Electro-magneto-encephalography for the three-shell model: numerical implementation via splines for distributed current in spherical geometry
Abstract
The basic inverse problems for the functional imaging techniques of electroencephalography (EEG) and magnetoencephalography (MEG) consist in estimating the neuronal current in the brain from the measurement of the electric potential on the scalp and of the magnetic field outside the head. Here we present a rigorous derivation of the relevant formulae for a three-shell spherical model in the case of independent as well as simultaneous MEG and EEG measurements. Furthermore, we introduce an explicit and stable technique for the numerical implementation of these formulae via splines. Numerical examples are presented using the locations and the normal unit vectors of the real 102 magnetometers and 70 electrodes of the Elekta Neuromag (R) system. These results may have useful implications for the interpretation of the reconstructions obtained via the existing approaches.
- Publication:
-
Inverse Problems
- Pub Date:
- March 2012
- DOI:
- 10.1088/0266-5611/28/3/035009
- Bibcode:
- 2012InvPr..28c5009F