The study was a within-subjects design with 21 CI users completing pitch discrimination measures using pure, complex, and modulated tones. Stimulus manipulations were used to test whether CI users have better pitch discrimination for low-pass compared with high-pass filtered harmonic complexes, and to test whether they have better pitch discrimination when provided a covarying place cue when listening to amplitude-modulated tones.
Averaged across conditions, participants had better pitch discrimination for pure tones compared with either complex or amplitude-modulated tones. Participants had better pitch discrimination for low-pass compared with high-pass harmonic complexes and better pitch discrimination for amplitude-modulated tones when provided a covarying place cue.
CI users integrate place and rate cues across the ecologically essential pitch range between 110 and 440 Hz. We interpret the observed better pitch discrimination for low-pass compared with high-pass filtered harmonics complexes, and for amplitude-modulated tones when provided a covarying place cue, as evidence for the importance of providing place-of-excitation cues for fundamental frequencies below 440 Hz. Discussion considers how such encoding could be implemented with existing devices.
方法:该研究是一项受试者内设计,21CI使用者使用纯,复杂,和调制的音调。使用刺激操作来测试CI用户与高通滤波谐波复合物相比是否对低通具有更好的音调辨别能力,并测试在收听调幅音调时提供协变位置提示时,它们是否具有更好的音调辨别能力。
结果:不同条件下的平均值,与复杂或调幅音调相比,参与者对纯音的音调辨别能力更好.与高通谐波复合物相比,参与者对低通的音调辨别能力更好,并且在提供协变位置提示时,对调幅音调的音调辨别能力更好。
结论:CI用户在110至440Hz之间的生态必要音高范围内整合了位置和速率提示。与高通滤波的谐波复合物相比,我们解释了低通观察到的更好的音调区分,对于幅度调制的音调,当提供协变位置提示时,作为为低于440Hz的基频提供激励位置提示的重要性的证据。讨论考虑如何利用现有设备来实现这样的编码。