This disclosure relates to methods for modifying neural activity by applying electrical current to a neural tissue, e.g., in a transcranial DC stimulation procedure (tDCS), a transcranial AC stimulation procedure (tACS), a transcranial random noise stimulation procedure (tRNS), a deep brain stimulation procedure (DBS), a transcutaneous electrical nerve stimulation procedure (TENS), or the like. Historically, computed potential, electrical field, and/or current density distributions have been used to select the locations of the electrodes that apply the electrical current. In the present disclosure, a computed charge distribution on the bounding surface of one or more sulci filled with cerebrospinal fluid (CSF) is used in selecting the electrode locations. In one embodiment, the sulcus's bounding surface is divided into pixels and each pixel's charge is determined by the pixel functioning as a sensor for the charges surrounding it, including the charges of other pixels and the charges on the electrodes.
Charge-based methods for modifying neural activity