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Mild Cognitive Impairment: Structural, Metabolical, and Neurophysiological Evidence of a Novel EEG Biomarker
1IRCCS San Giovanni di Dio Fatebenefratelli , Brescia , Italy.
Background:
Recent studies demonstrate that the alpha3/alpha2 power ratio correlates with cortical atrophy, regional hypoperfusion, and memory impairment in subjects with mild cognitive impairment (MCI).
Methods:
Evidences were reviewed in subjects with MCI, who underwent EEG recording, magnetic resonance imaging (MRI) scans, and memory evaluation. Alpha3/alpha2 power ratio (alpha2 8.9-10.9 Hz range; alpha3 10.9-12.9 Hz range), cortical thickness, linear EEG coherence, and memory impairment have been evaluated in a large group of 74 patients. A subset of 27 subjects within the same group also underwent single photon emission computed tomography (SPECT) evaluation.
Results:
In MCI subjects with higher EEG upper/low alpha power ratio, a greater temporo-parietal and hippocampal atrophy was found as well as a decrease in regional blood perfusion and memory impairment. In this group, an increase of theta oscillations is associated with a greater interhemispheric coupling between temporal areas.
Conclusion:
The increase of alpha3/alpha2 power ratio is a promising novel biomarker in identifying MCI subjects at risk for Alzheimer's disease.
Insights
The alpha3/alpha2 power ratio may indicate Alzheimer's disease risk in mild cognitive impairment (MCI) patients. Higher ratios correlate with brain atrophy, reduced blood flow, and memory loss.
Area of Science:
- Neuroscience
- Biomarkers
- Neuroimaging
Background:
- Mild cognitive impairment (MCI) is associated with brain changes.
- The alpha3/alpha2 power ratio shows correlation with cortical atrophy, hypoperfusion, and memory deficits in MCI.
Purpose of the Study:
- To investigate the alpha3/alpha2 power ratio as a potential biomarker for MCI progression.
- To correlate EEG power ratios with neuroimaging and cognitive measures in MCI patients.
Main Methods:
- Reviewed evidence from 74 MCI patients undergoing EEG, MRI, and memory tests.
- Evaluated alpha3/alpha2 power ratio, cortical thickness, EEG coherence, and memory impairment.
- Utilized SPECT imaging in a subset of 27 patients.
Main Results:
- Higher alpha3/alpha2 power ratio linked to increased temporo-parietal and hippocampal atrophy.
- Elevated ratios correlated with reduced regional blood perfusion and worsened memory impairment.
- Increased theta oscillations associated with greater temporal interhemispheric coupling.
Conclusions:
- The alpha3/alpha2 power ratio is a promising biomarker for identifying MCI patients at risk for Alzheimer's disease.
- This EEG-based ratio offers a novel, non-invasive method for risk assessment.
