A model for predicting localization performance in cochlear implant users


Mathematical models can be very useful for understanding complicated systems, and for testing algorithms through simulation that would be difficult or expensive to implement. This paper describes the proposal for a model that would simulate the sound localization performance of profoundly hearing-impaired persons using bilateral cochlear implants (CIs). The expectation is that this model could be used as a tool that could prove useful in developing new signal processing algorithms for neural encoding strategies. The head related transfer function (HRTF) is a critical component of this model, and provides the base characteristics of head shadow, torso and pinna effects. This defines the temporal, intensity and spectral cues that are important to sound localization. This model was first developed to simulate normal hearing persons and validated against published literature on HRTFs and localization. The model was then further developed to account for the differences in the signal pathway of the CI user due to sound processing effects, and the microphone location versus ear canal acoustics. Finally, the localization error calculated from the model for CI users was compared to published localization data obtained from this population.

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Miller, D. and Matin, M. (2013) A model for predicting localization performance in cochlear implant users. World Journal of Neuroscience, 3, 136-141. doi: 10.4236/wjns.2013.33017.

Conflicts of Interest

The authors declare no conflicts of interest.


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