Otoacoustic Emission Cochleography

描述（由申请人提供）：提出的一组实验的目标是对失真积耳声发射（dpoae）进行多维分析。这种方法代表了对“完全参数反应”的检验，它将提供对潜在的耳蜗力学和各种dpoae之间相互关系的更彻底的理解。这些信息有望为临床应用开发更敏感的DPOAE测试。在这个概念框架内，我们打算使用几种策略来研究f2以上dpoae的抑制/增强，以帮助解决这些意想不到的现象是如何产生的重要问题。我们的预期是，耳蜗内产生的谐波相互作用产生差音（f2-fl）发射，负责这些复杂的影响，而不是f3通过催化剂机制产生这些结果的概念。此外，我们计划详细研究下边带（LSB）和上边带（USB） dpoae，尽管这些特殊的发射可以揭示大量关于耳蜗非线性联系的信息，但在该领域很少受到关注。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点。此外，我们认为噪声暴露后的行为将提供耳蜗异常的敏感指标。此外，通过仔细检查固定f2/fl比扫描产生的dpoae，将获得波与固定位置dpoae产生的详细等值面图。这些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的检测oae基本“构建块”的方法。该方法将用于检查非线性DPOAE产生和耳蜗反射在正常和受损耳朵中的变化。最后，根据我们自己的初步发现和其他研究者发表的研究，耳蜗损伤后抑制的增长似乎发生了改变。我们计划开发“抑制”dp图，以揭示抑制的增长作为频率的函数，因此抑制的异常可能与特定受损耳蜗区域的耳蜗功能变化有关。拟议的研究将在正常和噪声暴露的兔子中进行，并且在可行的情况下，在正常听力的人类受试者和噪声性听力损失的患者中进行。

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.