[Speaker discrimination in cochlear implant users]

Although the word and sentence recognition skills of cochlear implant (CI) users have been studied extensively, little is known about their ability to distinguish between individuals on the basis of voice, an important skill for social communication.

Speech material from the Oldenburg Logatome Corpus (OLLO) was used to build a set of 120 logatome pairs spoken by 15 male and 15 female speakers, with no overlap of the fundamental frequencies of the two groups of speakers. Each pair contained two different logatomes. For half of the pairs, the two logatomes were spoken by the same speaker, for the other half they were spoken by different speakers. Using a same-different paradigm, 13 adult normal-hearing listeners and 13 adult post-lingually deafened CI users were asked whether the pair of different logatomes were spoken by the same or by different speakers.

Mean speaker discrimination score for the CI users was 74.6 % correct and for the normal-hearing listeners 89.6 % correct. A significant influence of voice gender on speaker discrimination score was found in CI users and in normal hearing listeners.

The results of the CI users were significantly above the level of chance and no ceiling effect was observed for the normal-hearing listeners, i. e., the presented set of logatome pairs from the OLLO seems to be very well suited to speaker discrimination experiments in CI users and quantitative comparison to normal-hearing listeners. CI users are able to discriminate between speakers but their performance is slightly worse than that of normal-hearing listeners.