Localizing Brain Activity from Multiple Distinct Sources via EEG

Abstract EN

An important question arousing in the framework of electroencephalography (EEG) is the possibility to recognize, by means of a recorded surface potential, the number of activated areas in the brain.

In the present paper, employing a homogeneous spherical conductor serving as an approximation of the brain, we provide a criterion which determines whether the measured surface potential is evoked by a single or multiple localized neuronal excitations.

We show that the uniqueness of the inverse problem for a single dipole is closely connected with attaining certain relations connecting the measured data.

Further, we present the necessary and sufficient conditions which decide whether the collected data originates from a single dipole or from numerous dipoles.

In the case where the EEG data arouses from multiple parallel dipoles, an isolation of the source is, in general, not possible.