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Alois Schlögl University of Technology Graz, Austria <alois.schloegl@tugraz.at>. Analyzing EEG Coupling. COST B27 ENOC Joint WGs Meeting Swansea UK, 16-18 September 2006. Offer: Methods for analysing EEG coupling using Multivariate autoregressive modelling
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Alois Schlögl University of Technology Graz, Austria <alois.schloegl@tugraz.at> Analyzing EEG Coupling COST B27 ENOC Joint WGs Meeting Swansea UK, 16-18 September 2006
Offer: • Methods for analysing EEG coupling using Multivariate autoregressive modelling • Coherency, PDC, DTF, phase, etc. • BioSig http://biosig.sf.net • Asking for: • EEG data on interesting research topics • collaboration
Multivariate AutoRegressive (MVAR) models • Multivariate: spatio-temporal correlation • Estimators: • Levinson-Wiggins-Robinson (LWR): Multivariate Yule-Walker • Nutall-Strand method (multivariate burg method) • Vieira-Morf (multivariate geometric lattice) • Software: • TSA-toolbox: MVAR.M • BioSig http://biosig.sf.net Schlögl (2006), Comparison of MVAR estimators, Signal Processing.
Time-Frequency AnalysisPDC (Hypothesis: PDC>0) Subject K3 Left hand 1 0 Coupling almost all the time in all frequencies !?
Event-related PDC (Hypothesis: PDC != ref) Subject K3 Left hand ref=pdc(0-3s) pdc>ref pdc<ref Increases and decreases of coupling can be observed !
MVAR estimators Comparison of • ARFIT • Multichannel Yule-Walker • Multichannel Burg (Nutall-Strand) Schlögl, A. (2006) Comparison of Multivariate Autoregressive Estimators.Signal processing
Signal processing (II) • Spectrum • Coherence (absCOH, imagCOH) • Partial coherence (pCOH) • Partial directed coherence (PDC) • Directed transfer function (DTF) • Full-Frequency DTF (ffDTF) • Directed coupling (DC) • Phase
Directed transfer function DTF & partial directed coherence (PDC)
Thank You for the Attention • References: • Schlögl, 2006, Comparison of Multivariate Autoregressive Estimators.Signal processing • Schlögl and Supp (in press), Progress In Brain Research Contact: Alois Schlögl alois.schloegl@tugraz.at http://biosig.sf.net
DTF (Hypothesis: DTF>0) Subject K3 Left hand 1 0 Coupling almost all the time in all frequencies !?
Event-related PDC (Hypothesis: PDC != ref) Subject K3 Right hand ref=pdc(0-3s) pdc>ref pdc<ref Increases and decreases of coupling can be observed !