Source Separation and Higher-Order Causal Analysis of MEG and EEG
2010
Conference Paper
ei
Separation of the sources and analysis of their connectivity have been an important topic in EEG/MEG analysis. To solve this problem in an automatic manner, we propose a twolayer model, in which the sources are conditionally uncorrelated from each other, but not independent; the dependence is caused by the causality in their time-varying variances (envelopes). The model is identified in two steps. We first propose a new source separation technique which takes into account the autocorrelations (which may be time-varying) and time-varying variances of the sources. The causality in the envelopes is then discovered by exploiting a special kind of multivariate GARCH (generalized autoregressive conditional heteroscedasticity) model. The resulting causal diagram gives the effective connectivity between the separated sources; in our experimental results on MEG data, sources with similar functions are grouped together, with negative influences between groups, and the groups are connected via some interesting sources.
Author(s): | Zhang, K. and Hyvärinen, A. |
Journal: | Uncertainty in Artificial Intelligence: Proceedings of the Twenty-Sixth Conference (UAI 2010) |
Pages: | 709-716 |
Year: | 2010 |
Month: | July |
Day: | 0 |
Editors: | Gr{\"u}nwald, P. , P. Spirtes |
Publisher: | AUAI Press |
Department(s): | Empirische Inferenz |
Bibtex Type: | Conference Paper (inproceedings) |
Event Name: | 26th Conference on Uncertainty in Artificial Intelligence (UAI 2010) |
Event Place: | Catalina Island, CA, USA |
Address: | Corvallis, OR, USA |
Digital: | 0 |
ISBN: | 978-0-9749039-6-5 |
Language: | en |
Organization: | Max-Planck-Gesellschaft |
School: | Biologische Kybernetik |
Links: |
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BibTex @inproceedings{6630, title = {Source Separation and Higher-Order Causal Analysis of MEG and EEG}, author = {Zhang, K. and Hyv{\"a}rinen, A.}, journal = {Uncertainty in Artificial Intelligence: Proceedings of the Twenty-Sixth Conference (UAI 2010)}, pages = {709-716}, editors = {Gr{\"u}nwald, P. , P. Spirtes}, publisher = {AUAI Press}, organization = {Max-Planck-Gesellschaft}, school = {Biologische Kybernetik}, address = {Corvallis, OR, USA}, month = jul, year = {2010}, doi = {}, month_numeric = {7} } |