Clinical Neurophysiology, Journal Year: 2019, Volume and Issue: 130(10), P. 1762 - 1780
Published: July 19, 2019
Language: Английский
Brain Communications, Journal Year: 2024, Volume and Issue: 6(6)
Published: Jan. 1, 2024
Neuronal dysfunction in specific brain regions or across distributed networks is a known feature of Alzheimer's disease. An often reported finding the early stage disease presence increased functional MRI (fMRI) blood oxygenation level-dependent signal under task conditions relative to cognitively normal controls, phenomenon as 'hyperactivation'. However, research past decades yielded complex, sometimes conflicting results. The magnitude and topology fMRI hyperactivation patterns have been found vary preclinical clinical spectrum disease, including concomitant 'hypoactivation' some cases. These incongruences are likely due range factors, at which cohort examined, areas studied paradigm utilized evoke these abnormalities. Additionally, perennial question pertains nature context Some propose it reflects compensatory mechanisms sustain cognitive performance, while others suggest linked pathological disruption highly regulated homeostatic cycle that contributes to, even drives, progression. Providing coherent narrative for empirical conceptual discrepancies paramount develop models, understand synergy between cascade tailor effective interventions. We first provide comprehensive overview changes spanning course from ageing then highlight evidence supporting close relationship
Language: Английский
Citations
6
Neurobiology of Aging, Journal Year: 2019, Volume and Issue: 79, P. 50 - 58
Published: March 8, 2019
We examined the relationships between amyloid-β PET and concurrent longitudinal cognitive performance in 107 cognitively normal individuals with subjective decline (age: 64 ± 8 years, 44% female, Mini-Mental State Examination score 29 1). All underwent 90-minute dynamic [18F]florbetapir scanning neuropsychological tests a mean follow-up of 3.4 3.0 years. Receptor parametric mapping was used to calculate binding potential (BPND), we performed linear mixed models assess global BPND performance. Higher related lower (β SE: −1.69 0.63 p < 0.01) steeper rate on tasks capturing memory (Rey Auditory Verbal Learning Task immediate [β SE −1.81 0.81, 0.05] delayed recall −1.19 0.34, 0.01]), attention/executive functions (Stroop II [color] −0.02 0.01, 0.05], Stroop III [word-color] −0.03 0.02, 0.05]), language (category fluency −0.04 0.01]). These findings suggest that higher load from clinic is associated cognition faster variety domains.
Language: Английский
Citations
54
NeuroImage Clinical, Journal Year: 2018, Volume and Issue: 21, P. 101612 - 101612
Published: Nov. 27, 2018
Subjective cognitive decline (SCD) patients are considered as a risk population for preclinical Alzheimer's Disease (AD). Supporting this idea, previous studies in SCD populations report subtle alterations various and neuroimaging biomarkers that typically affected during AD progression. To extend these observations, the present study examined whether show atrophy of cholinergic basal forebrain nuclei (chBFN), analogous with recent findings prodromal clinical patients. We assessed volume reductions chBFN 24 subjects compared to 49 matched controls on 3D-T1-weighted MR images based postmortem derived atlas. Furthermore, we was linked cognitive, structural metabolic biomarker previously reported cohort: Using correlation analyses tested associations between volumes hippocampal gray matter volume, posterior medial glucose consumption, trajectory verbal memory performance. The cases showed significant total reduction chBFN, largest effect sizes Ch1/2 Ch4p subdivisions chBFN. latter associated reduced metabolism precuneus group only. These data an early involvement predominantly which supports conceptual link AD.
Language: Английский
Citations
49
Frontiers in Aging Neuroscience, Journal Year: 2019, Volume and Issue: 11
Published: Jan. 24, 2019
Objective: Subjective cognitive decline (SCD) is associated with an increased risk of Alzheimer's Disease (AD). Early disease processes, such as amyloid-β aggregation measured quantitative PET, may help to explain the phenotype SCD. The aim this study was investigate whether load both self- and informant-reported complaints memory deficit awareness in individuals Methods: We included 106 SCD patients (mean ± SD age: 64 8, 45%F) 90 min dynamic [18F]florbetapir PET scans. used following questionnaires assess severity: change index (CCI, self informant reports; 2 × 20 items), subjective functioning (SCF, four five questions "Do you have complaints?" (yes/no) for memory, attention, organization language), "Does worry you? (yes/no)." Rivermead Behavioral Memory Test (RBMT)-Stories (immediate delayed recall) objective episodic memory. To level self-awareness, we calculated a (Z-transformed (inverted self-reported CCI minus memory); higher index, heightened self-awareness) self-proxy CCI). Mean cortical binding potential (BPND) derived from data. Logistic linear regression analyses, adjusted age, sex, education, depressive symptoms, were associations between BPND measures Results: Higher mean SCD-related worries (odds ratio = 1.76 [95%CI 1.07 2.90]), but not other (informant self-report or SCF, total scores individual items, all p > 0.05). In addition, (Beta 0.55), interaction education (p 0.002). There no 0.11). Conclusion: Amyloid-β deposition (i.e., hypernosognosia), severity complaints. Our findings indicate that about self-perceived reflect early symptom related pathology rather than functioning.
Language: Английский
Citations
48
Translational Neurodegeneration, Journal Year: 2018, Volume and Issue: 7(1)
Published: Oct. 19, 2018
Individuals with subjective memory complaints (SMC) feature a higher risk of cognitive decline and clinical progression Alzheimer's disease (AD). However, the pathological mechanism underlying SMC remains unclear. We aimed to assess intrinsic connectivity network its relationship AD-related pathologies in individuals.We included 44 individuals 40 normal controls who underwent both resting-state functional MRI positron emission tomography (PET). Based on graph theory approaches, we detected local global across whole brain by using degree centrality (DC) eigenvector (EC) respectively. Additionally, analyzed amyloid deposition tauopathy via florbetapir-PET imaging cerebrospinal fluid (CSF) data. The voxel-wise two-sample T-test analysis was used examine between-group differences cerebral deposition. Then, correlated these metrics results.The showed DC bilateral hippocampus (HP) left fusiform gyrus lower inferior parietal region than controls. Across all subjects, HP positively associated total tau phosphorylated tau181. no significant difference existed EC deposition.We found impaired local, but not global, networks individuals. Given relationships between value level, hypothesized that changes might relate biomarkers.
Language: Английский
Citations
47
Brain Communications, Journal Year: 2021, Volume and Issue: 3(4)
Published: Sept. 6, 2021
Abstract Cortical accumulation of amyloid beta is one the first events Alzheimer’s disease pathophysiology, and has been suggested to follow a consistent spatiotemporal ordering, starting in posterior cingulate cortex, precuneus medio-orbitofrontal cortex. These regions overlap with those default mode network, brain network also involved memory functions. Aberrant functional connectivity higher sparsity have reported prodromal clinical disease. We investigated association between burden preclinical stage its longitudinal decline. included 173 participants, which was assessed both CSF by 42/40 ratio, capturing soluble part pathology, dynamic PET scans calculating non-displaceable binding potential early-stage regions. The identified resting-state MRI. Then, we calculated derived from independent component analysis, eigenvector centrality, graph measure recursively defining important nodes on base their connection other nodes. Memory tested at baseline, 2- 4-year follow-up. demonstrated that as measured ratio cortex associated lower network. (CSF cortex) aberrant confirmed voxel level centrality measures, it driven clusters localized precuneus, cingulate, angular left middle temporal gyri. Moreover, predicts decline synergistically regional burden, Taken together, these results suggest early deposition cognitively healthy individuals markers can be used identify subjects risk
Language: Английский
Citations
33
Journal of Psychiatric Research, Journal Year: 2023, Volume and Issue: 159, P. 165 - 171
Published: Jan. 30, 2023
Language: Английский
Citations
16
Alzheimer s & Dementia, Journal Year: 2023, Volume and Issue: 19(11), P. 4922 - 4934
Published: April 18, 2023
It remains unclear whether functional brain networks are consistently altered in individuals with subjective cognitive decline (SCD) of diverse ethnic and cultural backgrounds the network alterations associated an amyloid burden.Cross-sectional resting-state magnetic resonance imaging connectivity (FC) amyloid-positron emission tomography (PET) data from Chinese Sino Longitudinal Study on Cognitive Decline German DZNE Impairment Dementia cohorts were analyzed.Limbic FC, particularly hippocampal right insula, was higher SCD than controls, correlated SCD-plus features. Smaller subcohorts PET showed inconsistent positivity rates FC-amyloid associations across cohorts.Our results suggest early adaptation limbic SCD, which may reflect increased awareness decline, irrespective pathology. Different indicate a heterogeneous underlying etiology Eastern Western when applying current research criteria. Future studies should identify culture-specific features to enrich preclinical Alzheimer's disease non-Western populations.Common hyperconnectivity observed. Limbic cognition, load. Further cross-cultural harmonization regarding pathology is required.
Language: Английский
Citations
16
Human Brain Mapping, Journal Year: 2019, Volume and Issue: 40(18), P. 5213 - 5230
Published: Aug. 24, 2019
Abstract Aging is characterized by accumulation of structural and metabolic changes in the brain. Recent studies suggest transmodal brain networks are especially sensitive to aging, which, we hypothesize, may be due their apical position cortical hierarchy. Studying an open‐access healthy cohort ( n = 102, age range 30–89 years) with MRI Aβ PET data, estimated age‐related thinning, hippocampal atrophy deposition. In addition carrying out surface‐based morphological mapping experiments, stratified effects along neocortical resting‐state functional connectome gradients derived from independent datasets. The gradient depicts axis differentiation sensory‐motor regions regions, whereas recapitulates its long‐axis. While thinning increased deposition occurred across entire topography, was pronounced toward higher‐order regions. Age‐related greater posterior end No significant effect on hippocampus observed. Imaging markers correlated behavioral measures fluid intelligence episodic memory a topography‐specific manner, confirmed using both univariate as well multivariate analyses. Our results strengthen existing evidence change aging support use connectivity compact framework analyze conceptualize brain‐based biomarkers aging.
Language: Английский
Citations
42
Journal of Neurology, Journal Year: 2020, Volume and Issue: 268(12), P. 4607 - 4629
Published: Oct. 31, 2020
Language: Английский
Citations
36