The effect of electrode shapes at tDCS in study of stroke patients

The shape of electrodes is one of the important factors in tDCS
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. The existence of corners and edges in structures of electrodes has important effects in producing of the electric field stimulation in the brain. In this paper, by designing some types of electrode structures using regular polygons and semi-fractals, the electric field distribution in all layers of the head is measured and is studied. For this aim, using FEM
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, one MRI
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data from stroke patients is simulated. The results of the tDCS show the sharper corners have more effect in electric field distribution. Also, the direction of the current density is studied. The results show, if the structure of the electrodes has corners and edges so, the direction of the current density of the tDCS is not uniform.