On electrical potentials observed at a distance from intracranial electrode contacts.

摘要

I read with interest the paper of Zaveri et al. (2009), which argued for the position that an electrical potential at a distance cannot be observed by an intracranial electrode contact. I cannot attempt to refute the mathematical arguments explaining the magnitude of electrical field intensity due to a point charge, and indeed these arguments seem to align well with everyday clinical observations of electrical potentials generated by small fields in the brain. However, I am not so sure that this line of argument holds for electrical potentials generated by large fields in the brain -the size of the field may actually matter here. Zaveri et al. (2009) state that their position holds equally well for single point charges and spatially extended electrical fields, but I believe this requires further consideration. Rather than (and incapable of) providing a mathematical counter argument, 1 would like to present for consideration instead a series of EEG pictures showing what an intracranial electrode contact observes at the time of a large distant electrical discharge in the brain, because the pictures do seem to show adjacent intracranial electrode contacts observing synchronously, at a distance, volume conducted cerebral electrical potentials.