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Updated: May 6, 2026

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Published on: August 5, 2014

アルツハイマー病の病前段階におけるアミロイド関連のデフォルトモードネットワークの過剰結合とネットワーク特異性の経時的低下

Woo-Jin Cha¹, Evgeny J Chumin^2,3, Dahyun Yi⁴

¹Department of Neuropsychiatry, Seoul National University Hospital, Seoul, Republic of Korea.

Alzheimer's & dementia : the journal of the Alzheimer's Association

|January 30, 2026

要旨

Introduction:

We investigated stage-specific alterations in functional connectivity (FC) of the default mode network (DMN) across the Alzheimer's disease (AD) continuum and tested whether early amyloid beta (Aβ)-related changes in within-DMN FC (DMN-FC_within) predicted longitudinal alterations in DMN between-network connectivity (DMN-FC_between).

Methods:

Resting-state functional magnetic resonance imaging (fMRI) data were analyzed from 396 older adults: Aβ-negative cognitively normal (CN-, n = 213), Aβ-positive CN (CN+, n = 37), Aβ-positive mild cognitive impairment (MCI+, n = 72), and Aβ-positive dementia (dementia+, n = 74). Cross-sectional analyses compared DMN-FC across groups and examined associations with continuous Aβ burden at baseline. Longitudinal analyses in 171 CN participants with 2-year follow-up (CN-, n = 147; CN+, n = 24) tested whether baseline DMN-FC_within predicted changes in DMN-FC_between.

Results:

CN+ individuals showed elevated DMN-FC_within and reduced DMN-FC_between relative to other groups. In CN, Aβ burden was associated with FC, and baseline DMN-FC_within predicted longitudinal increases in DMN-FC_between only in CN+.

Discussion:

Aβ-related hyperconnectivity characterizes preclinical AD and may drive progressive network-level vulnerability.

Highlights:

Cognitively normal amyloid beta (Aβ)-positive (CN+) individuals showed stronger connectivity within the default mode network (DMN). CN+ individuals also showed weaker links between the DMN and other brain networks. Amyloid was not linked to connectivity changes in cognitively impaired adults. Higher DMN connectivity predicted broader network changes in CN+ individuals.

キーワード:

アルツハイマー病 KBASE アミロイドβ デフォルトモードネットワーク機能的結合過剰結合

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The 4 Mountains Test: A Short Test of Spatial Memory with High Sensitivity for the Diagnosis of Pre-dementia Alzheimer's Disease

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Visualizing Axonal Growth Cone Collapse and Early Amyloid β Effects in Cultured Mouse Neurons

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Published on: October 30, 2018

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