Polarity Sensitivity as a Potential Correlate of Neural Degeneration in Cochlear Implant Users

Polarity Sensitivity as a Potential Correlate of Neural Degeneration in Cochlear Implant Users: AbstractCochlear implant (CI) performance varies dramatically between subjects. Although the causes of this variability remain unclear, the electrode-neuron interface is thought to play an important role. Here we evaluate the contribution of two parameters of this interface on the perception of CI listeners: the electrode-to-modiolar wall distance (EMD), estimated from cone-beam computed tomography (CT) scans, and a measure of neural health. Since there is no objective way to quantify neural health in CI users, we measure stimulus polarity sensitivity, which is assumed to be related to neural degeneration, and investigate whether it also correlates with subjects ’ performance in speech recognition and spectro-temporal modulation detection tasks. Detection thresholds were measured in fift...