Neuromagnetic field modeling of multiple brain regions producing interictal spikes in human epilepsy.

A method of spatiotemporal analysis, using multiple current dipoles to represent activity in multiple brain regions, was applied to the interpretation of extracranial neuromagnetic fields generated by epileptic spikes in patients with focal seizure disorders. This method permitted the identification and approximate localization of cellular currents within single and multiple brain regions engaged over the entire duration of the human epileptic spike complex. These results suggest that spatially and temporally overlapping electrical currents in human epileptic cortex may be investigated non-invasively in the magnetoencephalogram if appropriate physical models are applied.

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