THE EFFERENT AUDITORY SYSTEM AND SIGNAL ANALYSIS

胡子蝙蝠的听觉系统是 对生物反馈和相关神经机制的研究很重要 具有信号检测和分析功能。这些动物的多普勒频移和 幅度补偿，以使回波不受固定目标的影响 特定的频率和强度范围。在这起调查中，行为 而神经生理学研究将在钟摆“飞行”期间进行。 而这些动物正在积极地进行回声定位。双耳蜗牛 麦克风和诱发神经电位将被记录下来，以响应 发射的脉冲和返回的回声以及在安静和 噪音。同时，对补偿的准确性进行评估 在正常情况下和在传出(橄榄耳)中断后 纤维通向毛细胞。这些研究将检验以下假设： 传出纤维在强度和频率辨别中的作用 在检测噪声中的信号方面；这些研究还将用于 评估现有的关于生物声纳系统和 控制听觉输入的机制。结构和人口 传出神经的密度将用各种解剖学方法进行研究。 (透射电子显微镜、扫描电子显微镜、光镜)和组织化学技术。将跟踪光纤路径 通过HRP的使用。该项目是以下长期目标的一部分 理解与外周听觉相关的神经机制 并具有语音、听力和相关的生物反馈机制。

The auditory system of the mustache bat, Pteronotus p. parnellii, is important for the study of biofeedback and neuronal mechanisms associated with signal detection and analysis. These animals Doppler shift and amplitude compensate in order to keep the echoes from fixed targest within specific frequency and intensity ranges. In this investigation behavioral and neurophysiological studies will be carried out during pendulum "flight" while the animals are actively enaged in echolocation. Both cochlear microphonic and evoked neural potentials will be recorded in response to emitted pulses and returning echoes and under conditions of quiet and noise. At the same time the accuracy of the compensation will be assessed under normal conditions and after interruption of efferent (olivocochlear) fibers to the hair cells. These studies will test hypotheses concerning the role of efferent fibers in intensity and frequency discrimination and in the detection of signals in noise; these studies will also be used to assess existing theories on the mechanisms of biosonar systems and mechanisms controlling auditory input. The structure and population density of the efferent nerves will be studied with a variety of anatomical (TEM, SEM, LM) and histochemical techniques. Fiber pathways will be traced with the use of HRP. This project is part of a long term goal of understanding neural mechanisms associated with the peripheral auditory system and with speech, hearing and associated biofeedback mechanisms.