Neural mechanisms of auditory temporal pattern perception

项目概要/摘要： 处理声音通信信号是听觉系统最困难但最重要的能力之一。 系统必须实现。这些能力是语言和语音处理的核心，它们的成功或 失败会对整个生命周期的生活质量产生深远的影响。了解神经生物学 支持这些基本能力的机制也为推进辅助听力设备带来了希望 改善对学习障碍和沟通障碍的诊断和治疗， 处理障碍、诵读困难和特定语言障碍。虽然我们已经对基因座有了很多了解 使用非侵入性神经科学技术在人类中进行语言相关处理，这些技术 无法回答单个神经元和神经回路如何实现与语言相关的计算。作为 结果，明确的细胞回路水平和神经计算机制，支持声学 对通信信号处理知之甚少。多方面的研究表明鸣禽可以 为研究与语言相关的共享听觉处理能力提供了一个很好的模型， 特别是通信信号内的时间模式的处理。本文中概述的实验 本研究旨在探讨听觉时间模式加工的神经机制。在人类中， 相邻语音（音素）之间的统计可以帮助或改变音素分类， 提示语言学习者和听众消除感知上相似的声音。对过渡的敏感性 然而，统计并不限于语音信号，而是反映了许多人共享的一般听觉过程。 动物在目标1中，我们研究了复杂听觉对象的分类感知， 皮层神经元的动物模型，并询问这些神经表征是如何影响的时间 上下文除了在序列中出现哪些元素之外，语音处理还需要知道在哪里 这些元素发生。对语音序列的统计特性的敏感性是长期建立的 在婴儿学会说话之前， 成年目标2的研究重点是序列特异性信息如何由单个神经元编码， 听觉皮层的神经群在目标3中，我们提出了一个基本电路，其中人口水平 听觉对象的表征可以通过模式规则进行差异调制，并测试提出的 使用直接、随意操作的模式处理电路。拟议的办法允许在以下方面取得进展： 建立基本语言相关能力的基本神经生物学基础 以及一个总体框架，在这个框架内，可以提出更复杂的、独特的人类过程， 最终测试。

Project Summary/Abstract: Processing acoustic communication signals is among the most difficult, yet vital capabilities that the auditory system must achieve. These abilities lie at the heart of language and speech processing, and their success or failure can have profound impacts on quality of life across the lifespan. Understanding the neurobiological mechanisms that support these basic abilities holds promise for advancing assistive listening devices, as well as improving diagnoses and treatments for learning disabilities and communication disorders such as auditory processing disorder, dyslexia, and specific language impairment. While much has been learned about the loci of language-related processing using non-invasive neuroscience techniques in humans, these techniques cannot answer how individual neurons and neural circuits implement language-relevant computations. As a result, the explicit cellular circuit-level and neuro-computational mechanisms that support acoustic communication signal processing are poorly understood. Multiple lines of research suggest that songbirds can provide an excellent model for investigating shared auditory processing abilities relevant to language, in particular the processing of temporal patterns within communication signals. The experiments outlined in this proposal investigate the neural mechanisms of auditory temporal pattern processing. In humans, the transition statistics between adjacent speech sounds (phonemes) can aid or alter phoneme categorization, providing cues for language learners and listeners to disambiguate perceptually similar sounds. Sensitivity to transition statistics is not exclusive to speech signals however, but reflects general auditory processes shared by many animals. In Aim 1 we investigate the categorical perception of complex auditory objects in populations of cortical neurons in an animal model, and ask how these neural representations are effected by temporal context. In addition to which elements occur in a sequence, speech processing also requires knowing where those elements occur. Sensitivities to the statistical regularities of speech sequences are established long before infants learn to speak, and continue to affect both recognition and comprehension throughout adulthood. Studies in Aim 2 focus on how sequence-specific information is encoded by single neurons and neural populations in auditory cortex. In Aim 3, we propose a basic circuit in which population level representations of auditory objects could be differentially modulated by patterning rules, and test this proposed pattern processing circuit using direct, casual manipulations. The proposed approach permits progress in the near term towards establishing the basic neurobiological substrates of foundational language-relevant abilities and a general framework within which more complex, uniquely human processes, can be proposed and eventually tested.