Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Halle (Saale), Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany.
Universitätsklinikum Halle (Saale), HNO-Klinik, Ernst-Grube-Str. 40, 06120, Halle (Saale), Germany.
Sci Rep. 2021 Oct 12;11(1):20236. doi: 10.1038/s41598-021-99799-4.
For many cochlear implant (CI) users, frequency discrimination is still challenging. We studied the effect of frequency differences relative to the electrode frequency bands on pure tone discrimination. A single-center, prospective, controlled, psychoacoustic exploratory study was conducted in a tertiary university referral center. Thirty-four patients with Cochlear Ltd. and MED-EL CIs and 19 age-matched normal-hearing control subjects were included. Two sinusoidal tones were presented with varying frequency differences. The reference tone frequency was chosen according to the center frequency of basal or apical electrodes. Discrimination abilities were psychophysically measured in a three-interval, two-alternative, forced-choice procedure (3I-2AFC) for various CI electrodes. Hit rates were measured, particularly with respect to discrimination abilities at the corner frequency of the electrode frequency-bands. The mean rate of correct decision concerning pitch difference was about 60% for CI users and about 90% for the normal-hearing control group. In CI users, the difference limen was two semitones, while normal-hearing participants detected the difference of one semitone. No influence of the corner frequency of the CI electrodes was found. In CI users, pure tone discrimination seems to be independent of tone positions relative to the corner frequency of the electrode frequency-band. Differences of 2 semitones can be distinguished within one electrode.
对于许多人工耳蜗（CI）使用者来说，频率辨别仍然具有挑战性。我们研究了相对于电极频带的频率差异对纯音辨别能力的影响。在一家三级大学转诊中心进行了单中心、前瞻性、对照、心理声学探索性研究。共纳入 34 名 Cochlear Ltd. 和 MED-EL 人工耳蜗使用者和 19 名年龄匹配的正常听力对照组受试者。两个正弦音呈现不同的频率差异。参考音频率根据基底或顶点电极的中心频率选择。使用三间隔、二选一、强制选择程序（3I-2AFC）在各种 CI 电极上进行心理物理测量辨别能力。测量了准确率，特别是针对电极频带拐角频率处的辨别能力。CI 用户的音高差正确判断率约为 60%，正常听力对照组约为 90%。在 CI 用户中，差别阈限为两个半音，而正常听力参与者可以检测到一个半音的差异。未发现 CI 电极拐角频率的影响。在 CI 用户中，纯音辨别能力似乎与相对于电极频带拐角频率的音调位置无关。在一个电极内可以区分 2 个半音的差异。
