A series of Gaussian and non-Gaussian equal energy noise exposures were designed with the objective of establishing the extent to which the kurtosis statistic could be used to grade the severity of noise trauma produced by the exposures. Here, 225 chinchillas distributed in 29 groups, with 6 to 8 animals per group, were exposed at 97 dB SPL. The equal energy exposures were presented either continuously for 5 d or on an interrupted schedule for 19 d. The non-Gaussian noises all differed in the level of the kurtosis statistic or in the temporal structure of the noise, where the latter was defined by different peak, interval, and duration histograms of the impact noise transients embedded in the noise signal. Noise-induced trauma was estimated from auditory evoked potential hearing thresholds and surface preparation histology that quantified sensory cell loss. Results indicated that the equal energy hypothesis is a valid unifying principle for estimating the consequences of an exposure if and only if the equivalent energy exposures had the same kurtosis. Furthermore, for the same level of kurtosis the detailed temporal structure of an exposure does not have a strong effect on trauma.
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机译:设计了一系列高斯和非高斯等能量噪声暴露,其目的是确定峰度统计可用于对暴露所产生的噪声创伤的严重程度进行分级的程度。在这里,分布在29组中的225只龙猫,每组6至8只动物,暴露于97 dB SPL。连续暴露5 d或中断19 d的能量暴露相等。非高斯噪声在峰度统计量的水平或噪声的时间结构上都不同,后者由嵌入在噪声信号中的冲击噪声瞬变的不同峰值,间隔和持续时间直方图定义。根据听觉诱发的潜在听觉阈值和量化感觉细胞损失的表面准备组织学估计噪声诱发的创伤。结果表明,当且仅当当量能量暴露具有相同峰度时,等能量假设才是估计暴露后果的有效统一原则。此外,对于相同水平的峰度,暴露的详细时间结构不会对创伤产生强烈影响。
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