Perception of Voice Cues and Speech-in-Speech by Children with Prelingual Single-Sided Deafness and a Cochlear Implant

Authors: Tine Arras1, Laura Rachman2, Astrid van Wieringen1, Deniz Başkent2

1KU Leuven
2University Medical Center Groningen

Background: Voice cues, such as fundamental frequency (F0) and vocal tract length (VTL), help listeners identify the speaker’s gender, perceive linguistic and emotional prosody, and segregate competing talkers. Postlingually deaf adult cochlear implant (CI) users seem to struggle with perceiving and using voice cues, especially VTL. Early implanted pediatric CI users, in contrast, perceive and use both voice cues better than CI adults, and in patterns similar to their peers with normal hearing (NH). In an attempt to bridge the gap between both groups, we investigated the perception and use of voice cues in nine children with prelingual single-sided deafness (SSD) who received their CI at an early age (SSD+CI). These children have access to bilateral auditory information and received their CI at an early age, similar to CI children. They may also have dominant acoustic representations, similar to postlingually deaf CI adults.

Methods: The study consisted of three experiments: F0 and VTL discrimination, voice gender categorization, and speech-masked speech perception. In each experiment, the results of the SSD+CI group are compared to children and adults with CIs and with NH.

Results: Overall, the SSD+CI children had poorer VTL detection thresholds with their CI compared to their NH ear, while their F0 perception was similar across ears. They relied more heavily on F0 cues than on VTL cues for voice gender categorization, with cue weighting patterns comparable to those of CI adults. In contrast to CI children, and similar to CI adults, the SSD+CI children showed limited speech perception benefit based on F0 and VTL differences between the target and masker speaker.

Conclusions: Altogether, the SSD+CI children’s results seem to fall in between the results of CI children and CI adults. Perhaps a combination of childhood neuroplasticity, limited experience with relying only on the CI, and a dominant acoustic representation of voice gender might explain these findings.