Decreased dorsal attention network homogeneity as a potential neuroimaging biomarker for major depressive disorder

Journal of Affective Disorders, Год журнала: 2023, Номер 332, С. 136 - 142

Опубликована: Март 28, 2023

Язык: Английский

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Disrupted brain functional connectivity as early signature in cognitively healthy individuals with pathological CSF amyloid/tau

Communications Biology, Год журнала: 2024, Номер 7(1)

Опубликована: Авг. 23, 2024

Alterations in functional connectivity (FC) have been observed individuals with Alzheimer's disease (AD) elevated amyloid (Aβ) and tau. However, it is not yet known whether directed FC already influenced by Aβ tau load cognitively healthy (CH) individuals. A 21-channel electroencephalogram (EEG) was used from 46 CHs classified based on cerebrospinal fluid (CSF) ratio: pathological (CH-PAT) or normal (CH-NAT). Directed estimated Partial Coherence frontal, temporal, parietal, central, occipital regions. We also examined the correlations between various metrics, including neuropsychology, cognitive reserve, MRI volumetrics, heart rate variability both groups. Compared to CH-NATs, CH-PATs showed decreased temporal regions, indicating a loss of relative importance In addition, frontal regions enhanced compared suggesting neural compensation for damage caused pathology. Moreover, greater than CH-NATs. Our findings provide useful non-invasive method EEG-based analysis identify alterations brain versus CSF Aβ/tau. This study reveals disrupted as an early biomarker amyloid/tau, aiding detection.

Язык: Английский

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Correlations between plasma markers and brain Aβ deposition across the AD continuum: Evidence from SILCODE

Alzheimer s & Dementia, Год журнала: 2024, Номер 20(9), С. 6170 - 6182

Опубликована: Июль 10, 2024

Abstract BACKGROUND Previous studies have found that Alzheimer's disease (AD)‐related plasma markers are associated with amyloid beta (Aβ) deposition, but the change of this association in different Aβ pathological stages remains unclear. METHODS Data were obtained from SILCODE. According to standardized uptake value ratio (SUVR) and stage classification, correlation analysis was performed among biomarkers, voxel/SUVR values regions interest (ROI) clinical scale information, respectively. Mediation used study possible pathways. RESULTS The proportion cognitively normal (CN) subjective cognitive decline (SCD) highest A0 1, while A2 4, mild impairment (MCI) AD increased. Plasma phosphorylated tau (p‐tau)181 glial fibrillary acidic protein (GFAP) levels significantly lower compared later phases. Two pathways demonstrated fully mediated effects: positron emission tomography (PET) SUVR–plasma p‐tau181–Mini‐Mental State Examination (MMSE) PET GFAP–MMSE. DISCUSSION This role biomarkers early AD, especially SCD, both diagnosis dimensions. Highlights ptau181 GFAP level serve as indicators pathologic staging classification. A ceiling effect observed mid‐to‐late course. confirms promoting deposition at an stage, particularly females decline(SCD). overlapping brain p‐tau181, GFAP, neurofilament light for distributed across various regions, including posterior cingulate gyrus, rectus inferior temporal gyrus.

Язык: Английский

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Subjective cognitive decline: Memory complaints, cognitive awareness, and metacognition

Alzheimer s & Dementia, Год журнала: 2024, Номер 20(9), С. 6622 - 6631

Опубликована: Июль 25, 2024

Abstract Cognitive complaints are common in elderly subjects and a frequent reason for referral to memory clinics. If the not associated with objective cognitive impairment, condition is labelled subjective decline (SCD). SCD often considered as stage antedating an at‐risk subsequent dementia. Recent large‐scale studies indicate that significantly increased risk of clinical progression positivity Alzheimer's disease (AD) biomarkers, finding supporting notion can be due different mechanisms neurodegeneration, including functional disorders. In this paper we present selective review research on relations among SCD, awareness, metacognitive abilities. We propose longitudinal efficiency may provide useful cues about dementia possible presence disorder, implications management prevalent aging‐related condition. Highlights Subjective (SCD), cause clinics, multiple conditions. The predictive value high association AD biomarker positivity. awareness mechanism responsible emergence metacognition underlying neuropsychological function. patients usually assessed comparing informant rating patient self‐assessment, method affected by bias. While there strong evidence starts onset progressively leading anosognosia AD, status needs further investigated. Quantitative, performance‐based indexes contribute both assessment

Язык: Английский

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Impaired olfactory identification in dementia-free individuals is associated with the functional abnormality of the precuneus

Neurobiology of Disease, Год журнала: 2024, Номер 194, С. 106483 - 106483

Опубликована: Март 26, 2024

Olfactory dysfunction indicates a higher risk of developing dementia. However, the potential structural and functional changes are still largely unknown. A total 236 participants were enrolled, including 45 Alzheimer's disease (AD) individuals 191dementia-free individuals. Detailed study methods, comprising neuropsychological assessment olfactory identification test (University Pennsylvania smell test, UPSIT), as well magnetic resonance imaging (MRI) applied in this research. The dementia-free divided into two sub-groups based on score: with (DF-OD) sub-group without (DF-NOD) sub-group. results analyzed for subsequent intergroup comparisons correlations. cognitive was conducted again three years later. (i) At stage, there positive correlation between score function. (ii) In group, volume crucial brain structures involved recognition processing (such amygdala, entorhinal cortex basal forebrain volumes) positively associated score. (iii) Compared to DF-NOD DF-OD group showed significant reduction network (ON) (iv) connectivity (FC) decline PCun_L(R)_4_1 precuneus posterior default mode (pDMN) salience (SN) FC values decreased falling scores. Moreover, noteworthy observed which component ON. (v) AD conversion rate 29.41%, while 12.50%. also more severe. addition circuit, is critical structure odor process, whose abnormal function underlies impairment

Язык: Английский

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Alterations in functional connectivity in individuals with subjective cognitive decline and hippocampal atrophy

International Psychogeriatrics, Год журнала: 2025, Номер unknown, С. 100067 - 100067

Опубликована: Март 1, 2025

The aim of this study was to determine whether individuals with Subjective Cognitive Decline (SCD), particularly those a neurostructural marker risk for AD (SCD+), exhibit differences in the functional connectivity Default-Mode Network (DMN) relative controls, as network is known be altered continuum. Cross-sectional study. Galicia, Northwest Spain. sample compromised 133 participants: 69 51 SCD and 13 SCD+. Seed-to-voxel analysis conducted using four DMN ROIs. Dynamic independent component also performed. SCD+ groups exhibited hyperconnectivity, which more extensive group. Increased anti-correlations between task-positive parietal regions were related poorer executive scores tendency higher recurrence Hippocampal atrophy biomarker associated hyperconnectivity increased regions.

Язык: Английский

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Resting-state Functional Brain Networks in Hypertensive Retinopathy

Brain Research Bulletin, Год журнала: 2025, Номер unknown, С. 111350 - 111350

Опубликована: Апрель 1, 2025

Язык: Английский

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Hyperbolic graph embedding of MEG brain networks to study brain alterations in individuals with subjective cognitive decline

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Окт. 25, 2023

Abstract An expansive area of research focuses on discerning patterns alterations in functional brain networks from the early stages Alzheimer’s disease, even at subjective cognitive decline (SCD) stage. Here, we developed a novel hyperbolic MEG network embedding framework for transforming high-dimensional complex into lower-dimensional representations. Using this model, computed embeddings two distinct participant groups: individuals with SCD and healthy controls. We demonstrated that these preserve both local global geometric information, presenting reduced distortion compared to rival models, when are mapped low-dimensional spaces. In addition, our findings showed encompass unique SCD-related information improves discriminatory power above beyond connectivity features alone. Notably, introduced metric—the radius node embeddings—which effectively proxies hierarchical organization brain. metric, identified subtle hierarchy organizational differences between groups, suggesting increased dorsal attention, frontoparietal, ventral attention subnetworks among group. Last, assessed correlation variations assessment scores, revealing associations diminished performance across multiple evaluations Overall, study presents first evaluation networks, offering insights organization, decline, potential diagnostic avenues disease.

Язык: Английский

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Static and dynamic functional connectivity combined with the triple network model in amnestic mild cognitive impairment and Alzheimer's disease

Frontiers in Neurology, Год журнала: 2023, Номер 14

Опубликована: Ноя. 17, 2023

Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) are characterized by abnormal functional connectivity (FC) of default-mode network (DMN), salience (SN), central executive (CEN). Static FC (sFC) dynamic (dFC) combined with triple model can better study the static changes brain networks, improve its potential diagnostic value in diagnosis AD spectrum disorders.Differences sFC values dFC variability patterns among three networks groups (53 patients, 40 aMCI NCs) were computed ANOVA using Gaussian Random Field theory (GRF) correction. The correlation between (sFC variability) scores (MMSE MoCA) was analyzed separately.Within DMN network, there significant differences right/left medial superior frontal gyrus left opercular part inferior right dorsolateral groups. Within CEN parietal gyrus. SN Cerebelum_7b In addition, a negative SN) MMSE MoCA scores.It suggests that sFC, be considered as biomarkers for aMCI.

Язык: Английский

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Association of precuneus Aβ burden with default mode network function

Alzheimer s & Dementia, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 19, 2024

Abstract INTRODUCTION It remains unclear whether the local amyloid‐beta (Aβ) burden in key regions within default mode network (DMN) affects and cognitive functions. METHODS Participants included 1002 individuals from Chinese Preclinical Alzheimer's Disease Study cohort who underwent 18F‐florbetapir positron emission tomography resting‐state functional magnetic resonance imaging scanning neuropsychological tests. The correlations between precuneus (PRC) Aβ burden, DMN function, function were investigated. RESULTS In with high PRC there is a bidirectional relationship or connectivity deposition across various states, which also linked to function. Even below threshold, related performance. DISCUSSION findings reveal critical role of disrupting neural networks associated decline necessity early detection monitoring deposition. Highlights Precuneus impacts different stages. High compensation subsequent dysfunction. Low correlates changes before significant accumulation. Changes provide insights into AD progression. Early regional can help monitor risk decline.

Язык: Английский

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