Influence of Test Condition on Speech Perception With Electric-Acoustic Stimulation

The goal of this work was to better understand speech perception for cochlear implant (CI) users with bilateral residual hearing, including consideration of effects related to listening conditions and test measures. Of interest was the role of acoustic hearing for speech perception in a complex background, the role of listening experience for CI-alone conditions, and whether performance with electric-acoustic stimulation (EAS) was improved by a contralateral hearing aid (HA).

Eleven subjects provided data on Consonant-Nucleus-Consonant (CNC; Peterson & Lehiste, 1962) words in quiet, City University of New York (CUNY; Boothroyd, Hanin, & Hnath, 1985) sentences in steady noise, and Bamford-Kowal-Bench (Bench, Kowal, & Bamford, 1979) sentences in multitalker babble. Listening conditions included: CI with a full-frequency map, CI with a truncated-frequency map, EAS, and EAS+HA (EAS plus contralateral HA). Sounds were presented at 0° azimuth.

For CNC words and CUNY sentences, performance was better with the truncated-frequency than the full-frequency map, and performance with EAS was better than for either CI-alone condition. For Bench-Kowal-Bamford sentences, EAS+HA was better than EAS.

As demonstrated previously, performance was better in the EAS condition than either CI-alone condition. Better performance in the truncated-frequency than full-frequency CI-alone condition suggests that listening experience may be important. A contralateral HA improved performance over unilateral EAS under some conditions.