The Annals of Applied Statistics

A two-way regularization method for MEG source reconstruction

Tian Siva Tian, Jianhua Z. Huang, Haipeng Shen, and Zhimin Li

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The MEG inverse problem refers to the reconstruction of the neural activity of the brain from magnetoencephalography (MEG) measurements. We propose a two-way regularization (TWR) method to solve the MEG inverse problem under the assumptions that only a small number of locations in space are responsible for the measured signals (focality), and each source time course is smooth in time (smoothness). The focality and smoothness of the reconstructed signals are ensured respectively by imposing a sparsity-inducing penalty and a roughness penalty in the data fitting criterion. A two-stage algorithm is developed for fast computation, where a raw estimate of the source time course is obtained in the first stage and then refined in the second stage by the two-way regularization. The proposed method is shown to be effective on both synthetic and real-world examples.

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Ann. Appl. Stat. Volume 6, Number 3 (2012), 1021-1046.

First available in Project Euclid: 31 August 2012

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Inverse problem MEG two-way regularization spatio-temporal


Tian, Tian Siva; Huang, Jianhua Z.; Shen, Haipeng; Li, Zhimin. A two-way regularization method for MEG source reconstruction. Ann. Appl. Stat. 6 (2012), no. 3, 1021--1046. doi:10.1214/11-AOAS531.

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