Inverse solution for time-correlated multiple sources using Beamformer method

Takeshi Kimura, Masahiro Kako, Hiromi Kamiyama, Atsushi Ishiyama, Naoko Kasai, Yutaka Watanabe

    Research output: Contribution to journalArticle

    3 Citations (Scopus)

    Abstract

    The Adaptive Beamformer draws attention as an MEG inverse solution for multiple sources. The method has a drawback that we cannot apply it to the temporally correlated sources. We had developed a method to overcome this drawback. Signal-subspace eigenvectors of an original data-covariance matrix was decomposed by the GA-SA method (the hybrid method of Genetic Algorithm and Simulated Annealing) and a new decorrelated data-covariance matrix was reconstructed. The GA-SA method, however, requires the number of components of the eigenvector as a foreknowledge. In this study, we introduced the minimum-norm method, that requires no foreknowledge, instead of the GA-SA method. We carried out a three-dimensional simulation study using the proposed method, and applied to the auditory evoked response field measured by using the Vectorview system. As a result, multiple sources with time-correlations were successfully estimated.

    Original languageEnglish
    Pages (from-to)417-420
    Number of pages4
    JournalInternational Congress Series
    Volume1300
    DOIs
    Publication statusPublished - 2007 Jun

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    Auditory Evoked Potentials

    Keywords

    • Adaptive Beamformer
    • AEF(Auditory Evoked Field)
    • MEG(Magnetoencephalography)
    • Minimum-norm method
    • Source estimation

    ASJC Scopus subject areas

    • Medicine(all)

    Cite this

    Inverse solution for time-correlated multiple sources using Beamformer method. / Kimura, Takeshi; Kako, Masahiro; Kamiyama, Hiromi; Ishiyama, Atsushi; Kasai, Naoko; Watanabe, Yutaka.

    In: International Congress Series, Vol. 1300, 06.2007, p. 417-420.

    Research output: Contribution to journalArticle

    Kimura, Takeshi ; Kako, Masahiro ; Kamiyama, Hiromi ; Ishiyama, Atsushi ; Kasai, Naoko ; Watanabe, Yutaka. / Inverse solution for time-correlated multiple sources using Beamformer method. In: International Congress Series. 2007 ; Vol. 1300. pp. 417-420.
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    AU - Kasai, Naoko

    AU - Watanabe, Yutaka

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