Otoacoustic Emission Cochleography

描述(由申请人提供)：拟议的一组实验的一个目标是对失真产物耳声发射(DPOAE)进行多维分析。这种方法代表了对“完全参数反应”的研究，这将提供对基本的耳蜗力学和不同DPOAE之间的相互关系的更全面的理解。这些信息有望为临床应用开发更灵敏的DPOAE测试做出贡献。在这个概念框架内，我们打算使用几种策略来研究抑制/增强f2以上的DPOAE，以帮助解决这些意外现象是如何产生的这一重要问题。我们的预期是，耳蜗内产生的谐波相互作用，产生导致这些复杂影响的不同音调(f2-f1)发射，而不是认为f3通过催化机制产生这些结果。此外，我们计划详细研究下边带(LSB)和上边带(USB)DPOAE，这两种DPOAE在该领域几乎没有受到关注，尽管这些特定的发射可以揭示大量关于耳蜗非线性联系的信息。我们建议使用STC技术来确定LBS和USB DPOAE是否具有独特的生成位置。此外，我们认为，他们在噪音暴露后的行为将提供一个敏感的指标耳蜗术后的异常。此外，通过仔细检查固定f2/f1比扫描产生的DPOAE，将获得波与位置固定的DPOAE产生的详细等高面图。这些曲线图的相位特征提供了一种基于非线性失真和线性相干反射过程来检查OAEs的基本“积木”的方法。这一方法将被用来检查正常耳朵和受损耳朵的非线性DPOAE产生和耳蜗反射的变化。最后，根据我们自己的初步发现和其他研究人员发表的研究，抑制的增长似乎在耳蜗性侮辱后发生了变化。我们计划开发“抑制”DP图，以揭示抑制作为频率函数的增长，以便抑制中的异常可以与特定受损耳蜗区的耳蜗功能变化相关。拟议的研究将在正常和噪声暴露的兔子身上进行，如果可行，将在听力正常的人类受试者和噪声性听力损失患者中进行。

DESCRIPTION (provided by applicant): A goal of the proposed set of experiments is to perform a multidimensional analysis of distortion-product otoacoustic emissions (DPOAEs). This approach represents an examination of the "complete parametric response", which will provide a more thorough understanding of the underlying cochlear mechanics and the interrelationships among the various DPOAEs. Such information promises to contribute toward developing more sensitive DPOAE tests for clinical applications. Within this conceptual framework, we intend to examine suppression/enhancement of DPOAEs above f2 using several tactics to help resolve the important issue of how these unanticipated phenomena are produced. Our expectation is that harmonics generated within the cochlea interact to produce difference-tone (f2-fl) emissions that are responsible for these complex effects as opposed to the notion that f3 produces these outcomes via a catalyst mechanism. Moreover, we plan to investigate in detail both lower- (LSB) and upper sideband (USB) DPOAEs, which have received little focused attention in the field, although a great deal of information about cochlear nonlinear ties can be revealed by these particular emissions. We propose to use STC techniques to determine if LBS vs USB DPOAEs have unique sites of generation. Additionally, we believe that their behavior following noise exposure will provide a sensitive index of cochlear abnormality. Further, by carefully examining DPOAEs generated with fixed f2/fl-ratio sweeps, detailed contour-surface plots of the generation of wave vs. place fixed DPOAEs will be obtained. The phase characteristics of these plots provide a means of examining the fundamental 'building blocks' of OAEs based upon nonlinear distortion and linear-coherent reflection processes. This approach will be used to examine changes in nonlinear DPOAE generation and cochlear reflection in normal vs. impaired ears. Finally, according to our own preliminary findings and the published studies of other investigators, growth of suppression appears to be altered following cochlear insult. We plan to develop 'suppression' DP-grams to reveal growth of suppression as a function of frequency so that abnormalities in suppression can be related to changes in cochlear function across a specific damaged cochlear region. The proposed studies will be conducted in both normal and noise-exposed rabbits and, whenever feasible, in both normal-hearing human subjects and patients with noise-induced hearing loss.