ACOUSTIC TRAUMA: HEARING AND SINGLE NEURON ACTIVITY

声损伤：听力和单神经元活动

基本信息

批准号：
3215952
负责人：
RICHARD J SALVI
金额：
$ 16.35万
依托单位：
STATE UNIVERSITY OF NEW YORK AT BUFFALO
依托单位国家：
美国
项目类别：
财政年份：
1987
资助国家：
美国
起止时间：
1987-09-01 至 1991-07-31
项目状态：
已结题

项目摘要

Acoustic trauma causes numerous distortions in hearing such as poor frequency resolution, tinnitus, abnormal temporal processing, loudness recruitment and poor speech discrimination. The range of hearing disorders suggests that the underlying pattern of neural is altered significantly. The goal of this project is document the changes that occur in the discharge patterns of single units in the auditory periphery during noise-induced hearing loss and to relate these changes to the audiological disorders and underlying cochlear pathologies. This project has four separate, but related goals: (1) Recent studies suggest that the breakdown in auditory temporal summation may be partially due to changes in the central auditory pathway. One possibility is that acoustic trauma may alter the properties of certain cells in the cochlear nucleus that are known to exhibit temporal summation. Thus, a goal of the project is to determine if acoustic trauma alters the temporal response characteristics of these cells. (2) Listeners with permanent hearing loss often have prolonged forward masking functions. One underlying neural mechanism for this may be a prolongation in the recovery from short-term neural adaptation. This issue will be examined by measuring the time-course of recovery from short-term adaptation in auditory nerve fibers from animals with noise-induced permanent threshold shift. (3) Hearing-impaired listeners also show a reduced ability to detect the sinusoidal amplitude fluctuations in noise. To investigate the underlying neural basis for this temporal resolution, the response patterns of single auditory nerve fibers to sinusoidally amplitude modulated noise will be compared in normal and hearing-impaired listeners. (4) Finally, the loss of tuning, two-tone suppression and lateral inhibition that occurs in single neurons from noise-exposed ears could significantly alter their input/output functions to broadband signals. Therefore, we plan to use broadband noise and determine how acoustic trauma alters the discharge rate-intensity functions of units in the auditory nerve and cochlear nucleus. Ultimately, we will attempt to relate the neural firing patterns seen in units from noise-exposed animals to the underlying cochlear histopathologies as well as to the psychophysical changes that occur in the noise-exposed animals. These results should help to establish a clearer understanding of the anatomical and physiological basis of the audiological symptoms of noise-induced hearing loss. This may potentially lead to better management and treatment of the hearing-impaired listener.

声学创伤在听力时会引起许多扭曲频率分辨率较差，耳鸣，时间处理异常，响度招募和语音歧视不佳。范围听力障碍表明神经的潜在模式被显着改变。该项目的目标是文档在单位的放电模式中发生的变化噪音引起的听力损失期间的听觉外围这些变化对听力障碍和基础人工耳蜗病理。该项目有四个独立但相关的目标：（1）最近的研究表明听觉的细分时间求和可能部分是由于变化中央听觉路径。一种可能性是声学创伤可能会改变人工耳蜗中某些细胞的特性已知会表现出时间概括。因此，一个目标该项目是确定声学创伤是否改变了时间这些细胞的响应特征。（2）听众永久性听力损失通常会延长前向蒙版功能。一种基本的神经机制可能是从短期神经适应中恢复的延长。该问题将通过测量时间表来检查从听觉神经纤维中的短期改编中恢复来自具有噪声引起的永久阈值移动的动物。（3）听力受损的听众还表现出降低的检测能力噪声中正弦振幅波动。调查该时间分辨率的基本神经基础，响应单听觉神经纤维的模式与正弦振幅将在正常和听力受损中比较调制噪声听众。（4）最后，调谐，两色调抑制和来自噪声暴露的单个神经元中发生的横向抑制耳朵可能会大大改变其输入/输出功能宽带信号。因此，我们计划使用宽带噪声和确定声学创伤如何改变排放速率强度听觉神经和耳蜗核中单元的功能。最终，我们将尝试关联神经射击模式从暴露于噪声的动物到基础的单位可见人工耳蜗组织病理学以及心理物理变化这发生在暴露于噪声的动物中。这些结果应该有所帮助对解剖学和噪声引起的听觉症状的生理基础听力损失。这可能会导致更好的管理和对听力受损的听众的处理。