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State-dependent functional network connectivity alterations in post-stroke dementia with subcortical lesions
Huaying Cai1, Nan Zhang2, Yun Jiang1
1Department of Neurology, Neuroscience Center, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, China.
Journal of Alzheimer'S Disease : JAD
|February 27, 2025
Summary
Post-stroke dementia (PSD) shows unique dynamic functional network connectivity (dFNC) changes, revealing both impairment and compensation in brain networks, unlike static connectivity patterns.
Area of Science:
- Neuroscience
- Cognitive Neurology
- Medical Imaging
Background:
- Disrupted dynamic functional network connectivity (dFNC) is observed in stroke and dementia.
- Specific dFNC alterations in post-stroke dementia (PSD) remain largely unexplored.
Purpose of the Study:
- To investigate PSD-specific alterations in dFNC.
- To examine the relationship between dFNC and cognitive function in PSD patients.
Main Methods:
- Resting-state functional magnetic resonance imaging (fMRI) was used in normal controls (NC), PSD, and post-stroke non-dementia (PSND) groups.
- Independent component analysis with a sliding-window approach calculated dFNC.
- Cognitive assessments (Mini-Mental State Examination, MiniCog) were correlated with dFNC measures.
Main Results:
- Four distinct dFNC states were identified.
- PSD and PSND showed increased visual network (VN) connectivity in state III compared to NC.
- PSD exhibited weaker default mode network (DMN) and VN connectivity in state I compared to PSND.
- dFNC measures significantly correlated with cognitive assessments.
Conclusions:
- PSD-specific dFNC alterations are state-dependent.
- dFNC reveals a dual mechanism of functional impairment and compensation in PSD brain networks.
- Dynamic FNC offers a novel perspective on the neural underpinnings of PSD, not evident in static FNC.
Keywords:
Alzheimer's diseasebrain networkdynamic functional connectivitypost-stroke dementiaresting-state functional MRIMore Related Videos
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