PREDOCTORAL FELLOWSHIP PROGRAM (DISABILITY)

本论文的目的是阐明耳蜗核（CN）和下丘中央核（CNIC）中听觉神经元的功能。了解功能的第一步是找出神经元对什么刺激作出反应，理想情况下不需要先验假设。因此，目的1是开发一种估计具有伪随机噪声刺激的单个听觉神经元的光谱时间加权函数（stwf）的方法。STWF，即神经元在特定时间和频率下赋予声音能量的权重，可以直接用于预测对任意刺激的线性或近线性神经反应。目的2是估计失觉猫CN中神经元的stwf，并使用局部注射阻断抑制输入的药物来确定这些stwf是如何被抑制形成的。目的3是将该方法扩展到包括双耳光谱时间相互作用，当估计失智猫的CNIC中的权重函数时。总之，这些目标的实验将增加对CN和CNIC的电路和功能的理解，并将反过来提示听力障碍和其他听觉障碍如何影响言语和其他复杂声音的处理。

The goal of this thesis proposal is to elucidate the function of auditory neurons in the cochlear nucleus (CN) and central nucleus of the inferior colliculus (CNIC). A first step toward understanding function is to find out what stimuli the neuron responds to, ideally without a priori assumptions. Thus, Aim 1 is to develop a method for estimating the spectrotemporal weighting functions (STWFs) of single auditory neurons with pseudorandom noise stimuli. The STWF, or weights that a neuron assigns to sound energy at certain times and frequencies, can be directly applied to predict linear, or nearly linear, neural responses to arbitrary stimuli. Aim 2 is to estimate the STWFs of neurons in the CN of the decerebrate cat, and use local injection of agents that block inhibitory inputs to determine how these STWFs are shaped by inhibition. Aim 3 is to extend the method to include binaural spectrotemporal interactions when estimating weighting functions in the CNIC of the decerebrate cat. Together, experiments of these aims will increase understanding of circuitry and function in the CN and CNIC, and will in turn suggest how hearing impairment and other auditory disorders affect processing of speech and other complex sounds.