All India Institute of Speech and Hearing, Mysore, India.
PLoS One. 2013;8(2):e55995. doi: 10.1371/journal.pone.0055995. Epub 2013 Feb 7.
The present study evaluated the relation between speech perception in the presence of background noise and temporal processing ability in listeners with Auditory Neuropathy (AN).
The study included two experiments. In the first experiment, temporal resolution of listeners with normal hearing and those with AN was evaluated using measures of temporal modulation transfer function and frequency modulation detection at modulation rates of 2 and 10 Hz. In the second experiment, speech perception in quiet and noise was evaluated at three signal to noise ratios (SNR) (0, 5, and 10 dB).
Results demonstrated that listeners with AN performed significantly poorer than normal hearing listeners in both amplitude modulation and frequency modulation detection, indicating significant impairment in extracting envelope as well as fine structure cues from the signal. Furthermore, there was significant correlation seen between measures of temporal resolution and speech perception in noise.
Results suggested that an impaired ability to efficiently process envelope and fine structure cues of the speech signal may be the cause of the extreme difficulties faced during speech perception in noise by listeners with AN.
本研究评估了伴有听觉神经病变（AN）的听力损失患者在噪声环境下的言语感知与时间处理能力之间的关系。
本研究包括两个实验。在第一个实验中，使用调制传递函数和频率调制检测来评估正常听力者和 AN 患者的时间分辨率，调制率分别为 2Hz 和 10Hz。在第二个实验中，在三个信噪比（SNR）（0、5 和 10dB）下评估安静和噪声环境下的言语感知。
结果表明，AN 患者在幅度调制和频率调制检测方面的表现明显差于正常听力者，这表明他们在从信号中提取包络和精细结构线索方面存在显著障碍。此外，时间分辨率测量值与噪声环境下的言语感知之间存在显著相关性。
结果表明，处理言语信号包络和精细结构线索的能力受损可能是 AN 患者在噪声环境下言语感知面临极端困难的原因。
