New Paper: Principles of Within Electrode Current Steering (WECS)

Khadka N, Truong DQ, Bikson, M
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Download: PDF Published in Journal of Medical Devices DOI

Abstract

Within Electrode Current Steering (WECS) is a novel method that enhances reliability and tolerability of tDCS. The underlying assumption of WECS is steering current within electrodes but without altering current distribution in brain target. Through an exemplary case example of a realistic electrode and head geometry (FEM), we demonstrated how current flow in the brain is independent of current steering at the electrode. Three current split cases (even, partially uneven, and fully uneven), keeping total current (1 mA) fixed within the electrodes are tested. At the electrode-assembly interface with the skin, the current density distribution varied only incrementally across conditions (e.g. less than would be expected with even minor changes in electrode assembly or skin properties. There was no difference in the predicted electric filed at the brain target under all three cases. Thus, with such electrode assembly design, current steering to any functional electrode would not significantly increase current density in the skin (enhance tolerability during tDCS).