Reliable evaluation of functional connectivity and graph theory measures in source-level EEG: How many electrodes are enough?
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A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
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en
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16
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Clinical Neurophysiology, Volume 150, pp. 1-16
Abstract
Objective: Using EEG to characterise functional brain networks through graph theory has gained significant interest in clinical and basic research. However, the minimal requirements for reliable measures remain largely unaddressed. Here, we examined functional connectivity estimates and graph theory metrics obtained from EEG with varying electrode densities. Methods: EEG was recorded with 128 electrodes in 33 participants. The high-density EEG data were subsequently subsampled into three sparser montages (64, 32, and 19 electrodes). Four inverse solutions, four measures of functional connectivity, and five graph theory metrics were tested. Results: The correlation between the results obtained with 128-electrode and the subsampled montages decreased as a function of the number of electrodes. As a result of decreased electrode density, the network metrics became skewed: mean network strength and clustering coefficient were overestimated, while characteristic path length was underestimated. Conclusions: Several graph theory metrics were altered when electrode density was reduced. Our results suggest that, for optimal balance between resource demand and result precision, a minimum of 64 electrodes should be utilised when graph theory metrics are used to characterise functional brain networks in source-reconstructed EEG data. Significance: Characterisation of functional brain networks derived from low-density EEG warrants careful consideration.Description
Funding Information: This project is funded by the South-Eastern Norway Regional Health Authority, project number 2016033, and is in partnership with the Centre for Digital Life Norway, supported by the Research Council of Norway’s grant 248810. The authors gratefully acknowledge the contributions of Aksel Erichsen and Vebjørn Andersson to the data collection phase of this study. Publisher Copyright: © 2023 International Federation of Clinical Neurophysiology
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Hatlestad-Hall, C, Bruña, R, Liljeström, M, Renvall, H, Heuser, K, Taubøll, E, Maestú, F & Haraldsen, I H 2023, 'Reliable evaluation of functional connectivity and graph theory measures in source-level EEG: How many electrodes are enough?', Clinical Neurophysiology, vol. 150, pp. 1-16. https://doi.org/10.1016/j.clinph.2023.03.002