Performance of an MEG Adaptive-Beamformer Source Reconstruction Technique in the Presence of Additive Low-Rank Interference

Kensuke Sekihara, Srikantan S. Nagarajan, David Poeppel, Alec Marantz

Research output: Contribution to journalArticlepeer-review

Abstract

The influence of external interference on neuromagnetic source reconstruction by adaptive beamformer techniques was investigated. In our analysis, we assume that the interference has the following two properties: First, it is additive and uncorrelated with brain activity. Second, its temporal behavior can be characterized by a few distinct activities, and as a result, the spatio-temporal matrix of the interference has a few distinctly large singular values. Namely, the interference can be modeled as a low-rank signal. Under these assumptions, our analysis shows that the adaptive beamformer techniques are insensitive to interference when its spatial singular vectors are so different from a lead field vector of a brain source that the generalized cosine between these two vectors is much smaller than unity. Four types of numerical examples verifying this conclusion are presented.

Original languageEnglish (US)
Pages (from-to)90-99
Number of pages10
JournalIEEE Transactions on Biomedical Engineering
Volume51
Issue number1
DOIs
StatePublished - Jan 2004

Keywords

  • Adaptive beamformer
  • Biomagnetism
  • Functional neuroimaging
  • MEG inverse problems
  • Magnetoencephalography
  • Neuromagnetic signal processing

ASJC Scopus subject areas

  • Biomedical Engineering

Fingerprint Dive into the research topics of 'Performance of an MEG Adaptive-Beamformer Source Reconstruction Technique in the Presence of Additive Low-Rank Interference'. Together they form a unique fingerprint.

Cite this