EEG network connectivity changes in mild cognitive impairment - Preliminary results

Area of Science:

• Neuroscience
• Cognitive Neurology
• Biomedical Engineering

Background:

• Mild cognitive impairment (MCI) is a transitional stage between normal aging and dementia.
• Understanding the neural underpinnings of MCI progression is crucial for early intervention.
• Functional brain connectivity alterations are increasingly implicated in cognitive decline.

Purpose of the Study:

• To investigate functional connectivity changes in patients with amnestic MCI (aMCI) compared to controls.
• To assess the longitudinal changes in brain connectivity over one year.
• To determine if connectivity patterns can predict MCI progression.

Main Methods:

• Resting-state electroencephalography (EEG) recorded over one year in aMCI patients and matched controls.
• EEG data analyzed for phase synchronization in different frequency bands (delta, theta, alpha1) under eyes-closed and eyes-open conditions.
• Comparison of local and large-scale functional connectivity between groups and over time.

Main Results:

• Decreased delta and theta band synchronization (local and large-scale connectivity) observed in aMCI patients, particularly in frontal, fronto-temporal, and fronto-parietal areas.
• This reduction in connectivity became more pronounced after one year in the aMCI group.
• Reduced alpha1 band connectivity upon eye opening in controls, absent in aMCI patients, differentiating the groups.

Conclusions:

• Functional disconnection between distant brain areas is a hallmark of aMCI.
• The observed pattern of decreased connectivity worsens over time in aMCI.
• Alpha1 band reactivity to eye opening is a potential biomarker for differentiating aMCI from healthy aging.