Enhancing the Interaural Time Difference of Bilateral Cochlear Implants with the Temporal Limits Encoder

Yangyang Wan, Huali Zhou, Qinglin Meng, Nengheng Zheng


Normal hearing listeners mainly use interaural time differences (ITDs) and interaural level differences (ILDs) to localize sound sources in the horizontal plane. Listeners with bilateral cochlear implants (CIs), however, have poor sensitivity to ITDs which significantly limits their spatial hearing capabilities. Most CI signal processing strategies, such as the continuous interleaved sampling (CIS) strategy, are temporal-envelope-based, and the temporal fine structure (TFS), which contains useful cues for ITDs, is discarded. Recently, a temporal limits encoder (TLE) CI strategy was proposed to implicitly introduce the TFS while preserving the temporal envelope. It has demonstrated benefits in unilateral CI simulations in tasks including speech-in-noise understanding and pitch perception. This study investigates whether the ITD cues could be enhanced by a bilateral TLE strategy. Identification of five ITDs respectively associated with five sound source directions was tested with vocoded speech stimuli to compare the performance of the bilateral TLE and CIS strategies. Results show that the bilateral TLE has better overall performance than the bilateral CIS. This finding suggests that the bilateral TLE is promising in providing enhanced ITD cues for bilateral CI users.


 DOI: 10.21437/Interspeech.2020-2507

Cite as: Wan, Y., Zhou, H., Meng, Q., Zheng, N. (2020) Enhancing the Interaural Time Difference of Bilateral Cochlear Implants with the Temporal Limits Encoder. Proc. Interspeech 2020, 2502-2506, DOI: 10.21437/Interspeech.2020-2507.


@inproceedings{Wan2020,
  author={Yangyang Wan and Huali Zhou and Qinglin Meng and Nengheng Zheng},
  title={{Enhancing the Interaural Time Difference of Bilateral Cochlear Implants with the Temporal Limits Encoder}},
  year=2020,
  booktitle={Proc. Interspeech 2020},
  pages={2502--2506},
  doi={10.21437/Interspeech.2020-2507},
  url={http://dx.doi.org/10.21437/Interspeech.2020-2507}
}