Neuroelectromagnetic Source Imaging of Brain Dynamics

  • Rey R. Ramírez
  • David Wipf
  • Sylvain Baillet
Part of the Springer Optimization and Its Applications book series (SOIA, volume 38)


Neuroelectromagnetic source imaging (NSI) is the scientific field devoted to modeling and estimating the spatiotemporal dynamics of the neuronal currents that generate the electric potentials and magnetic fields measured with electromagnetic (EM) recording technologies. Unlike functional magnetic resonance imaging (fMRI), which is indirectly related to neuroelectrical activity through neurovascular coupling [e.g., the blood oxygen level-dependent (BOLD) signal], EM measurements directly relate to the electrical activity of neuronal populations. In the past few decades, researchers have developed a great variety of source estimation techniques that are well informed by anatomy, neurophysiology, and the physics of volume conduction. State-of-the-art approaches can resolve many simultaneously active brain regions and their single trial dynamics and can even reveal the spatial extent of local cortical current flows.


Boundary Element Method Expectation Maximization Dipole Orientation Equivalent Current Dipole Gain Vector 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.MEG Program, Department of NeurologyMedical College of Wisconsin and Froedtert HospitalMilwaukeeUSA
  2. 2.Biomagnetic Imaging LaboratoryUniversity of California San FranciscoSan FranciscoUSA

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