Relaxing cochlear implant electrode design constraints using high pulse rate stimulation

Inferior colliculus units have a significantly lower stimulus threshold when driven with a cochlear implant using bipolar stimuli at high (2 k pulses/s) compared to low (125 pulses/s) pulse rates. At high pulse rates temporal summation is used to explain this threshold shift. A background “spontaneous” stimulus strategy is described here which has the potential to lower further stimulus threshold current. Lower thresholds and smaller stimulus currents may allow for the use of smaller cochlear implant stimulus electrodes and potentially more channels of stimulation within a given cochlea region