Spatial Filtering of MEG Signals for User-Specified Spherical Regions

Date

2009-10-01

Author

Özkurt, Tolga Esat
Sun, Mingui
Jia, Wenyan
Sclabassi, Robert J.

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We introduce a spatial filtering method in the spherical harmonics domain for constraining magnetoencephalographic (MEG) multichannel measurements to any user-specified spherical region of interest (ROI) inside the head. The method relies on a linear transformation of the signal space separation inner coefficients that represent the MEG signal generated by sources located inside the head. The spatial filtering is achieved effectively by constructing a spherical harmonics basis vector that is dependent on the center of the targeted ROI and it does not require any discrete division of the headspace into grids like the traditional MEG spatial filtering approaches. The validation and the performance of the method are demonstrated through both simulated and actual bilateral auditory-evoked data experiments.

Subject Keywords

Biomagnetism, inverse problem, magnetoencephalography (MEG), signal space separation (SSS), source localization, spatial filtering, spherical harmonics, SPACE SEPARATION, RESPONSES, EEG

URI

https://hdl.handle.net/11511/97171

Journal

IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING

DOI

https://doi.org/10.1109/tbme.2009.2024760

Collections

Graduate School of Informatics, Article

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Citation Formats

T. E. Özkurt, M. Sun, W. Jia, and R. J. Sclabassi, “Spatial Filtering of MEG Signals for User-Specified Spherical Regions,” IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, vol. 56, no. 10, pp. 2429–2438, 2009, Accessed: 00, 2022. [Online]. Available: https://hdl.handle.net/11511/97171.