AUTHOR=Moretti Davide Vito 

TITLE=Mild Cognitive Impairment: Structural, Metabolical, and Neurophysiological Evidence of a Novel EEG Biomarker

JOURNAL=Frontiers in Neurology

VOLUME=6

YEAR=2015

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2015.00152

DOI=10.3389/fneur.2015.00152

ISSN=1664-2295

ABSTRACT=<sec id="ST1"><title>Background</title><p>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).</p></sec><sec id="ST2"><title>Methods</title><p>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.</p></sec><sec id="ST3"><title>Results</title><p>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.</p></sec><sec id="ST4"><title>Conclusion</title><p>The increase of alpha3/alpha2 power ratio is a promising novel biomarker in identifying MCI subjects at risk for Alzheimer’s disease.</p></sec>