Truncated RAP-MUSIC (TRAP-MUSIC) for MEG and EEG source localization

Thumbnail Image

Access rights

openAccess
publishedVersion

URL

Journal Title

Journal ISSN

Volume Title

A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä

Date

2018-02-15

Major/Subject

Mcode

Degree programme

Language

en

Pages

11
73-83

Series

NeuroImage, Volume 167

Abstract

Electrically active brain regions can be located applying MUltiple SIgnal Classification (MUSIC) on magneto- or electroencephalographic (MEG; EEG) data. We introduce a new MUSIC method, called truncated recursively-applied-and-projected MUSIC (TRAP-MUSIC). It corrects a hidden deficiency of the conventional RAP-MUSIC algorithm, which prevents estimation of the true number of brain-signal sources accurately. The correction is done by applying a sequential dimension reduction to the signal-subspace projection. We show that TRAP-MUSIC significantly improves the performance of MUSIC-type localization; in particular, it successfully and robustly locates active brain regions and estimates their number. We compare TRAP-MUSIC and RAP-MUSIC in simulations with varying key parameters, e.g., signal-to-noise ratio, correlation between source time-courses, and initial estimate for the dimension of the signal space. In addition, we validate TRAP-MUSIC with measured MEG data. We suggest that with the proposed TRAP-MUSIC method, MUSIC-type localization could become more reliable and suitable for various online and offline MEG and EEG applications.

Description

Keywords

EEG, Electroencephalography, Inverse methods, Magnetoencephalography, MEG, Multiple sources, Source localization, Neurology, Cognitive Neuroscience, 3112 Neurosciences

Other note

Citation

Mäkelä , N , Stenroos , M , Sarvas , J & Ilmoniemi , R J 2018 , ' Truncated RAP-MUSIC (TRAP-MUSIC) for MEG and EEG source localization ' , NeuroImage , vol. 167 , pp. 73-83 . https://doi.org/10.1016/j.neuroimage.2017.11.013