The “Quasi-Uniform” Assumption in Animal and Computational Models of Non-Invasive Electrical Stimulation

Abstract

Transcranial stimulation encompasses all non-invasive brain stimulation techniques where electrical current is generated or induced in the brain for experimental or therapeutic purposes using scalp electrodes or magnetic coils. Each modality (e.g. transcranial current stimulation, cranial electrotherapy stimulation, transcranial magnetic stimulation, electroconvulsive therapy) produces a spatiotemporal pattern of electric current flow in the brain that then determines neurophysiological response. Due to the relatively large separation between electrode/coil and stimulated tissue, the target region is often in the “far-field” of the electric field. Thus, unlike stimulation with implanted electrodes, the gradient of the electric field is limited in the vicinity of the brain target.