Modeling and source localization of MEG activities

Shoogo Ueno, Keiji Iramina

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

During the past decade, substantial advances in the understanding of the functional organization of the human brain have been made through the technique of MEG topographic mapping. Most of these investigations were concerned with the estimation and localization of sources which were modeled as single current dipoles positioned in a semi-infinite volume conductor with homogeneous conductivity. However, the sources in the brain are complex, and the head as a volume conductor consists of different materials with different electrical conductivities. The influence of these inhomogeneities on the MEG topography is studied by a computer simulation, modeling the sources as single or multiple dipoles located in inhomogeneous volume conductors. The computer simulation suggests some important aspects in estimation of source localization. The sources of MEG activities in human subject during sleep are also studied. A comparison of simulated MEG topographic patterns with measured data suggests that the sources of K-complexes can be modeled by two current dipoles. Sources for delta waves are analyzed by the FFT technique. The results show that the frequency distributions are different for delta waves measured by MEG and EEG techniques, leading us to conclude that at least two different sources are present. The MEG measurements have an advantage to provide important information concerning brain function which cannot be obtained using the EEG measurements.

Original languageEnglish
Pages (from-to)151-165
Number of pages15
JournalBrain Topography
Volume3
Issue number1
DOIs
Publication statusPublished - Sep 1 1990

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Computer Simulation
Electroencephalography
Brain
Electric Conductivity
Information Storage and Retrieval
Human Activities
Sleep
Head

All Science Journal Classification (ASJC) codes

  • Anatomy
  • Radiological and Ultrasound Technology
  • Radiology Nuclear Medicine and imaging
  • Neurology
  • Clinical Neurology

Cite this

Modeling and source localization of MEG activities. / Ueno, Shoogo; Iramina, Keiji.

In: Brain Topography, Vol. 3, No. 1, 01.09.1990, p. 151-165.

Research output: Contribution to journalArticle

Ueno, Shoogo ; Iramina, Keiji. / Modeling and source localization of MEG activities. In: Brain Topography. 1990 ; Vol. 3, No. 1. pp. 151-165.
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