Related Experiment Video
Updated: Feb 20, 2026
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Application of Granger Causality Analysis of the Directed Functional Connection in Alzheimer's Disease and Mild Cognitive Impairment
Published on: August 7, 2017
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Default mode network connectivity is associated with executive and language performance in mild cognitive impairment
Hamide Nasiri1, Behadad Mohammadtaheri1, Farbod Khosravi2
1Student Research Committee, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
Neuroscience Letters
|February 18, 2026
Summary
Default mode network (DMN) connectivity disruptions impact cognition differently across Alzheimer's disease (AD) stages. In mild cognitive impairment (MCI), weaker DMN connectivity is linked to poorer executive function and language, but not memory.
Area of Science:
- Neuroscience
- Cognitive Neurology
- Neuroimaging
Background:
- Default mode network (DMN) connectivity alterations are observed in Alzheimer's disease (AD).
- The specific relationship between DMN functional connectivity and distinct cognitive domains across the AD continuum is not fully understood.
Purpose of the Study:
- To investigate the association between anterior and posterior DMN functional connectivity and memory, executive function, and language performance.
- To examine these relationships across cognitively normal, mild cognitive impairment (MCI), and AD populations.
Main Methods:
- Cross-sectional analysis of resting-state fMRI data from 154 participants (61 controls, 68 MCI, 25 AD).
- DMN connectivity metrics derived from region-of-interest-to-voxel correlations in anterior (aDMN) and posterior (pDMN) subdivisions.
- Multiple linear regression used to assess associations between DMN measures and cognitive scores, adjusted for covariates and corrected for multiple comparisons.
Main Results:
- No significant association found between DMN connectivity and memory performance in any group.
- In the MCI group, weaker anterior-posterior DMN connectivity correlated with poorer executive function and language performance.
- These DMN-cognition associations were specific to the MCI group and not observed in cognitively normal or AD groups, even after adjusting for white matter hyperintensities.
Conclusions:
- DMN connectivity-cognition relationships are domain-specific and most prominent in the MCI stage.
- Findings suggest that altered network-level functional organization in MCI is related to specific cognitive deficits.
- This highlights MCI as a transitional stage where DMN integrity may predict cognitive outcomes.
Keywords:
Alzheimer’s diseaseCognitive declineDefault mode networkExecutive functionFunctional connectivityMild cognitive impairmentfMRIMore Related Videos
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