HEARING HAZARD ASSOCIATED WITH INDUSTRIAL NOISE EXPOSURE

与工业噪声暴露相关的听力危害

• 批准号: 2277567
• 负责人: Roger P Hamernik
• 金额: $ 20.27万
• 依托单位: PLATTSBURGH STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-08-01 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2277567
• 关键词: biological models; chinchilla; cochlea; environmental stressor; hearing disorders; histology; light microscopy; loudness; model design /development; noise biological effect; noise induced deafness; noise pollution; occupational hazard; vibration perception

Hearing loss in industrial workers accumulates from repeated daily (interrupted) exposures to excessive noise over a long period of employment. Most strategies designed to estimate hearing loss rely either upon extrapolations from experimental data acquired from short-term acute exposures or from noninterrupted long-term noise exposures or from epidemiological data with its typically 70 dB or more across-subject variability. Recent discoveries show that the peripheral auditory system can modulate the effects of noise exposure as much as 40 dB. These effects are believed to be partially mediated by the outer hair cell motor system which can be activated by a low-level noise exposure that precedes a hazardous noise exposure, or by interrupting a daily noise exposure regime. The outer hair cell bi-directional transduction system is also responsible for generating cochlear emissions which are now being intensively studied because of their potential use as a noninvasive and objective diagnostic test for noise-induced changes in outer hair cell function. Exposure to high-level impact noise continues to pose a problem to hearing in many industrial environments. Furthermore, there is virtually no experimental data on the accumulation of hearing loss from interrupted high-level impact noise and relatively little data available on the relation between cochlear emissions and noise-induced sensory cell pathology. Similarly, our knowledge of how low-level noise outside the work place affects hearing loss acquired in the work environment is very inadequate. The proposed research is designed to study the issues raised above in an animal model (chinchilla)by using as stimuli: (a) narrow band (400 Hz) impacts with center frequencies between 0.5 and 8.0 kHz to probe a wide frequency extent of the cochlea; (b) broad band impacts; and (c) complex high kurtosis continuous noise. The exposure paradigms will include both interrupted and noninterrupted exposures for 20 days and 5 days respectively. Exposures will be balanced for total energy so that comparisons based on energy can be made with existing data. Pure tone hearing threshold measured using evoked response audiometry and cubic distortion product evoked cochlear emission audiograms and input/output functions will be collected and correlated with sensory cell pathology. The objective is to contribute to: (l) an understanding of how hearing loss accumulates from repeated interrupted impact and complex noise exposures; (2) the development of the distortion product emission as an objective noninvasive diagnostic tool; and (3) an understanding and prediction of individual susceptibility to noise-induced hearing loss.

工业工人的听力损失从每天重复的 （间断）长时间暴露于过量噪音， 就业 大多数用于评估听力损失的策略依赖于 根据从短期急性 暴露或不间断的长期噪声暴露或 流行病学数据，其典型的70 dB或更高的跨学科 可变性 最近的发现表明，外周听觉系统 可以调节高达40分贝的噪音暴露的影响。 这些 据信，这种作用部分由外毛细胞马达介导， 一种可以被低水平噪声暴露激活的系统， 有害噪音暴露，或中断日常噪音暴露 政权 外毛细胞双向转导系统还 负责产生耳蜗发射， 由于其作为一种非侵入性的， 噪声引起外毛细胞变化的客观诊断试验 功能 暴露在高水平的冲击噪音中仍然是一个问题 在许多工业环境中的听觉。此外，还有 几乎没有关于听力损失累积的实验数据， 间断的高水平撞击噪音和相对较少的可用数据 耳蜗辐射与噪声诱发感觉细胞的关系 病理同样，我们对外界低水平噪音的了解 工作场所对后天性听力损失的影响在工作环境中是非常 不足 拟议的研究旨在研究所提出的问题 在动物模型（栗鼠）中，通过使用以下作为刺激：（a）窄带 (400 Hz）的冲击，中心频率在0.5和8.0 kHz之间 耳蜗的宽频率范围;（B）宽带影响;以及（c） 复杂的高峰度连续噪声。 暴露模式将 包括20天和5天间断和非间断暴露 天分别。暴露将与总能量平衡， 可以与现有数据进行基于能量的比较。 纯音 使用诱发反应测听法和立方 畸变产物诱发耳蜗发射听力图和输入/输出 将收集功能并与感觉细胞病理学相关联。 目的是促进：（l）了解听力如何 由于反复间断的冲击和复杂的噪音， （2）畸变产物发射的发展， 客观的非侵入性诊断工具;（3）理解和 预测个体对噪声性听力损失的易感性。