VM Bloedel Hearing Research Center, CHDD Building, University of Washington, Box 357923, Seattle, Washington 98195, USA.
J Acoust Soc Am. 2012 Dec;132(6):3925-34. doi: 10.1121/1.4763999.
Measures of spectral ripple resolution have become widely used psychophysical tools for assessing spectral resolution in cochlear-implant (CI) listeners. The objective of this study was to compare spectral ripple discrimination and detection in the same group of CI listeners. Ripple detection thresholds were measured over a range of ripple frequencies and were compared to spectral ripple discrimination thresholds previously obtained from the same CI listeners. The data showed that performance on the two measures was correlated, but that individual subjects' thresholds (at a constant spectral modulation depth) for the two tasks were not equivalent. In addition, spectral ripple detection was often found to be possible at higher rates than expected based on the available spectral cues, making it likely that temporal-envelope cues played a role at higher ripple rates. Finally, spectral ripple detection thresholds were compared to previously obtained speech-perception measures. Results confirmed earlier reports of a robust relationship between detection of widely spaced ripples and measures of speech recognition. In contrast, intensity difference limens for broadband noise did not correlate with spectral ripple detection measures, suggesting a dissociation between the ability to detect small changes in intensity across frequency and across time.
用于评估人工耳蜗（CI）使用者频谱分辨率的光谱波纹分辨率测量已成为广泛使用的心理物理工具。本研究的目的是比较同一组 CI 使用者的光谱波纹辨别和检测。在一系列波纹频率下测量波纹检测阈值，并与先前从同一组 CI 使用者获得的光谱波纹辨别阈值进行比较。数据表明，这两种测量方法的性能相关，但两个任务的个体受试者阈值（在恒定的光谱调制深度下）并不相等。此外，在较高的波纹率下，经常发现光谱波纹检测比根据可用光谱线索预期的要高，这使得在较高的波纹率下，时间包络线索可能起作用。最后，将光谱波纹检测阈值与之前获得的语音感知测量值进行比较。结果证实了之前广泛报道的关于广泛间隔波纹检测与语音识别测量之间存在强相关性的报道。相比之下，宽带噪声的强度差异极限与光谱波纹检测测量值不相关，这表明在频率和时间上检测强度小变化的能力与强度差异极限之间存在分离。
