Cochlear toughening, protection, and potentiation of noise-induced trauma by non-Gaussian noise
Cochlear toughening, protection, and potentiation of noise-induced trauma by non-Gaussian noise
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DOI：
10.1121/1.1531981
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发表时间：
2003-02-01
影响因子：
2.4
通讯作者：
Davis, B
中科院分区：
文献类型：
--
作者：
Hamernik, RP;Qiu, W;Davis, B
足够强度的间断噪声暴露，以每天重复的周期呈现，在暴露的第一天之后产生阈值偏移（TS）。在暴露序列的随后几天测量的TS已被证明相对于。初始TS。尽管持续的每日暴露方案，TS的这种降低被称为耳蜗增韧效应，并且暴露被称为增韧暴露。四组龙猫暴露于四种不同的噪音中断（6小时/天，20天）。或不间断（24小时/天，持续5天）计划。暴露具有相等的总能量，100 dB（A）SPL的总体水平，以及大致相同的平坦宽带长期频谱。这些噪声的主要区别在于它们的时间结构;两个是高斯的，两个是非高斯的，非平稳的。脑干听觉诱发电位用于估计听阈和表面制备组织学。实验结果表明：（1）暴露于中断的高电平非高斯信号，产生与等效中断高斯噪声产生的效果相当的增韧效果。(2)无论是由高斯噪声还是非高斯噪声产生的韧化，与等效的不间断噪声相比，都会导致减少的创伤，以及（3）连续和间断的非高斯暴露都会比能量和光谱等效的高斯噪声产生更多的创伤。在20天的暴露过程中，每天暴露后的TS模式可能呈现出各种配置：这些结果不支持等能量假设作为估计噪声暴露产生听力损失的可能性的统一原则：，2003年美国声学学会。
An interrupted noise exposure of sufficient, intensity, presented on a daily repeating cycle, produces a threshold shift (TS) following the first day of exposure. TSs measured on subsequent days of the exposure sequence have been shown to decrease relative to the. initial TS. This reduction of TS, despite the continuing daily exposure regime, has been called a cochlear toughening effect and the exposures referred to as toughening exposures. Four groups of chinchillas were exposed to one of four different noises presented on an interrupted (6 h/day for 20 days). or noninterrupted (24 h/day for 5 days) schedule. The exposures had equivalent total energy, an overall level of 100 dB(A) SPL, and approximately the same flat, broadband long-term spectrum. The noises differed primarily in their temporal structures; two were Gaussian and two were non-Gausssian, nonstationary. Brainstem auditory evoked potentials were used to estimate hearing thresholds and surface preparation histology. was used to determine sensory cell loss: The experimental results presented here show that: (1) Exposures to interrupted high-level, non-Gaussian signals,produce a toughening effect comparable to that produced by an equivalent interrupted Gaussian noise. (2) Toughening, whether produced by Gaussian or non-Gaussian noise, results in reduced trauma compared to the equivalent uninterrupted noise, and (3) that both continuous and interrupted non-Gaussian exposures produce more trauma than do energy and spectrally equivalent Gaussian noises. Over the course of the 20-day exposure; the pattern of TS following each day's exposure could exhibit a variety of configurations: These results do not support the equal energy hypothesis as a unifying principal for estimating the potential of a noise exposure to produce hearing loss:, 2003 Acoustical Society of America.