Studies of the central auditory system

这项拟议的研究将研究中枢神经系统在听觉感知和对复杂声音的时间特征的辨别中所起的作用。位于从耳朵到听觉皮质的听觉通路上的神经回路对于识别与环境事件或包括人类语音在内的特定物种的通信信号有关的复杂声音是重要的。外侧丘脑腹侧核(VNLL)是听觉通路中神经元的主要集合，被认为参与处理复杂声音的时间属性。本研究项目将研究VNLL中的神经元如何对声音的时间特征进行分析。我们将记录大鼠VNLL中单个神经元的生理反应，同时将药物应用于细胞，以确定它们的突触化学如何调节听觉反应特征。我们还将检查当VNLL中的活动被药物应用或神经细胞局部损伤阻断时，听觉通路中其他细胞的反应特性。这些研究将使我们能够确定VNLL对中枢听觉处理的功能贡献。此外，我们将进行行为学研究，以确定VNLL的损害如何影响听力，以及动物根据时间结构辨别声音的能力。这些研究将阐明复杂的声音特征是如何由神经回路处理的，并由中枢听觉系统中的神经活动来表示。这些实验的结果也将对理解人类的耳聋和中枢听觉处理障碍具有重要意义。

The proposed research will examine the role of the central nervous system in auditory perception and the discrimination of temporal features of complex sounds. Neural circuits located along the auditory pathway from the ear to auditory cortex are important for the identification of complex sounds associated with environmental events or species-specific communication signals including human speech sounds. The ventral nucleus of the lateral lemniscus (VNLL) is a major collection of neurons in the auditory pathway that is thought to be involved in processing temporal properties of complex sounds. This research project will examine how the neurons in the VNLL contribute to the analysis of temporal features of sounds. We will record physiological responses from single neurons in the rat's VNLL while applying pharmacological agents to the cells to determine how their synaptic chemistry regulates auditory response characteristics. We will also examine the response properties of cells elsewhere in the auditory pathway while activity in the VNLL is blocked by either drug application or local damage of nerve cells. These studies will allow us to determine the functional contribution of the VNLL to central auditory processing. In addition, we will conduct behavioral studies to determine how damage to the VNLL affects hearing and the ability of animals to distinguish sounds based on their temporal structure. The studies will shed light on how complex features of sounds are processed by neural circuits and represented by neural activity within the central auditory system. The outcome of the experiments will also have important implications for understanding deafness and central auditory processing disorders in humans.