DEVELOPMENT/INFLUENCE--INHIBITION IN AUDITORY SYSTEM

总体目标是全面描述 中枢神经抑制的功能和结构发展 长爪沙鼠（Meriones unguiculatus）的听觉核。 研究 计划可分为三个具体方面：（1）功能 发展 抑制性和兴奋性的发育表现 将在外侧上级橄榄中定量突触后电位 (LSO)神经元，使用沙鼠脑切片制备。 延迟， 振幅和突触后电位的数量将用 标准的细胞内技术， 年龄 (2)解剖学发展。 轴突乔木的成熟从一个 投射抑制核，斜方体内侧核 （MNTB），LSO将通过细胞内染料填充获得， 流程. 每一个的绝对大小和解剖分布 将对Arbor进行评估。 特别值得注意的是， 实验，将是任何缺乏特异性的迹象， 功能性抑制接触，旺盛的轴突乔木）。 （三） 神经抑制的个体发育影响。 发育 功能上消除对大脑的抑制性投射的后果 LSO将以两种方式进行评估。 抑制活性对 通过测量LSO细胞大小来分析突触后结构。 的 对听觉功能的影响将通过测量刺激来分析 LSO神经元的特异性和兴奋性神经元的相对功效 和抑制性传入通路。 这些实验将有助于 我们对这些听觉编码特性成熟的理解 依赖于抑制，而中枢神经系统的退行性变化 听觉系统伴随传导性和感音神经性听力损失。

The overall goal is to provide a comprehensive description of the functional and structural development of neural inhibition in a central auditory nucleus of the gerbil (Meriones unguiculatus). The research plan can be divided into three specific areas: (1) Functional development. The developmental appearance of inhibitory and excitatory postsynaptic potentials will be quantified in lateral superior olivary (LSO) neurons, using the gerbil brain slice preparation. The latency, amplitude, and number of postsynaptic potential will be measured with standard intracellular techniques from animals of increasing postnatal age. (2) Anatomical development. The maturation of axonal arbors from a projection inhibitory nucleus, the medical nucleus of the trapezoid body (MNTB), to the LSO will be obtained by intracellular dye-filling of the processes. The absolute size, and the anatomical distribution of each arbor will be evaluated. Of particular interest in the two descriptive experiments, will be any indications of a lack of specificity during functional inhibitory contacts, exuberant axonal arbors). (3) Ontogenetic influence of neural inhibition. The developmental consequences of functionally eliminating the inhibitory projection to the LSO will be assessed in two ways. The effects of inhibitory activity on postsynaptic structure will be assayed by measuring LSO cell size. The effects on auditory function will be assayed by measuring the stimulus specificity of LSO neurons and the relative efficacy of the excitatory and inhibitory afferent pathways. These experiments will contribute to our understanding of the maturation of those auditory coding properties which rely on inhibition, and the degenerative changes in the central auditory system attendant to conductive and sensorineural hearing loss.