Abstract
We have developed a method that incorporates the time-frequency characteristics of neural sources into magnetoencephalographic (MEG) source estimation. This method, referred to as the time-frequency multiple-signal- classification algorithm, allows the locations of neural sources to be estimated from any time-frequency region of interest. In this paper, we formulate the method based on the most general form of the quadratic time- frequency representations. We then apply it to two kinds of nonstationary MEG data: gamma-band (frequency range between 30-100 Hz) auditory activity data and spontaneous MEG data. Our method successfully detected the gamma-band source slightly medial to the N1m source location. The method was able to selectively localize sources for alpha-rhythm bursts at different locations. It also detected the mu-rhythm source from the alpha-rhythm-dominant MEG data that was measured with the subject's eyes closed. The results of these applications validate the effectiveness of the time-frequency MUSIC algorithm for selectively localizing sources having different time-frequency signatures.
Original language | English (US) |
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Pages (from-to) | 642-653 |
Number of pages | 12 |
Journal | IEEE Transactions on Biomedical Engineering |
Volume | 47 |
Issue number | 5 |
DOIs | |
State | Published - 2000 |
Keywords
- Biomagnetism
- Biomedical signal processing
- Functional brain imaging
- Inverse problems
- Time-frequency analysis
ASJC Scopus subject areas
- Biomedical Engineering