Developmental hearing loss impairs signal detection in noise: putative central mechanisms.
Developmental hearing loss impairs signal detection in noise: putative central mechanisms.
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DOI：
10.3389/fnsys.2014.00162
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发表时间：
2014
影响因子：
3
通讯作者：
Rosen MJ
中科院分区：
文献类型：
--
作者：
Gay JD;Voytenko SV;Galazyuk AV;Rosen MJ
听力损失的听众在嘈杂的环境中处理声音有困难。这在语音感知中最为明显，但也反映在基本的听觉处理任务中：在噪声背景中检测音调信号，即同时掩蔽。目前尚不清楚同时掩蔽的机制是来自听觉外围还是来自中央听觉系统。感觉神经性听力损失（SNHL）听者的检测不良归因于耳蜗毛细胞损伤。然而，听力损失会改变中枢听觉系统的神经处理。此外，来自正常听力和受损听者的心理物理和神经生理数据表明，同时掩蔽还有其他的贡献，这些贡献集中出现。对于SNHL，很难区分信号检测缺陷的外围和中心贡献。因此，我们通过使用早期传导性听力损失（CHL）的动物模型排除了外周因素，该模型提供听觉剥夺，但不会引起耳蜗损伤。当对成年动物进行测试时，患有CHL的动物在同时噪声中检测音调的阈值增加了。此外，对照动物的细胞内体内记录显示皮层与同时掩蔽相关：局部皮层处理减少了噪音存在时的音调诱发反应。这提出了一种可能性，即早期CHL发生的皮质反应改变甚至可以影响噪声中简单的信号检测。
Listeners with hearing loss have difficulty processing sounds in noisy environments. This is most noticeable for speech perception, but is reflected in a basic auditory processing task: detecting a tonal signal in a noise background, i.e., simultaneous masking. It is unresolved whether the mechanisms underlying simultaneous masking arise from the auditory periphery or from the central auditory system. Poor detection in listeners with sensorineural hearing loss (SNHL) is attributed to cochlear hair cell damage. However, hearing loss alters neural processing in the central auditory system. Additionally, both psychophysical and neurophysiological data from normally hearing and impaired listeners suggest that there are additional contributions to simultaneous masking that arise centrally. With SNHL, it is difficult to separate peripheral from central contributions to signal detection deficits. We have thus excluded peripheral contributions by using an animal model of early conductive hearing loss (CHL) that provides auditory deprivation but does not induce cochlear damage. When tested as adults, animals raised with CHL had increased thresholds for detecting tones in simultaneous noise. Furthermore, intracellular in vivo recordings in control animals revealed a cortical correlate of simultaneous masking: local cortical processing reduced tone-evoked responses in the presence of noise. This raises the possibility that altered cortical responses which occur with early CHL can influence even simple signal detection in noise.