| Zugriffsnummer | 14730 |
| Dokumenttyp | Zeitschriftenartikel |
| Sprache | Englisch |
| Titel | Cardiac artifact subspace identification and elimination in cognitive MEG data using time-delayed decorrelation |
| Autor(in); Institution |
Sander-Thömmes, Tilmann; 8.21, Bioelektrizität und -magnetismus, PTB-Berlin
Wübbeler, Gerd; 8.21, Bioelektrizität und -magnetismus, PTB-Berlin
Lueschow, A.; Neurophysics Group, Universitätsklinikum Benjamin Franklin, FU Berlin, GERMANY
Curio, Gabriel; Neurophysics Group, Universitätsklinikum Benjamin Franklin, FU Berlin, GERMANY
Trahms, Lutz; 8.21, Bioelektrizität und -magnetismus, PTB-Berlin
|
| Quelle/Jahr | IEEE Transactions on Biomedical Engineering: 49 (2002), 4, 345 - 354 |
| ISSN | 0018-9294 |
| DOI | |
| Verlag | New York: IEEE |
| Freie Schlagworte | Magnetoencephalography ; independent component analysis ; temporal decorrelation ; cardiac artifact ; alpha rhythm ; superconducting quantum interference device ; SQUID ; visually evoked fields |
| Zusammenfassung | To reduce physiological artifacts in MEG and EEG recordings a number of methods have been applied in the past such as Principal Component Analysis, Signal Space Projection, regression using secondary information and Independent omponent Analysis. This method has become popular as it does not have constraints such as orthogonality between artifact and signal or the need for a priori information. Applying the time-delayed decorrelation algorithm to raw data from a visual stimulation MEG experiment we show that several of the independent components can be attributed to the cardiac artifact. Calculating an average cardiac activity shows that physiologically different excitation states of the heart produce similar field distributions in the MEG sensor system. This is equivalent to differing spectral properties of cardiac field distributions in the raw data. As a consequence the algorithm combines e.g. the R-peak and the T-wave of the cardiac cycle into a single component and the one to one assignment of each independent component with a physiological source is not justified in this case. To improve the signal quality of visually evoked fields the multi-dimensional cardiac artifact subspace is suppressed from the data. To assess the preservation of the evoked signal after artifact suppression a geometrical and a temporal measure are introduced. The suppression of cardiac and alpha wave artifacts allows in our experimental setting to reduce the number of epochs to one half while preserving the visually evoked signal. |
Zitierung
Sander-Thömmes, T., Wübbeler, G., Lueschow, A., Curio, G., & Trahms, L. (2002). Cardiac artifact subspace identification and elimination in cognitive MEG data using time-delayed decorrelation. IEEE Transactions on Biomedical Engineering, 49(4), 345–354. https://doi.org/10.1109/10.991162