Delis, I., Onken, A., Schyns, P. G. , Panzen, S. and Philiastides, M. (2016) Space-by-time non-negative matrix factorization for single-trial decoding of M/EEG activity. NeuroImage, 133, pp. 504-515. (doi: 10.1016/j.neuroimage.2016.03.043) (PMID:27033682) (PMCID:PMC4907687)
|
Text
118013.pdf - Published Version Available under License Creative Commons Attribution. 1MB |
Abstract
We develop a novel methodology for the single-trial analysis of multichannel time-varying neuroimaging signals. We introduce the space-by-time M/EEG decomposition, based on Non-negative Matrix Factorization (NMF), which describes single-trial M/EEG signals using a set of non-negative spatial and temporal components that are linearly combined with signed scalar activation coefficients. We illustrate the effectiveness of the proposed approach on an EEG dataset recorded during the performance of a visual categorization task. Our method extracts three temporal and two spatial functional components achieving a compact yet full representation of the underlying structure, which validates and summarizes succinctly results from previous studies. Furthermore, we introduce a decoding analysis that allows determining the distinct functional role of each component and relating them to experimental conditions and task parameters. In particular, we demonstrate that the presented stimulus and the task difficulty of each trial can be reliably decoded using specific combinations of components from the identified space-by-time representation. When comparing with a sliding-window linear discriminant algorithm, we show that our approach yields more robust decoding performance across participants. Overall, our findings suggest that the proposed space-by-time decomposition is a meaningful low-dimensional representation that carries the relevant information of single-trial M/EEG signals.
| Item Type: | Articles |
|---|---|
| Status: | Published |
| Refereed: | Yes |
| Glasgow Author(s) Enlighten ID: | Delis, Dr Ioannis and Schyns, Professor Philippe and Philiastides, Professor Marios |
| Authors: | Delis, I., Onken, A., Schyns, P. G., Panzen, S., and Philiastides, M. |
| College/School: | College of Medical Veterinary and Life Sciences > School of Psychology & Neuroscience |
| Journal Name: | NeuroImage |
| Publisher: | Elsevier |
| ISSN: | 1053-8119 |
| ISSN (Online): | 1095-9572 |
| Published Online: | 24 March 2016 |
| Copyright Holders: | Copyright © 2016 The Authors |
| First Published: | First published in Neuroimage 133:504-515 |
| Publisher Policy: | Reproduced under a Creative Commons License |
University Staff: Request a correction | Enlighten Editors: Update this record
Funder and Project Information
Funder and Project Information