Mental processing comparison between past and future employing a novel EEG analysis based on radiated EM field estimation.

BACKGROUND: The inverse problem solution in the field of ElectroEncephaloGraphy (EEG) analysis has been addressed in the scientific literature for many decades, utilizing either mathematical techniques for measurement fitting or pure ElectroMagnetic (EM) methods involving complex head models for the prediction of the near field.

NEW METHOD: A novel radiated EM field estimation analysis scheme is proposed for EEG analysis, based on the determination of a grid of equivalent distributed EM sources with equal magnetic moments, in order to compute the extrapolated far field. A Pattern Search approach is adopted to minimize the Mean Absolute Relative Error between the EM near field created by the source grid and the EM field extracted by the measurements.

RESULTS: The application of the method on a subject's brain activity recordings in the context of "Protagoras" mental-auditory experiment demonstrates the capability of the proposed scheme to compare the subject's concentration differences between the limit of present and past versus the limit of present and future.

COMPARISON WITH EXISTING METHODS: The proposed method combines features from different existing methods, both in terms of mathematical and EM theory techniques, in order to extend their capabilities and transform the conventional analysis of EEG recordings to a far field radiation basis.

CONCLUSIONS: The treatment of the brain as an equivalent far field radiator can be a useful and promising new perspective to the established analysis of EEG recordings arising from brain activity during mental processing.