AUTHOR=Schmidt Magali , Kanda Paulo , Basile Luis , da Silva Lopes Helder F., Baratho Regina , Demario Jose , Jorge Mario , Nardi Antonio , Machado Sergio , Ianof Jessica N., Anghinah Renato , Nitrini Ricardo 

TITLE=Index of Alpha/Theta Ratio of the Electroencephalogram: A New Marker for Alzheimer’s Disease

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=5

YEAR=2013

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2013.00060

DOI=10.3389/fnagi.2013.00060

ISSN=1663-4365

ABSTRACT=<p><bold>Objective:</bold> We evaluated quantitative EEG measures to determine a screening index to discriminate Alzheimer’s disease (AD) patients from normal individuals.</p><p><bold>Methods:</bold> Two groups of individuals older than 50 years, comprising a control group of 57 normal volunteers and a study group of 50 patients with probable AD, were compared. EEG recordings were obtained from subjects in a wake state with eyes closed at rest for 30 min. Logistic regression analysis was conducted.</p><p><bold>Results:</bold> Spectral potentials of the alpha and theta bands were computed for all electrodes and the alpha/theta ratio calculated. Logistic regression of alpha/theta of the mean potential of the C3 and O1 electrodes was carried out. A formula was calculated to aid the diagnosis of AD yielding 76.4% sensitivity and 84.6% specificity for AD with an area under the ROC curve of 0.92.</p><p><bold>Conclusion:</bold> Logistic regression of alpha/theta of the spectrum of the mean potential of EEG represents a good marker discriminating AD patients from normal controls.</p>