2025/02/24 by Schwarz, Eva, Durisin, Martin, Stadler, Beate
#Medicine and health
paper · doi:10.3205/zaud000065
Research question: A hearing implant is intended to enable people who are deaf or severely hard of hearing to understand speech again. While the cochlear implant (CI) fulfils the function of recognizing sound generally for a large number of CI patients, questions remain about the more detailed aspects of hearing. For successful communication it is also important to be able to perceive speech qualities beyond simply sound detection, however, the CI is limited in its technical ability to transmit certain acoustic signals. In order for CI users to be able to recognize voices and follow conversation, they must be able to distinguish between talkers and their voices in conversational situations. Up to now, studies on talkers’ discrimination by CI users have mainly studied the sensitivity to the distinction between female and male voices. The perception of the formant frequencies of the voice (timbre), which is dependent on the length of the vocal tract, has been mostly unexamined until now. In our study, we investigated the extent to which CI users were able to differentiate between talkers based on individual speech patterns and vocal characteristics. Methods: In our current study, only female or male talkers were presented to the CI users in two rounds. Three female and three male talkers were selected from the OLLO corpus. The task of the CI users was to decide in an equal-unequal paradigm whether the stimulus pair was spoken by the same or by different talkers. So far, 165 experienced CI users (age: 17–92 years) have taken part in our accompanying study. Result: In our study, the hit rates of correctly matched talkers were approx. 64% for female talkers and approx. 68% for male talkers, each about the chance level of 50%. Using the Wilcoxon signed rank test these results appear statistically significant (p<0.001). Conclusion: CI users are able to differentiate between talkers according to differences in their vocal timbre.