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Updated: Jul 12, 2026
09:32
Cortical Source Analysis of High-Density EEG Recordings in Children
Published on: June 30, 2014
Model selection in spatio-temporal electromagnetic source analysis
Lourens J Waldorp1, Hilde M Huizenga, Arye Nehorai
1Department of Psychology, University of Amsterdam, Roetersstraat 15, 1018 WB Amsterdam, The Netherlands. waldorp@psy.uva.nl
IEEE Transactions on Bio-Medical Engineering
|March 12, 2005
Summary
This study extends model selection procedures (MSPs) for electroencephalogram (EEG) and magnetoencephalogram (MEG) data analysis. The Akaike information criterion (AIC) and Wald tests (WA, WL) accurately determine the number of brain sources, with WA identifying active sources over time.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Signal Processing
Background:
- Determining the number of sources in electroencephalogram (EEG) and magnetoencephalogram (MEG) data is crucial for source localization.
- Previous model selection procedures (MSPs) were primarily evaluated in instantaneous analyses.
Purpose of the Study:
- To extend existing MSPs for source number determination to spatio-temporal analyses of EEG and MEG data.
- To compare the performance of various MSPs in accurately identifying the number of neural sources.
Main Methods:
- Extension of established model selection procedures (MSPs) to spatio-temporal analysis.
- Evaluation of residual variance (RV), Akaike information criterion (AIC), Wald test on amplitudes (WA), and Wald test on locations (WL).
Main Results:
- The residual variance (RV) method tends to overestimate the number of sources.
- Akaike information criterion (AIC), Wald test on amplitudes (WA), and Wald test on locations (WL) demonstrated higher accuracy in selecting the correct number of sources.
- The Wald test on amplitudes (WA) uniquely allows for testing source activity at specific time points.
Conclusions:
- Spatio-temporal analysis improves the accuracy of source number determination in EEG and MEG.
- AIC and Wald tests (WA, WL) are recommended for reliable source number estimation.
- WA offers additional temporal information regarding source activation.
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