effects on cognitive performance, physical activity appear to slow down cognitive decline, suggesting a relationship between both factors. However, previous combined programs that have shown significant improvement in cognitive function in MCI have typically trained cognition and physical functioning separately. This project aimed at evaluating two group interventions combining the stimulation of physical and cognitive domains in individuals with MCI: Simultaneous stimulation of physical and cognitive skills in comparison to a standardized training, which stimulates cognitive and physical functions separately. The study was designed as a randomized controlled trial. The first group was trained on the SpeedCourt® system while the second group completed the standardized Fitfor100 program. Training was completed by a total of 39 subjects with diagnosed MCI as determined by the CERAD (SpeedCourt®: 24 subjects, Fitfor100:15 individuals). There were significant improvements of physical factors (e.g., hand strength and balance) in both groups. Improvement in the CERAD total score allowed for a post interventional classification of all participants into non-MCI and MCI. This effect persisted over a period of three months. Both forms of intervention were found to be effective in improving various cognitive functions which persisted for a period of three months. Both evaluated non-pharmacological, multicomponent interventions, which combined physical and cognitive training in a social setting showed improvement of cognitive functions leading to a persistent classification of former MCI patients in non-MCI patients.

Effect of hearing loss on cognitive function in patients with mild cognitive impairment: A prospective, randomized, and controlled study.

BackgroundHearing loss (HL) may increase the risk of cognitive decline in the elderly. However, the randomized controlled study on the effect of HL on cognitive function in mild cognitive impairment (MCI) is very limited.MethodsFrom 1 November 2020 to 30 March 2022, 1,987 individuals aged 55–65 years were randomly divided into the MCI with hearing impairment (MCI-HI), MCI without HI (MCI-nHI), and no MCI (nMCI) groups by stratified sampling, with 30 participants in each group. The Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), the pure tone audiometry (PTA), and the auditory brainstem response (ABR) were measured at baseline and a follow-up 12 months later. The trial protocol was registered with ClinicalTrials.gov with the registration number NCT05336942.ResultsAmong the 90 participants, the average age was 60.41 ± 6.48 years. In the MCI-HI group at baseline, the PTA score of both the ears was negatively correlated with the naming and memory score (p < 0.05), and the PTA score of both the ears was negatively correlated with the MoCA and abstraction score at the 12-month follow-up (p < 0.05). However, there were no significant differences among the PTA, the ABR, the MMSE, and the MoCA scores in the MCI-nHI and nMCI groups (p > 0.05). Regression analysis showed that the PTA score of the right ear at baseline was an important factor associated with the MoCA, visuospatial/executive, naming, and abstraction scores at the 12-month follow-up (β = −0.776 to −0.422, p < 0.05).ConclusionHL was significantly negatively associated with cognitive function only in patients with MCI with hearing impairment (HI), and the PTA of the right ear may be a predictor of cognitive decline after 1 year in patients with MCI with HI. This information may help primary healthcare clinicians to prevent MCI by screening and intervening in care for elderly patients with HL.

Relations of neuropsychiatric symptoms with disease stage, sex, and daily function in mild cognitive impairment and dementia due to Alzheimer's disease: A cross-sectional study

ObjectiveTo reveal the relations between neuropsychiatric symptoms (NPS), stages of cognitive impairment, sex, and daily function in patients with mild cognitive impairment (MCI) and dementia due to Alzheimer's disease (AD). MethodsA cross-sectional study was conducted from 2014 to 2021 on 1154 patients. Cognitive function, disease severity, NPS, and daily function were evaluated by Mini-mental State Examination, Clinical Dementia Rating Scale, Neuropsychiatric Inventory, and Activities of Daily Living (ADL) respectively. Multivariate logistic regression and linear regression were used to explore the correlations between NPS, disease stage, sex and ADL. ResultsAffective disturbance displayed the highest prevalence from MCI (52.7%) to severe dementia due to AD (98.2%). Multivariate logistic regression revealed that aberrant motor behavior displayed higher prevalence between groups from MCI to severe dementia due to AD (OR = 4.710, P < 0.001; OR = 3.141, P < 0.001; OR = 2.722, P = 0.002, respectively). In patients with dementia due to AD, hallucination and depression were more prevalent in female (OR = 1.730, P = 0.001; OR = 2.376, P < 0.001, respectively) while male presented higher prevalence in apathy (OR = 0.608, P = 0.002). Linear regression analysis showed that delusion and sleep disturbance were significantly associated with basic ADL across all dementia due to AD stages (delusion: mild: β = 0.113, P = 0.015; moderate: β = 0.159, P = 0.019; severe: β = 0.317, P = 0.018; sleep disturbance: mild: β = 0.164, P < 0.001; moderate: β = 0.167, P = 0.013; severe: β = 0.308, P = 0.025) while anxiety was correlated with instrumental ADL from MCI to moderate dementia due to AD (MCI: β = 0.119, P = 0.006; mild: β = 0.149, P < 0.001; moderate: β = 0.130, P = 0.042). ConclusionDifferent subitems of NPS are strongly correlated with sex, stage of cognitive impairment, and ADL.

A novel Arabic tool of cognitive assessment in patients with mild cognitive impairment

IntroductionMild cognitive impairment is one of the commonly reported disorders nowadays in old age individuals,it might represent the prodroma of definite dementia.There is a novel Arabic tool now which could help in the evaluation of cognitive functions in these patients.Objectives1-To study the cognitive functions in mild cognitive impairment by a novel Thinc-it tool (Arabic version) 2-To compare between Mini Mental Status Examination ( Standard test) and the novel Thinc-it battery ( Arabic version ) in detection of cognitive dysfunctions in these patients.Methods1-The Mini Mental State Examination (MMSE) is a tool that can be used to systematically and thoroughly assess mental status. It is an 11-question measure that tests five areas of cognitive function: orientation, registration, attention and calculation, recall, and language. The maximum score is 30. A score of 23 or lower is indicative of cognitive impairment. The MMSE takes only 5-10 minutes to administer and is therefore practical to use repeatedly and routinely 2-Thinc-it THINC-it® is a screening tool designed to measure cognition and provides important data for an overall evaluation of whether cognitive functioning is impaired,it includes the folloowing tests: 1.PDQ-5D Subjective Questionnaire2.“Spotter” – CRT game3.“Symbol Check” – Nback game4.“CodeBreaker” – DSST game5.Trails – TMT gameResultsThe results of Thinc-it (Arabic version) is statistically correlated to the mean score of Mini Mental state Examination,this means this Arabic version is a valid novel tool for assessment of Cognitive dysfunctions .ConclusionsArabic version of Thinc-it can be used in cognitive evaluationDisclosureNo significant relationships.

Decision-Making Profiles and Their Associations with Cognitive Performance in Mild Cognitive Impairment.

It is crucial for older adults, especially those with mild cognitive impairment (MCI), to make profitable decisions routinely. However, the results regarding decision-making (DM) remain inconsistent. The present study assessed DM profiles under uncertainty conditions in individuals with MCI and their associations with multi-domain cognitive performance. Fifty-three patients with MCI and forty-two age-, gender-, and education level-matched healthy controls (HCs) were administered a comprehensive neuropsychological battery test. The Iowa Gambling Task (IGT) and Game of Dice Task (GDT) were used to assess DM competence in conditions involving ambiguity and risk, respectively. In addition, Spearman's correlations were used to examine relationships between GDT and multi-domain cognitive performance. The final capital (FC) and frequency of utilization of negative feedback (FUNF) and positive feedback (FUPF) in the GDT were lower in MCI patients than in HCs. In addition, the number of shifts between safe and risky alternatives was significantly different across groups. However, IGT performance was comparable across groups. In the MCI patients, risky DM performance was associated with language, whereas in HCs was correlated with memory and executive functions. Besides, in MCI, performance on IGT was significantly correlated with social cognition. Individuals with mild cognitive impairment have difficulty utilizing feedback to make optimal decisions under risky situations. The association between decision-making performance and cognitive function is divergent regarding situational uncertainty and individuals' cognitive status. In mild cognitive impairment and normal aging, decision-making under ambiguity needs further investigation.

Can mild cognitive impairment and Alzheimer's disease be diagnosed by monitoring a miRNA triad in the blood?

Objectively diagnosing age‐related cognitive impairment (ACI), mild cognitive impairment (MCI), and early‐stage Alzheimer's disease (AD) is a difficult task, as most cognitive impairment is clinically established via questionnaires, history, and physical examinations. A recent study has suggested that monitoring a miRNA triad, miR‐181a‐5p, miR‐146a‐5p, and miR‐148a‐3p can identify ACI and its progression to MCI and AD (Islam et al., EMBO Mol Med. 13: e14997, 2021). This commentary deliberates findings from this article, such as elevated levels of the miRNA triad in the brain impairing neural plasticity and cognitive function, the efficiency of measuring the miRNA triad in the circulating blood diagnosing MCI and AD, and the promise for improving cognitive function in MCI and AD by inhibiting this miRNA triad. Additional studies required prior to employing this miRNA triad in clinical practice are also discussed.

Longitudinal Predictors of Informant-Rated Everyday Function in Mild Cognitive Impairment.

To examine predictors of informant-reported everyday functioning in mild cognitive impairment (MCI) and relations between everyday function and conversion to dementia. Informants of participants (n = 2614) with mild cognitive impairment (MCI) were administered the Functional Activities Questionnaire (FAQ). Changes in dimensions of functional ability as determined by an exploratory factor analysis (EFA) were examined over 3years and participant predictors of change were examined using multilevel modeling (MLM). The FAQ consisted of 3 factors, multistep, finance, and memory/orientation daily tasks. Impairment in memory/orientation tasks was significantly higher than impairment in multistep tasks. Worse functioning was associated with greater depression, worse memory, worse speed/EF, higher years of education and identifying as White. There was variability in some of these associations with different FAQ factors. Impairments in financial and memory/orientation daily tasks predicted follow-up conversion to dementia. Depression, speed/EF, and memory are consistently associated with domains of everyday functioning. Race, education, and age may be more variability associated with everyday functioning. Specific attention should be paid to subtle declines in the financial and memory/orientation domains as they may uniquely predict future dementia development. Depression may be a modifiable risk factor associated with functional impairment over time.

Examining heterogeneity in depression symptoms and associations with cognition and everyday function in MCI

ABSTRACT Introduction Although there is some evidence that different symptoms of depression have differential effects on cognition in older adults, these relationships remain understudied in older adults with mild cognitive impairment (MCI). Method Older adults (>50 years old) were classified as having MCI by Alzheimer’s Disease Research Centers (ADRCs). Exploratory factor analyses and factor mixture modeling were used to determine depression symptom classes. Classes were then compared across different domains of cognition (i.e., memory, attention, language, and executive function) and informant-rated everyday function. Results Analyses revealed six, distinct symptom classes (i.e., somatic symptoms, severely depressed, anhedonic symptoms, cognitive symptoms, minimally depressed, and low life satisfaction symptoms). Classes significantly varied on all measures of cognition and everyday function. In particular, the anhedonic class often showed the most substantial decline (on par with the severely depressed class), while the low life satisfaction class often showed the least (on par with the minimally depressed class). Conclusions To our knowledge, this is the first study to examine the relationship between depression symptom profiles and cognitive and everyday function in those with MCI. Our findings show that depression symptoms greatly differ in their associations with cognitive and everyday function. It may be beneficial for clinicians to specifically note if patients with MCI are reporting anhedonic and somatic symptoms of depression specifically.

Retention and impairment of neurocognitive functions in mild cognitive impairment and Alzheimer's disease with a comprehensive neuropsychological test.

AimMATRICS Consensus Cognitive Battery was developed by the National Institute of Mental Health to establish acceptance criteria for measuring cognitive changes in schizophrenia and can be used to assess cognitive functions in other psychiatric disorders. We used a Japanese version of MATRICS Consensus Cognitive Battery to explore the changes in multiple cognitive functions in patients with mild cognitive impairment and mild Alzheimer's disease.MethodsWe administered the Japanese version of MATRICS Consensus Cognitive Battery to 11 patients with mild cognitive impairment (MCI), 11 patients with Alzheimer's disease, and 27 healthy controls. All Japanese versions of MATRICS Consensus Cognitive Battery domain scores were converted to t‐scores using sample means and standard deviations and were compared for significant performance differences among healthy control, MCI, and mild Alzheimer's disease groups.ResultsCompared with healthy controls, patients with MCI and mild Alzheimer's disease demonstrated the same degree of impairment to processing speed, verbal learning, and visual learning. Reasoning and problem‐solving showed significant impairments only in mild Alzheimer's disease. Verbal and visual abilities in working memory showed different performances in the MCI and mild Alzheimer's disease groups, with the Alzheimer's disease group demonstrating significantly more deficits in these domains. No significant difference was found among the groups in attention/vigilance and social cognition.ConclusionsThe Japanese version of MATRICS Consensus Cognitive Battery can be used to elucidate the characteristics of cognitive dysfunction of normal aging, MCI, and mild dementia in clinical practice.

Functional Neural Correlates of Semantic Fluency Task Performance in Mild Cognitive Impairment and Alzheimer's Disease: An FDG-PET Study.

Total score (TS) of semantic verbal fluency test (SVFT) is generally used to interpret results, but it is ambiguous as to specific neural functions it reflects. Different SVFT strategy scores reflecting qualitative aspects are proposed to identify specific cognitive functions to overcome limitations of using the TS. Functional neural correlates of the TS as well as the other strategy scores in subjects with mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia using Fluorine-18-Fluorodeoxyglucose positron emission tomography (FDG-PET). Correlations between various SVFT scores (i.e., TS, mean cluster size, switching (SW), hard switching, cluster switching (CSW)) and cerebral glucose metabolism were explored using voxelwise whole-brain approach. Subgroup analyses were also performed based on the diagnosis and investigated the effects of disease severity on the associations. Significant positive correlation between TS and cerebral glucose metabolism was found in prefrontal, parietal, cingulate, temporal cortex, and subcortical regions. Significantly increased glucose metabolism associated with the SW were found in similar but smaller regions, mainly in the fronto-parieto-temporal regions. CSW was only correlated with the caudate. In the subgroup analysis conducted to assess different contribution of clinical severity, differential associations between the strategy scores and regional glucose metabolism were found. SW and CSW may reflect specific language and executive functions better than the TS. The SVFT is influenced by brain dysfunction due to the progression of AD, as demonstrated by the SW with larger involvement of temporal lobe for the AD, and CSW with significant association only for the MCI.

Association Between Body Mass Index and Cognitive Function in Mild Cognitive Impairment Regardless of APOE ε4 Status.

Background and PurposeIn this study we aimed to find the association between neuropsychological performance and body mass index (BMI) in patients with mild cognitive impairment (MCI). In addition, we investigated the effects of the apolipoprotein E (APOE) genotype in the relationship between the BMI and cognition in MCI.MethodsWe enrolled a cohort of 3,038 subjects with MCI aged 65–90 from the Clinical Research Center for Dementia of South Korea and a dementia cohort of the Ewha Womans University Mokdong Hospital. MCI patients were classified into three subgroups according to the Asian standard of BMI. We compared cognitive performances between groups by one-way analysis of variance. To investigate the effects of the APOE genotype, we used multivariate linear regression models after adjusting for possible confounders.ResultsEven though normal BMI groups were younger, had more females, and had less comorbidities, the higher BMI groups had better cognitive functions. Among subjects with APOE ε4 carriers, there was a positive relationship between the BMI and the memory task alone.ConclusionsOur findings suggested that higher BMI in patients with MCI were associated with better cognitive performance. The effects of the APOE ε4 genotype in the associations between BMI and cognition were distinguishing. Therefore, according to physical status, APOE ε4 genotype-specific strategies in the assessments and treatments may be necessary in elderly patients with MCI.

Association between long-term donepezil treatment and brain regional amyloid and tau burden among individuals with mild cognitive impairment assessed using 18 F-AV-45 and 18 F-AV-1451 PET.

This study aims to investigate the association between long-term donepezil treatment and brain neuropathological burden and cognitive function in mild cognitive impairment (MCI) patients. Preprocessed 18 F-AV-45 amyloid and 18 F-AV-1451 tau positron emission tomography (PET) images, magnetic resonance imaging images (MRIs), demographic information, and donepezil use status were downloaded from 255 MCI participants enrolled in the Alzheimer's Disease Neuroimaging Initiative database. Partial volume correction was applied to all PET images. Structural MRIs were used for PET spatial normalization. Regions of interest (ROIs) were defined in standard space, and standardized uptake value ratio (SUVR) images relative to the cerebellum were computed. Multiple linear regression with the least absolute shrinkage selector operator was performed to analyze the effect of long-term donepezil treatment on (a) the SUVR of each 18 F-AV-45 or 18 F-AV-1451 brain PET ROI after adjusting for age, sex, education, ApoE ε4 status, and AD-associated disease risk factors; and (b) cognitive performance after adjusting for age, sex education, ApoE ε4 status, AD-associated disease risk factors, and regional amyloid or tau burden. In adjusted models, long-term donepezil treatment was associated with greater amyloid load in the orbital frontal, superior frontal, parietal, posterior precuneus, posterior cingulate, lateral temporal, inferior temporal and fusiform regions, and tau burden in the posterior cingulate, entorhinal and parahippocampal gyrus. Long-term donepezil treatment was also associated with worse performance on the 13-item Alzheimer's Disease Assessment Scale-Cognitive subscale after adjusting for AD-related risk factors and regional brain amyloid or tau load. These results indicate that long-term donepezil treatment is associated with increased regional amyloid and tau burden and worse cognitive performance among individuals with MCI. Our study highlights the importance of using noninvasive and quantitative 18 F-AV-45 and 18 F-AV-1451 PET to elucidate the consequences of drug administration in AD studies.

Do fine motor impairments constitute a key feature of mild cognitive impairment? A systematic review and meta‐analysis

AbstractBackgroundTypical symptoms of mild cognitive impairment (MCI) include impairments in memory, executive function, and visuospatial skills. While impairments in these cognitive domains are highly apparent after MCI, impairments in motor domain are not so conspicuous. Converging evidence suggests that individuals with MCI demonstrate motor impairments in lower extremity such as reduced balance and impaired gait performance. However, the impact of MCI on upper extremity motor impairments is not well understood. In the current meta‐analysis, we examine whether fine motor impairments are a key feature of mild cognitive impairment.MethodWe performed a systematic search of electronic databases for articles published between 1990 and 2019. The meta‐analysis included studies that compared healthy older adults and adults with a clinical diagnosis of MCI on fine motor tasks such as handwriting, finger tapping, and hand dexterity.ResultTen studies with over 800 participants qualified for inclusion. Rigorous meta‐analytic techniques using random effects model, forest and funnels plots revealed a standardized mean difference effect of 0.48 (95% CI = 0.77 to 0.19, p=0.001). This moderate effect indicated deficits in fine motor control are a likely feature of MCI.ConclusionThe cumulative evidence suggests that fine motor impairments are pervasive in MCI across a range of upper extremity motor tasks. Quantitative assessment of the decline in fine motor function in MCI may be promising approach to understand the changes in motor function that occur with the onset of Alzheimer’s disease and are clearly differentiated from normal aging‐related decline.

Olfactory Decline in Older Adults with Mild Cognitive Impairment with and without Comorbidities.

Over the past two decades, several studies have measured olfactory performance in Mild Cognitive Impairment (MCI). Deficits are observed in multiple olfactory domains, including odour detection threshold, identification, discrimination, and memory. In this study, the psychophysiological Sniffin’ Sticks smell screening test was administered to examine olfactory functioning in 145 older adults with MCI, a group with MCI and chronic comorbid conditions, and a healthy age-matched comparison group. We hypothesised that olfactory performance will deteriorate in the two MCI groups compared to the control group, even after assessing the known contributions of age and gender. The higher olfactory deterioration in the group with the MCI and the comorbidities in the first year disappeared in the second. This could mean that early consideration of the potential effect of other comorbidities that might affect olfaction should be taken and addressed, as they could easily mask the effect of cognitive decline and/or contribute to it. This study also found higher deterioration in smell identification in participants with MCI, as has been found repeatedly in similar research. Olfactory identification seems to be a more robust marker for discriminating people with MCI and without, and even discriminating between those with MCI and having other health problems.

Traditional Thai exercise (Ruesi Dadton) for improving motor and cognitive functions in mild cognitive impairment: a randomized controlled trial.

This study determined the effectiveness of a 12-week cycle of Ruesi Dadton (RSD) among older adults with mild cognitive impairment (MCI), for improving cognitive and physical performance. Seventy-six participants were included and were divided equally into two groups. A group performed RSD exercise for 60 min, 3 times/wk for 12 weeks, and the control group did not perform RSD exercise. The primary endpoint was cognitive function, as assessed by the Montreal cognitive assessment (MoCA), Mini-Mental State Examination, verbal fluency (VF) test, and trail making test parts A and B (TMT-A and TMT-B). The secondary endpoints were the Timed Up and Go (TUG) test, handgrip, and gait speed results, which were used to evaluate the physical function. There were significant differences in the TMT-B and handgrip scores (P<0.05) between the two groups. Both groups had improved MoCA scores (P<0.05) and normal walking speeds (P<0.01). Additionally, the RSD group showed improved VF test (P<0.01), TMT-B (P<0.01), and TUG test (P<0.05); a negative correlation was found between MoCA and TUG test (P<0.05). However, high walking speed and handgrip (P<0.05) worsened in the control group. RSD exercise resulted in relevant improvements in the cognitive and physical functions in MCI.

Social Cognition and Social Functioning in MCI and Dementia in an Epidemiological Sample

Social cognition is impaired in mild cognitive impairment (MCI) and dementia. However, its relationship to social functioning and perceived social support has yet to be explored. Here, we examine how theory of mind (ToM) relates to social functioning in MCI and dementia. Older adults (cognitively normal = 1272; MCI = 132; dementia = 23) from the PATH Through Life project, a longitudinal, population-based study, were assessed on the Reading the Mind in the Eyes Test (RMET), measures of social functioning, and social well-being. The associations between RMET performance, social functioning, and cognitive status were analysed using generalised linear models, adjusting for demographic variables. Participants with MCI (b=-.52, 95% CI [-.70, -.33]) and dementia (b=-.78, 95% CI [-1.22, -.34]) showed poorer RMET performance than cognitively normal participants. Participants with MCI and dementia reported reduced social network size (b=-.21, 95% CI [-.40, -.02] and b=-.90, 95% CI [-1.38, -.42], respectively) and participants with dementia reported increased loneliness (b = .36, 95% CI [.06, .67]). In dementia, poorer RMET performance was associated with increased loneliness (b=-.07, 95% CI [-.14, -.00]) and a trend for negative interactions with partners (b=-.37, 95% CI [-.74, .00]), but no significant associations were found in MCI. MCI and dementia were associated with poor self-reported social function. ToM deficits were related to poor social function in dementia but not MCI. Findings highlight the importance of interventions to address social cognitive deficits in persons with dementia and education of support networks to facilitate positive interactions and social well-being.

Discourse performance and related cognitive function in mild cognitive impairment and dementia: A preliminary study

Objectives This study applied the discourse task and related cognitive items of the Brief Test of Cognitive-Communication Disorders (BCCD) to normal, mild cognitive impairment (MCI), and moderate dementia groups and compared the scores of each area. In addition, the cognitive functions affecting the discourse performance were investigated by group. Participants 117 normal adults, 38 MCI, and 31 patients with moderate dementia (DEM) conducted BCCD, including discourse and cognitive items. Design/setting The discourse item included repeating an explanatory discourse, and the total discourse score was calculated by summing the scores for each of the four areas of coherence, cohesion, proposition, and pause. The cognitive areas of BCCD were attention, visuospatial ability, memory, organization, reasoning, problem-solving, and executive function. This study performed a one-way multivariate analysis of covariance to compare the scores of the three groups and multiple regression analysis determined the cognitive functions influencing the total discourse score. Measurements The discourse scores reporting differences among all groups were the pause and the total discourse scores, with the normal group showing a higher performance than the patient groups in the cohesion score and the DEM group in the propositions score, respectively. In addition, the cognitive functions affecting discourse performance were attention, organization, and problem-solving in the normal group, and organization and problem-solving in the MCI group. Conclusions Organizing information into a series of semantic units related to each other is necessary for coherent and efficient utterances, and the ability to correctly recognize the task and establish a strategy to grasp the core content is necessary for pragmatic language.

TACS as a promising therapeutic option for improving cognitive function in mild cognitive impairment: A direct comparison between tACS and tDCS

Neuromodulation has gained attention as a potential non-pharmacological intervention for mild cognitive impairment (MCI). However, no studies have directly compared the effects of transcranial alternating current stimulation (tACS) with transcranial direct current stimulation (tDCS) on MCI patients. We aimed to identify the more promising and efficient therapeutic option between tACS and tDCS for cognitive enhancement in MCI patients. We compared the effects of gamma-tACS with tDCS on cognitive function and electroencephalography (EEG) in MCI patients. In this sham-controlled, double-blinded, repeated-measures study with the order of the stimulation counterbalanced across patients (n = 20), both gamma-tACS (40 H z) and tDCS were administered at the same intensity (2 mA) in the dorsolateral prefrontal cortex for 30 min. Cognitive tests (Stroop and Trail-Making-Test [TMT]) and EEG were performed before and after single-session stimulation. Gamma-tACS improved the Stroop-color in comparison with tDCS (p = .044) and sham (p = .010) and enhanced the TMT-B in comparison with sham (p = .021). However, tDCS was not significantly different from sham in changes of any cognitive test scores. In EEG analysis, gamma-tACS increased beta activity in comparison with sham and tDCS, whereas tDCS decreased delta and theta activity in comparison with sham. Gamma-tACS also increased beta 2 source activity in the anterior cingulate, compared to sham. The cognitive benefits of tACS in MCI patients appeared superior to those of tDCS. tACS facilitated cognitive function by increasing beta activity, while tDCS delayed the progression of MCI symptoms by decreasing slow-frequency activity. Thus, tACS could be used as a new therapeutic option for MCI.

Blood-Brain Barrier Breakdown in Relationship to Alzheimer and Vascular Disease.

Objective:Blood–brain barrier (BBB) breakdown has been suggested to be an early biomarker in human cognitive impairment. However, the relationship between BBB breakdown and brain pathology, most commonly Alzheimer disease (AD) and vascular disease, is still poorly understood. The present study measured human BBB function in mild cognitive impairment (MCI) patients on 2 molecular scales, specifically BBB’s permeability to water and albumin molecules.Methods:Fifty-five elderly participants were enrolled, including 33 MCI patients and 22 controls. BBB permeability to water was measured with a new magnetic resonance imaging technique, water extraction with phase contrast arterial spin tagging. BBB permeability to albumin was determined using cerebrospinal fluid (CSF)/serum albumin ratio. Cognitive performance was assessed by domain-specific composite scores. AD pathology (including CSF Aβ and ptau) and vascular risk factors were examined.Results:Compared to cognitively normal subjects, BBB in MCI patients manifested an increased permeability to small molecules such as water but was no more permeable to large molecules such as albumin. BBB permeability to water was found to be related to AD markers of CSF Aβ and ptau. On the other hand, BBB permeability to albumin was found to be related to vascular risk factors, especially hypercholesterolemia, but was not related to AD pathology. BBB permeability to small molecules, but not to large molecules, was found to be predictive of cognitive function.Interpretation:These findings provide early evidence that BBB breakdown is related to both AD and vascular risks, but their effects can be differentiated by spatial scales. BBB permeability to small molecules has a greater impact on cognitive performance.