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Updated: May 8, 2026
07:13
Cerebral Blood Flow-Based Resting State Functional Connectivity of the Human Brain using Optical Diffuse Correlation Spectroscopy
Published on: May 27, 2020
Cerebrospinal fluid Aβ42, phosphorylated Tau181, and resting-state functional connectivity
JAMA Neurology
|August 21, 2013
Summary
Alzheimer disease pathology, including amyloid-beta and tau, impacts the brain's default mode network before symptoms appear. This study used MRI to link biomarkers to network changes in cognitively normal individuals.
Area of Science:
- Neuroimaging
- Biomarkers
- Alzheimer's Disease Research
Background:
- Resting-state functional connectivity MRI shows promise for detecting preclinical Alzheimer disease.
- Early detection of Alzheimer disease pathology is crucial for intervention.
Purpose of the Study:
- To investigate the association between default mode network (DMN) integrity and Alzheimer disease cerebrospinal fluid (CSF) biomarkers.
- To examine these relationships in cognitively normal older adults.
Main Methods:
- A cross-sectional study of 207 cognitively normal older adults was conducted.
- Resting-state functional connectivity MRI was used to measure DMN integrity.
- CSF levels of amyloid-beta 42 (Aβ42) and phosphorylated tau 181 (p-tau181) were analyzed.
Main Results:
- Reduced DMN integrity was associated with lower CSF Aβ42 and higher CSF p-tau181.
- The strongest connectivity decreases were seen between the posterior cingulate and medial temporal regions.
- These findings were independent of age and structural atrophy.
Conclusions:
- Alzheimer disease-related amyloid and tau pathologies impact DMN integrity prior to clinical symptom onset.
- This suggests DMN functional connectivity is an early indicator of Alzheimer disease pathology.
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