title: A periodic spatio-spectral filter for event-related potentials.
abstract: With respect to single trial detection of event-related potentials (ERPs), spatial and spectral filters are two of the most commonly used pre-processing techniques for signal enhancement. Spatial filters reduce the dimensionality of the data while suppressing the noise contribution and spectral filters attenuate frequency components that most likely belong to noise subspace. However, the frequency spectrum of ERPs overlap with that of the ongoing electroencephalogram (EEG) and different types of artifacts. Therefore, proper selection of the spectral filter cutoffs is not a trivial task. In this research work, we developed a supervised method to estimate the spatial and finite impulse response (FIR) spectral filters, simultaneously. We evaluated the performance of the method on offline single trial classification of ERPs in datasets recorded during an oddball paradigm. The proposed spatio-spectral filter improved the overall single-trial classification performance by almost 9% on average compared with the case that no spatial filters were used. We also analyzed the effects of different spectral filter lengths and the number of retained channels after spatial filtering.
authors.affiliation: Human Computer Interaction Lab. Faculty of Electrical and Computer Engineering, Tarbiat Modares University, Tehran, Iran. Electronic address: fghaderi@modares.ac.ir.
authors.forename: Foad
authors.initials: F
authors.lastname: Ghaderi
authors.affiliation: Robotics Innovation Center (RIC), German Research Center for Artificial Intelligence (DFKI), Bremen, Germany.
authors.forename: Su Kyoung
authors.initials: SK
authors.lastname: Kim
authors.affiliation: Robotics Innovation Center (RIC), German Research Center for Artificial Intelligence (DFKI), Bremen, Germany & Robotics Group, University of Bremen, Bremen, Germany.
authors.forename: Elsa Andrea
authors.initials: EA
authors.lastname: Kirchner
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000502:physiology; D062207:Brain-Computer Interfaces; D004569:Electroencephalography / Q000379:methods*; D005071:Evoked Potentials / Q000502:physiology*; D006801:Humans; D008297:Male; D012815:Signal Processing, Computer-Assisted
keywords: Brain-computer interface (BCI); Electroencephalogram; Event-related potential (ERP) detection; Spatial filters; Spatio-spectral filters