POTENTIAL AND CURRENT-DENSITY DISTRIBUTIONS OF CRANIAL ELECTROTHERAPYSTIMULATION (CES) IN A 4-CONCENTRIC-SPHERES MODEL

Cranial electrotherapy stimulation (CES) has been successfully used fo r treatment of many psychiatric diseases, Its noninvasive nature is it s major advantage over other forms of treatments such as drugs, It is postulated that the low electric current of CES causes the release of neurotransmitters. However, the current pathways have not been extensi vely investigated, In the following paper, analytical and numerical me thods are used to determine the distribution of potential and current density in a four zone concentric spheres model of the human head when excited by two electrodes diametrically opposite to each other, Becau se of the azimuthal symmetry, which is assumed in this study, a two-di mensional (2-D) finite difference approximation is derived in the sphe rical grid, The current density distribution is projected around the c enter of the model, where the thalamus is modeled as a concentric sphe re, All dimensions and electrical properties of the model are adapted from clinical data. Results of this simulation indicate that, in contr ast to previous beliefs, a small fraction of the CES current does reac hes the thalamic area and may facilitate the release of neurotransmitt ers.