A Novel Method for the Characterization of Synchronization and Coupling in Multichannel EEG and ECoG

In this paper we introduce a novel method for the characterization of synchronziation and coupling effects in multivariate time series that can be used for the analysis of EEG or ECoG signals recorded during epileptic seizures. The method allows to visualize the spatio-temporal evolution of synchronization and coupling effects that are characteristic for epileptic seizures. Similar to other methods proposed for this purpose our method is based on a regression analysis. However, a more general definition of the regression together with an effective channel selection procedure allows to use the method even for time series that are highly correlated, which is commonly the case in EEG/ECoG recordings with large numbers of electrodes. The method was experimentally tested on ECoG recordings of epileptic seizures from patients with temporal lobe epilepsies. A comparision with the results from a independent visual inspection by clinical experts showed an excellent agreement with the patterns obtained with the proposed method.

Authors:

• Manfred Hartmann
• Andreas Graef
• Hannes Perko
• Christoph Baumgartner
• Tilmann Kluge

Keywords:

• EEG
• epilepsy
• regression analysis
• seizurepropagation.

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