title: Extraction of cognitive activity-related waveforms from functional near-infrared spectroscopy signals.
abstract: We address the problem of prototypical waveform extraction in cognitive experiments using functional near-infrared spectroscopy (fNIRS) signals. These waveform responses are evoked with visual stimuli provided in an oddball type experimental protocol. As the statistical signal-processing tool, we consider the linear signal space representation paradigm and use independent component analysis (ICA). The assumptions underlying ICA is discussed in the light of the signal measurement and generation mechanisms in the brain. The ICA-based waveform extraction is validated based both on its conformance to the parametric brain hemodynamic response (BHR) model and to the coherent averaging technique. We assess the intra-subject and inter-subject waveform and parameter variability.
authors.affiliation: Department of Electrical and Electronics Engineering, Boğaziçi University, Istanbul, Turkey.
authors.forename: Ceyhun Burak
authors.initials: CB
authors.lastname: Akgül
authors.forename: Ata
authors.initials: A
authors.lastname: Akin
authors.forename: Bülent
authors.initials: B
authors.lastname: Sankur
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D003198:Computer Simulation; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008954:Models, Biological; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation / Q000379:methods*