Beamforming methods

Authors: Hui-Ling Chan

The estimation of source distribtion is an important step to understand the brain activity from EEG and MEG data. Dipole fitting, minimum norm estimation, and beamformer are three commonly used methods. It has been proved that beamforming methods provide good spatial resolution. This tutorial will show how to apply beamforming methods to MEG data and obtain the statistic map of source activation.

We are going to use the protocol TutorialRaw created in the previous tutorial ?Epoching and Averaging. If you have not followed this tutorial yet, please do it now.

Introduction

Beamfoming methods scan each target voxel/vertex position r to estimate a spatial filter

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which outputs the source activity y

Spatial filter

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Section 2

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Linearly-constrained minimum variance beamformer (LCMV)

Section 1

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Section 2

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Maximum constrast beamformer (MCB)

Section 1

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Section 2

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Beamformer-based correlation/coherence imaging

Dynamic imaging of coherent sources (DICS)

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Spatiotemporal imaging of linearly-related source components (SILSC)

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