Brain Topography

, Volume 18, Issue 2, pp 101–113 | Cite as

Integrated MEG and fMRI Model: Synthesis and Analysis

  • Abbas Babajani
  • Mohammad-Hossein Nekooei
  • Hamid Soltanian-Zadeh
Original Paper


An integrated model for magnetoencephalography (MEG) and functional Magnetic Resonance Imaging (fMRI) is proposed. In the model, the neural activity is related to the Post Synaptic Potentials (PSPs) which is common link between MEG and fMRI. Each PSP is modeled by the direction and strength of its current flow which are treated as random variables. The overall neural activity in each voxel is used for equivalent current dipole in MEG and as input of extended Balloon model in fMRI. The proposed model shows the possibility of detecting activation by fMRI in a voxel while the voxel is silent for MEG and vice versa. Parameters of the model can illustrate situations like closed field due to non-pyramidal cells, canceling effect of inhibitory PSP on excitatory PSP, and effect of synchronicity. In addition, the model shows that the crosstalk from neural activities of the adjacent voxels in fMRI may result in the detection of activations in these voxels that contain no neural activities. The proposed model is instrumental in evaluating and comparing different analysis methods of MEG and fMRI. It is also useful in characterizing the upcoming combined methods for simultaneous analysis of MEG and fMRI.

Key words:

Functional Magnetic Resonance Imaging (fMRI) Magnetoencephalography (MEG) Extended balloon model Integrated model Post Synaptic Potential (PSP) 


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Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • Abbas Babajani
    • 1
  • Mohammad-Hossein Nekooei
    • 1
  • Hamid Soltanian-Zadeh
    • 1
    • 2
  1. 1.Control and Intelligent Processing Center of Excellence, Electrical and Computer Engineering DepartmentUniversity of TehranTehranIran
  2. 2.Image Analysis Lab., Radiology DepartmentHenry Ford Health SystemDetroitUSA

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