1. A method for customizing cochlear implant stimulation of a living subject, wherein the cochlear implant comprises an electrode array having a plurality of electrodes implanted in a cochlea of the living subject, comprising the steps of: (a) identifying a spiral ganglion (SG) neural region that is targeted for stimulation and its corresponding modiolar interface and determining a position for each of the plurality of electrodes relative to the SG neural region, wherein each electrode has a distance relative to a closest stimulation point on the SG neural region, and the SG has a characteristic frequency corresponding to each closest stimulation point; (b) constructing a tonotopic map of the modiolar interface to have a tonotopically mapped modiolar interface; (c) determining a geometric relationship between the tonotopically mapped modiolar interface and each of the plurality of electrodes by an electrode distance-vs-frequency curve showing the distance from each frequency mapped region of the SG to each electrode; and (d) configuring one or more electrodes of the electrode array to stimulate a region of the modiolar interface based on the position of the one or more electrodes and their geometric relationship with the tonotopically mapped modiolar interface.