title: Ensemble Empirical Mode Decomposition Analysis of EEG Data Collected during a Contour Integration Task.
abstract: We discuss a data-driven analysis of EEG data recorded during a combined EEG/fMRI study of visual processing during a contour integration task. The analysis is based on an ensemble empirical mode decomposition (EEMD) and discusses characteristic features of event related modes (ERMs) resulting from the decomposition. We identify clear differences in certain ERMs in response to contour vs noncontour Gabor stimuli mainly for response amplitudes peaking around 100 [ms] (called P100) and 200 [ms] (called N200) after stimulus onset, respectively. We observe early P100 and N200 responses at electrodes located in the occipital area of the brain, while late P100 and N200 responses appear at electrodes located in frontal brain areas. Signals at electrodes in central brain areas show bimodal early/late response signatures in certain ERMs. Head topographies clearly localize statistically significant response differences to both stimulus conditions. Our findings provide an independent proof of recent models which suggest that contour integration depends on distributed network activity within the brain.
authors.affiliation: Department of Biology, Institute of Biophysics, University of Regensburg, Regensburg, Germany; Department of Linguistics, Literature and Culture, Institute of Information Science, University of Regensburg, Regensburg, Germany.
authors.forename: Karema
authors.initials: K
authors.lastname: Al-Subari
authors.affiliation: Department of Biology, Institute of Biophysics, University of Regensburg, Regensburg, Germany; Department of Linguistics, Literature and Culture, Institute of Information Science, University of Regensburg, Regensburg, Germany.
authors.forename: Saad
authors.initials: S
authors.lastname: Al-Baddai
authors.affiliation: Department of Electrical Engineering, Telecommunication and Informatics, Institut of Electrical Engineering and Electronics, Universidade de Aveiro, Aveiro, Portugal.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Tomé
authors.affiliation: Department of Psychology, Pedagogics and Sport, Institute of Experimental Psychology, University of Regensburg, Regensburg, Germany.
authors.forename: Gregor
authors.initials: G
authors.lastname: Volberg
authors.affiliation: Department of Linguistics, Literature and Culture, Institute of Information Science, University of Regensburg, Regensburg, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Hammwöhner
authors.affiliation: Department of Biology, Institute of Biophysics, University of Regensburg, Regensburg, Germany.
authors.forename: Elmar W
authors.initials: EW
authors.lastname: Lang
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D004569:Electroencephalography / Q000379:methods; D005071:Evoked Potentials; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008954:Models, Biological; D010775:Photic Stimulation; D055815:Young Adult