Effects of stimulation rate, mode and level on modulation detection by cochlear implant users
Effects of stimulation rate, mode and level on modulation detection by cochlear implant users
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DOI：
10.1007/s10162-005-0007-6
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发表时间：
2005-09-01
影响因子：
2.4
通讯作者：
Fu, QJ
中科院分区：
文献类型：
--
作者：
Galvin, JJ;Fu, QJ
在人工耳蜗植入（CI）患者中，时间处理通常在低听力水平下最差，使得对噪声中的辅音识别和/或语音感知重要的低振幅时间线索的感知困难。目前还不清楚语音处理器参数，如刺激速率和刺激模式可能会影响时间处理，特别是在低听力水平。本研究调查了这些参数对调制检测的影响，由六个CI用户。调制检测阈值（MDT）作为刺激速率，模式和水平的函数进行测量。结果表明，对于所有的刺激率和模式条件下，调制灵敏度是最差的安静听的水平，从以前的研究结果一致。MDT在较低的刺激率下更好，特别是对于安静到中等的听力水平。刺激模式对MDT无显著影响。这些结果表明，虽然高刺激率可以更好地编码时间信息和扩大电极动态范围，CI患者可能无法访问这些增强的时间线索，特别是在较低的部分的动态范围。较低的刺激速率可以提供对弱声学包络信息的更好识别。
In cochlear implant (CI) patients, temporal processing is often poorest at low listening levels, making perception difficult for low-amplitude temporal cues that are important for consonant recognition and/or speech perception in noise. It remains unclear how speech processor parameters such as stimulation rate and stimulation mode may affect temporal processing, especially at low listening levels. The present study investigated the effects of these parameters on modulation detection by six CI users. Modulation detection thresholds (MDTs) were measured as functions of stimulation rate, mode, and level. Results show that for all stimulation rate and mode conditions, modulation sensitivity was poorest at quiet listening levels, consistent with results from previous studies. MDTs were better with the lower stimulation rate, especially for quiet-to-medium listening levels. Stimulation mode had no significant effect on MDTs. These results suggest that, although high stimulation rates may better encode temporal information and widen the electrode dynamic range, CI patients may not be able to access these enhanced temporal cues, especially at the lower portions of the dynamic range. Lower stimulation rates may provide better recognition of weak acoustic envelope information.