Serrao Delora Samantha, Theruvan Nikhitha, Fathima Hasna, Pitchaimuthu Arivudai Nambi
National Hearing Care, Armadale, Australia.
Department of Audiology, La Trobe University, Melbourne, Australia.
Int Arch Otorhinolaryngol. 2024 Jul 5;28(3):e492-e501. doi: 10.1055/s-0044-1785456. eCollection 2024 Jul.
The limited access to temporal fine structure (TFS) cues is a reason for reduced speech-in-noise recognition in cochlear implant (CI) users. The CI signal processing schemes like electroacoustic stimulation (EAS) and fine structure processing (FSP) encode TFS in the low frequency whereas theoretical strategies such as frequency amplitude modulation encoder (FAME) encode TFS in all the bands. The present study compared the effect of simulated CI signal processing schemes that either encode no TFS, TFS information in all bands, or TFS only in low-frequency bands on concurrent vowel identification (CVI) and Zebra speech perception (ZSP). Temporal fine structure information was systematically manipulated using a 30-band sine-wave (SV) vocoder. The TFS was either absent (SV) or presented in all the bands as frequency modulations simulating the FAME algorithm or only in bands below 525 Hz to simulate EAS. Concurrent vowel identification and ZSP were measured under each condition in 15 adults with normal hearing. The CVI scores did not differ between the 3 schemes (F = 0.62, = 0.55, η = 0.04). The effect of encoding TFS was observed for ZSP (F = 5.73, = 0.008, η = 0.29). Perception of Zebra speech was significantly better with EAS and FAME than with SV. There was no significant difference in ZSP scores obtained with EAS and FAME ( = 1.00) For ZSP, the TFS cues from FAME and EAS resulted in equivalent improvements in performance compared to the SV scheme. The presence or absence of TFS did not affect the CVI scores.
人工耳蜗（CI）使用者在噪声环境中语音识别能力下降的一个原因是获取时间精细结构（TFS）线索的机会有限。像电声刺激（EAS）和精细结构处理（FSP）这样的CI信号处理方案在低频中编码TFS，而诸如频率幅度调制编码器（FAME）等理论策略则在所有频段中编码TFS。 本研究比较了模拟CI信号处理方案的效果，这些方案要么不编码TFS、在所有频段编码TFS信息，要么仅在低频段编码TFS对并发元音识别（CVI）和斑马语音感知（ZSP）的影响。 使用30频段正弦波（SV）声码器系统地操纵时间精细结构信息。TFS要么不存在（SV），要么作为模拟FAME算法的频率调制出现在所有频段中，要么仅出现在525Hz以下的频段中以模拟EAS。在每种条件下，对15名听力正常的成年人进行并发元音识别和ZSP测量。 三种方案之间的CVI得分没有差异（F = 0.62，p = 0.55，η² = 0.04）。观察到编码TFS对ZSP有影响（F = 5.73，p = 0.008，η² = 0.29）。与SV相比，EAS和FAME对斑马语音的感知明显更好。EAS和FAME获得的ZSP得分没有显著差异（p = 1.00） 对于ZSP，与SV方案相比，来自FAME和EAS的TFS线索在性能上带来了同等程度的改善。TFS的存在与否不影响CVI得分。
