Hearing Deficit Due to Auditory Neuropathy

听觉神经病变导致的听力缺陷

• 批准号: 6985174
• 负责人: Arnold Starr
• 金额: $ 48.89万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6985174
• 关键词: acoustic nerve; auditory cortex; auditory pathways; behavior test; clinical research; cochlear implants; cues; electrophysiology; human subject; neural information processing; neuropathology; psychoacoustics; sensory neuropathy; sound perception; speech recognition

DESCRIPTION (provided by applicant): This proposal will study a recently recognized form of hearing disorder called auditory neuropathy (AN) that is due to a disorder of auditory nerve functions in the presence of normal cochlear receptor activities. AN subjects have normal measures of cochlear outer hair cell activities but abnormal measures of the central auditory pathway functions beginning with auditory nerve. The hearing disorder typically affects speech comprehension out-of-proportion to the pure tone loss, particularly speech recognition in noise. AN is not rare and accounts for 10 percent of newborns identified as having hearing loss and also develops in childhood and in adults. In adults the disorder of auditory nerve is commonly associated with a peripheral neuropathy. In addition, AN and sensory hearing loss occur together. Loss of neural synchrony and decreased auditory nerve input are proposed as cardinal mechanisms underlying the hearing disorder. The sites of abnormality along auditory nerve have recently been identified at auditory ganglion cells and their axons (Type I AN) or distally in the auditory periphery where auditory nerve terminals, inner hair cells, and the synapses between inner hair cells with nerve terminals are in close approximation (Type II AN). Our long-term goals are to understand the underlying mechanisms of AN and the accompanying hearing impairments to provide a scientific basis for alleviating the hearing deficit in AN subjects. We propose four experiments using both psychophysical and electrophysiological techniques that will help us achieve these goals. We will characterize (1) the reorganization of central auditory pathway occurring in response to altered auditory nerve input; (2) the contributions of dysynchronization and decreased auditory input as pathophysiological mechanisms underlying AN; (3) the objective physiological and psychophysical measures of improved auditory temporal processes in cochlear implanted AN subjects, and (4) the improvement of speech recognition using new auditory processing techniques. The results of our studies could have major impact on the diagnosis, classification, understanding, and treatment of auditory neuropathy.

描述(由申请人提供)：这项提案将研究一种最近被确认的听力障碍形式，称为听神经病(AN)，它是由于在存在正常的耳蜗感受器活动的情况下听神经功能障碍引起的。受试者有正常的耳蜗外毛细胞活动测量，但从听神经开始的中枢听觉通路功能测量异常。听力障碍对语音理解的影响通常与纯音损失不成比例，尤其是在噪声中的语音识别。耳聋并不罕见，占被确认为听力损失的新生儿的10%，也会在儿童和成人中发展。在成年人中，听神经紊乱通常与周围神经病变有关。此外，耳聋和感觉性听力损失是同时发生的.神经同步性丧失和听神经输入减少被认为是听力障碍的主要机制。最近发现听神经异常的部位在听神经节细胞及其轴突(Ian型)或远端的听神经末梢、内毛细胞以及内毛细胞与神经末梢之间的突触(IIan型)。我们的长期目标是了解听神经炎及其伴随的听力损伤的潜在机制，为缓解听神经炎受试者的听力障碍提供科学依据。我们提出了四个同时使用心理物理和电生理技术的实验，以帮助我们实现这些目标。我们将描述(1)听神经输入改变而发生的中枢听觉通路的重组；(2)作为AN基础的病理生理机制的同步性失调和听觉输入减少的贡献；(3)人工耳蜗植入AN受试者中改善听觉临时过程的客观生理和心理物理措施；以及(4)新的听觉处理技术对语音识别的改善。我们的研究结果可能会对听神经病的诊断、分类、理解和治疗产生重大影响。