title: Current steering and current focusing with a high-density intracochlear electrode array.
abstract: Creating high-resolution or high-density, intra-cochlear electrode arrays may significantly improve quality of hearing for cochlear implant recipients. Through focused activation of neural populations such arrays may better exploit the cochlea's frequency-to-place mapping, thereby improving sound perception. Contemporary electrode arrays approach high-density stimulation by employing multi-polar stimulation techniques such as current steering and current focusing. In our procedure we compared an advanced high-density array with contemporary arrays employing these strategies. We examined focused stimulation of auditory neurons using an activating function and a neural firing probability model that together enable a first-order estimation of an auditory nerve fiber's response to electrical stimulation. The results revealed that simple monopolar stimulation with a high-density array is more localized than current steering with a contemporary array and requires 25-30% less current. Current focusing with high-density electrodes is more localized than current focusing with a contemporary array; however, a greater amount of current is required. This work illustrates that advanced high-density electrode arrays may provide a low-power, high-resolution alternative to current steering with contemporary cochlear arrays.
authors.affiliation: School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0250, USA.
authors.forename: Jessica D
authors.initials: JD
authors.lastname: Falcone
authors.forename: Pamela T
authors.initials: PT
authors.lastname: Bhatti
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D003051:Cochlea / Q000502:physiology*; D003198:Computer Simulation; D004567:Electrodes, Implanted; D006801:Humans; D008959:Models, Neurological; D015233:Models, Statistical; D011984:Sensory Receptor Cells / Q000502:physiology*