ENCODING OF VOCAL SIGNALS IN THE AUDITORY SYSTEM

描述：这里提出的研究的中心目标是 了解脊椎动物的听觉系统如何识别和解释 庞大的物种曲目--典型的声音交流信号。这个 非哺乳动物声学通信模型的建立提供了一种 了解神经学基本原理的独特而实用的机会 这些操作导致了复杂的听觉系统的进化 包括人类在内的哺乳动物。硬骨鱼是现存的最大的类群 脊椎动物，包括发声物种，具有简单的发声曲目 和一个类似哺乳动物的中枢听觉系统。我们建议 白鳍金枪鱼(Porichthys Notatus)具有发声和发声 行为，以及潜在的神经机制和电路，都是必要的 足以解决挑战所有脊椎动物的声学问题 包括同时(同时)发声的分离。男性 军校鱼在向雌性求爱时同时发声 多次和谐的广告呼唤。三个问题将涉及机制 对于单独的和并发的语音信号的编码和解码： (1)并发语音信号如何分离并在何处由 神经系统？第八神经和听觉的单单位记录 中脑将表征对两个简单信号的反应，如两个音调 节拍和单个多次谐波信号，以及更复杂的刺激，如 两个或多个并发多次谐波信号。中央录音在一起 有了神经解剖学(生物细胞蛋白)，束追踪将绘制出 从属于已识别的听觉编码机制。(2)如何以及在哪里做 听觉和发声通路在前、中、后相互作用 自我发声？中枢性声学通路最近在 学员现在将指导单个单位的研究，以测试假设 提出了声学回路在听觉编码机制中的作用。 (3)语音信号的时间结构是如何影响信息的 是通过听神经纤维传递吗？信息传递措施 传入尖峰序列中存在的信息量(信息 速率)和由棘波序列表示的刺激的质量 (编码效率)。简约(2-3次谐波)和持续时间长(向上 到115分钟)的学员S广告来电呈现独一无二 契机检验S发声信号时间结构假说 被用来优化信息传输，因此 单个并发语音信号的识别。

DESCRIPTION: The central goal of the research proposed here is to understand how the vertebrate auditory system recognizes and interprets an enormous repertoire of species-typical vocal communication signals. The establishment of non-mammalian models of acoustic communication provide a unique and practical opportunity to identify the basic principles of neural operation that have led to the evolution of the complex auditory system of mammals including humans. Teleost fishes are the largest group of extant vertebrates and include vocalizing species with a simple vocal repertoire and a central auditory system resembling that of mammals. We propose that the plainfin midshipman fish (Porichthys notatus) has the vocal and acoustic behaviors, and underlying neural mechanisms and circuitry, both necessary and sufficient to solve acoustic problems that challenge all vertebrates including the separation of simultaneous (concurrent) vocalizations. Male midshipman fish vocalize simultaneously while they court females using multi-harmonic advertisement calls. Three questions will address mechanisms for the encoding and decoding of individual and concurrent vocal signals: (1) How and where are concurrent vocal signals segregated and encoded by the nervous system? Single unit recordings in the eighth nerve and auditory midbrain will characterize responses to both simple signals such as two tone beats and single multi-harmonic signals, and more complex stimuli such as two or more concurrent multi-harmonic signals. Central recordings together with neuroanatomical (biocytin) tract-tracing will map the circuitry that subserves the auditory coding mechanisms identified. (2) How and where do auditory and vocal pathways interact before, during and after self-vocalization? Central vocal-acoustic pathways recently delineated in midshipman will now guide single unit studies that test hypotheses of the proposed role of vocal-acoustic circuitry in auditory coding mechanisms. (3) How does the temporal structure of a vocal signal influence information transmission by auditory nerve fibers? Information transmission measures the amount of information present in an afferent spike train (information rate) and the quality of the stimulus representation by a spike train (coding efficiency). The simplicity (2-3 harmonics) and long duration (up to 115 minutes) of the midshipman s advertisement call presents a unique opportunity to test the hypothesis that a vocal signal s temporal structure is exploited for optimizing information transmission and hence the recognition of individual concurrent vocal signals.