Dorman Michael F, Zeitler Daniel, Cook Sarah J, Loiselle Louise, Yost William A, Wanna George B, Gifford Rene H
Department of Speech and Hearing Science, Arizona State University, Tempe, Ariz., USA.
Audiol Neurootol. 2015;20(3):183-8. doi: 10.1159/000375394. Epub 2015 Apr 18.
In this report, we used filtered noise bands to constrain listeners' access to interaural level differences (ILDs) and interaural time differences (ITDs) in a sound source localization task. The samples of interest were listeners with single-sided deafness (SSD) who had been fit with a cochlear implant in the deafened ear (SSD-CI). The comparison samples included listeners with normal hearing and bimodal hearing, i.e., with a cochlear implant in 1 ear and low-frequency acoustic hearing in the other ear. The results indicated that (i) sound source localization was better in the SSD-CI condition than in the SSD condition, (ii) SSD-CI patients rely on ILD cues for sound source localization, (iii) SSD-CI patients show functional localization abilities within 1-3 months after device activation and (iv) SSD-CI patients show better sound source localization than bimodal CI patients but, on average, poorer localization than normal-hearing listeners. One SSD-CI patient showed a level of localization within normal limits. We provide an account for the relative localization abilities of the groups by reference to the differences in access to ILD cues.
在本报告中，我们使用滤波后的噪声频段，在声源定位任务中限制听众获取双耳声级差（ILD）和双耳时间差（ITD）的能力。感兴趣的样本是单侧耳聋（SSD）患者，他们在患侧耳朵植入了人工耳蜗（SSD-CI）。对照样本包括听力正常和双模式听力的听众，即一只耳朵植入人工耳蜗，另一只耳朵具有低频声学听力。结果表明：（i）SSD-CI条件下的声源定位比SSD条件下更好；（ii）SSD-CI患者依靠ILD线索进行声源定位；（iii）SSD-CI患者在设备激活后1至3个月内表现出功能性定位能力；（iv）SSD-CI患者的声源定位比双模式人工耳蜗患者更好，但平均而言，比听力正常的听众定位能力更差。一名SSD-CI患者的定位水平在正常范围内。我们通过参考获取ILD线索的差异，对各群体的相对定位能力做出了解释。
