Voice discrimination in children with cochlear implants

In this study, we investigated the voice discrimination ability of children using cochlear implants (CI) and the factors associated with their voice discrimination ability. The participants were 17 CI children and 20 children with normal hearing. We administered voice discrimination tasks using manipulated speech with fundamental frequency (F0), which is related to voice pitch, and formant frequency, which is related to voice quality, to the participants. The discrimination thresholds of the CI children for the F0 and formant frequency was 1.00 semitone (st) and 1.44st, respectively. Under the condition in which the F0 and formant frequency were combined, the threshold of the CI children was 0.50st, the lower limit value. The results show that the age at of implantation was associated with the discrimination threshold formant frequency, with CI children who were implanted at an earlier age showing better discrimination ability. Speech recognition scores were significantly related to the F0 discrimination threshold and formant frequency discrimination threshold. While previous studies indicated that CI children had difficulties in discriminating voices, this study showed that they were able to discriminate even slight differences in voice. CI children who were implanted at an earlier age tended to discriminate voice quality more easily, and but CI children tended to have difficulties in discriminating the pitch and voice quality when they had a low speech recognition score.