CELLULAR BASIS FOR SIGNAL PROCESSING IN AUDITORY SYSTEM

目的是了解中枢处理的细胞基础， 细胞类型的特定双耳和单耳电路，从 耳蜗核到下丘。直接地或经由 上级橄榄核和外侧丘系。 一个跨学科 方法将表征结构，电生理， 这些回路的神经化学性质，特别是抑制性的 件. 将研究细胞类型的突触连接 在解剖学上，虽然它们对声刺激的响应特性 将被生理学定义，并标记相关的神经元组， 通过记录电极进行微标记。 细胞化学 标记将定位传入输入中的可疑递质 这些细胞类型。 这些输入对生成的贡献 将通过刺激或阻断它们来研究神经元的反应 神经化学在结合解剖学和生理学实验。 这些分析将有助于形成有用的突触机制模型 电路中每种类型神经元的响应特性的基础。 这是必要的，以解释细胞的机制， 这些回路在正常知觉中的运作及其变化 对创伤的反应 成熟耳蜗核对 声损伤，如噪音引起的感音神经性听力损失 耳蜗损伤，将根据新生长的 轴突和递质的神经化学，这可能涉及 抑制性突触 最后，在双耳神经元的反应， 下丘将进行生理学分析与声学 已知的能引起优先效应的刺激。 的假设 双耳感知效应背后的神经活动 依赖于听觉的抑制机制。

The goal is to understand the cellular basis for central processing in specific binaural and monaural circuits of cell types, extending from the cochlear nucleus to the inferior colliculus. either directly or via the nuclei of the superior olive and lateral lemniscus. An interdisciplinary approach will characterize the structural, electrophysiological, and neurochemical properties of these circuits, especially the inhibitory components. The synaptic connections of the cell types will be studied anatomically, while their response properties to acoustic stimulation will be defined physiologically and the related groups of neurons labeled with micromarkers through the recording electrodes. Cytochemical labeling will localize the suspected transmitters in the afferent inputs to these cell types. The contributions of these inputs to the generation of the neuronal responses will be studied by stimulating or blocking them neurochemically in combined anatomical and physiological experiments. The analysis will help to form useful models of the synaptic mechanisms underlying the response properties of each type of neuron in the circuit. This is necessary to explain the cellular mechanisms governing the operation of these circuits in normal perception and their alterations in response to trauma. The reaction of the mature cochlear nucleus to acoustic trauma, as evinced in sensorineural hearing loss due to noise damage of the cochlea, will be assessed in terms of the new growth of axons and the neurochemistry of the transmitters, which may involve inhibitory synapses. Finally the binaural responses of neurons in the inferior colliculus will be analyzed physiologically with acoustic stimuli that are known to elicit the precedence effect. The hypothesis is that the neural events underlying the binaural perceptual effect depend on inhibitory mechanisms in hearing.