Effect of spatial separation and noise type on sentence recognition by Mandarin-speaking cochlear implant users

Abstract

Objectives: To investigate the effects of spatial separation and noise type on sentence recognition by unilateral Mandarin-speaking cochlear implant (CI) users and normal-hearing (NH) listeners.

Method: Twenty-two unilateral Mandarin-speaking CI users and six NH listeners participated in this study. Speech reception thresholds were measured for three noise types (steady state noise, speech babble, and music). Sentences from the Mandarin Speech Perception test were presented directly in front of the listener (0°). Noise was presented from one of the five speaker locations: −90°, −45°, 0°, +45°, and +90°.

Results: Overall, CI performance was significantly poorer than NH performance for all spatial separation and noise type conditions. NH listeners performed best with music and poorest with steady noise. CI users performed best with steady noise, and poorest with babble. Performance was significantly affected by noise location and noise type. There was no significant difference in head shadow effects among the different noise types for CI users.

Conclusions: Performance was much poorer in CI than in NH listeners for all noise types and spatial separations. Noise type differently affected unilateral CI users and NH listeners. The limited spectral resolution in CI users did not appear to affect head shadow.

Chinese abstract

目的：探讨空间分离和噪声类型对说普通话的单侧耳蜗植入（CI）使用者和正常听力（NH）听者的句子识别上的影响。

方法：22名普通话的单侧CI使用者和6名NH听者参与了这项研究。测量三种噪声类型下（稳态噪声, 语音混音和音乐）的语音接收阈值。来自普通话语音感知测试的句子直接呈现在听者面前（0°）。噪声来自5个扬声器位置之一：-90°, -45°, 0°, + 45°和+ 90°。

结果：总体而言, 在所有空间分离和噪声类型条件下, 单侧耳蜗植入（CI）者的表现显著低于正常听力者（NH）的表现。 NH听者在音乐声中表现最好, 在稳定噪音中表现最差。 CI使用者在稳定噪声中表现最好, 在混音中表现最差。表现度受噪音位置和噪音类型的显著影响。 对CI使用者来说, 不同噪声类型之间的头影效应没有显着差异。

结论：在所有噪声类型和空间分离中, CI使用者的表现比NH听着的表现差。噪声类型对单侧CI使用者和NH听者有不同的影响。 CI使用者的有限光谱分辨率似乎没有影响头影。

Keywords:

• Cochlear implant
• speech perception
• head shadow effect
• noise

Acknowledgements

This work was supported by the National Natural Science Foundation of China [81371087, 81570914, 81300818, 81600796], Joint Project of Key Diseases of Health System in Shanghai [2014ZYJB0005], Shanghai Science and Technology Commission Medical Guide Project [134119a1800], and by National Institutes of Health grant [R01-DC004792 and R01-DC004993].

Disclosure statement

The authors report no conflicts of interests.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [81371087, 81570914, 81300818, 81600796], Joint Project of Key Diseases of Health System in Shanghai [2014ZYJB0005], Shanghai Science and Technology Commission Medical Guide Project [134119a1800], and by National Institutes of Health grant [R01-DC004792 and R01-DC004993].