Brain Topography

, Volume 25, Issue 2, pp 157–166 | Cite as

Source Connectivity Analysis from MEG and its Application to Epilepsy Source Localization

  • Yakang Dai
  • Wenbo Zhang
  • Deanna L. Dickens
  • Bin HeEmail author
Original Paper


We report an approach to perform source connectivity analysis from MEG, and initially evaluate this approach to interictal MEG to localize epileptogenic foci and analyze interictal discharge propagations in patients with medically intractable epilepsy. Cortical activities were reconstructed from MEG using individual realistic geometry boundary element method head models. Directional connectivity among cortical regions of interest was then estimated using directed transfer function. The MEG source connectivity analysis method was implemented in the eConnectome software, which is open-source and freely available at As an initial evaluation, the method was applied to study MEG interictal spikes from five epilepsy patients. Estimated primary epileptiform sources were consistent with surgically resected regions, suggesting the feasibility of using cortical source connectivity analysis from interictal MEG for potential localization of epileptiform activities.


Epilepsy MEG Source imaging Functional connectivity Directed transfer function eConnectome 



This work was supported in part by NIH/NIBIB under grants RO1EB006433 and RO1EB007920 to Bin He.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Yakang Dai
    • 1
  • Wenbo Zhang
    • 2
  • Deanna L. Dickens
    • 2
  • Bin He
    • 1
    Email author
  1. 1.Department of Biomedical EngineeringUniversity of MinnesotaMinneapolisUSA
  2. 2.Minnesota Epilepsy GroupJohn Nasseff Neuroscience Center at United HospitalSaint PaulUSA

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