Abstract: An array of electrodes, suitable for use as an auditory prosthesis, and a method for fabricating such an array, are disclosed. The array includes an electrode body formed from an electrically insulating flexible material, preferably at least one annulus of an electrically insulating flexible material which is formed separately from the body and adhered thereto, at least one electrode positioned concentrically about each of the at least one annulus or electrode body, with the surface of each electrode being recessed and being exposed.

Abstract: The invention provides an array of electrodes suitable for use as an auditory prosthesis. The array comprises a carrier member formed from electrically insulating flexible material, having a surface and a core, the carrier member including at least a pair of electrodes molded therein, the electrodes comprising a length of contact material formed in a semi-circular shape, having a convex contact surface and a locking portion defining an internal space. The electrode is molded in the carriers so that the convex contact surface of the electrode is preferably flush with the carrier member surface. The locking portion of the electrode is molded into the core of the carrier member in the electrode connected to a lead wire which is molded in the core of the carrier member. The invention further provides a method for fabricating such an array of bipolar electrodes.

Abstract: A method for determining absolute current density through an implanted electrode measures the fundamental and harmonic components of an electrical current passing through the electrode and estimates the absolute current density from the ratio between the magnitude of the electrical current measured at one of the harmonics on the fundamental frequency. Another method of the invention applies a wideband noise input voltage to the electrode under investigation and measures the spectrum of the input voltage and output current to determine a first transfer function. A second transfer function representing an increase magnitude of wideband noise input voltage is also obtained. A difference transfer function is computed and used to determine absolute current density through the electrode. The methods may be practiced non-invasively.