Listeners can make use of voice cues, such as fundamental frequency (F0) and vocal-tract length (VTL), to segregate speech signals from different speakers. Hearing loss and hearing aid use may lead to reduced access to relevant acoustic cues, and in children, perceptual cognitive mechanisms may still be developing, all affecting the perception of speech masked by competing speech. In this study, we assessed sensitivity to F0 and VTL voice cues and perception of speech in the presence of competing speech maskers differing in F0 and VTL in school-age children with hearing aids, taking into account developmental effects.

We measured just-noticeable differences (JNDs) of F0 and VTL cues and speech perception in single-talker speech maskers using the Turkish Child-friendly Coordinate Response Measure (CCRM-tr) in native Turkish speaking school-age children (aged 5-18) with hearing aids and with normal hearing. Stimuli were recorded by female speakers. Single-talker speech maskers were created by concatenating random chunks from the sentence database and manipulating F0 and VTL cues to produce voice differences between the target and masker speaker. The target and masker sentences were presented at different target-to-masker ratios.

Both groups of children show development effects of voice cue sensitivity and speech-on-speech perception as a function of age. The developmental patterns for F0 and VTL JNDs seem to differ. Children with hearing aids seem to catch up with age-typical development around teenage years for F0 JNDs, but not for VTL JNDs. For speech perception in speech maskers, both groups show a benefit of F0 and VTL differences between target and masker speech, but the VTL difference benefit is relatively smaller for the children with hearing aids. Our results show a large variability in children with hearing aids, with some children performing at the level of age-matched children with normal hearing, and others performing lower.

Given the development effects throughout childhood and teenage years, age-matched norm data is essential for the evaluation of speech perception in speech maskers in individual children with hearing aids with respect to their age, and for the adjustment of rehabilitation to fit their needs. The finding that many children with hearing aids perform at age-expected levels demonstrates that hearing aids can provide good compensation for hearing loss for voice cue sensitivity and for speech perception in speech maskers.