Conjoint Observation of Distinct Oscillatory Brain States in Intracranial and Scalp EEG

Abstract

We systematically analyzed the relationship between oscillatory spatial-temporal patterns identified from invasive electrocorticography (ECoG) and scalp EEG. We first performed a fuzzy classification of the principal components of cortical oscillatory activity as one of the three types: localized sources, static waves (distributed oscillators) and propagating waves. Next, we evaluated how this cortical activity correlated with the scalp EEG. Our findings indicate that the scalp EEG best represents, at any frequency, the static wave type of synchronized activity. This observation may aid a more accurate interpretation of the scalp EEG and contribute to the definition of source localization models.