Dynamic processing of sound in auditory cortex

项目摘要： 言语和语言的感知需要听觉皮层的正常功能 （ACX）。ACX如何做到这一点，关键取决于人口的协调活动， 神经元：既跨越皮层，又贯穿其多层结构。初级听觉 皮层（A1）对声音感知起着关键作用，因为它代表了第一个皮层 加工站。最近的研究结果表明，A1神经元的神经活动不依赖于 只依赖于听觉刺激本身，但受到声音历史，内部状态， 和动物行为的背景。例如，单个A1神经元的选择性可以 当动物从事行为任务时，或者当动物 听力条件变得更具挑战性。然而，行为相关信息是 编码在神经元群体中，但到目前为止，还不清楚行为如何影响 塑造A1神经群体的活动，以及由此产生的群体活动如何相互关联 to task任务performance性能.在这里，我们确定声音是如何动态编码在不同的细胞 行为过程中的群体及其细胞内相互作用的变化性质， A1层。 通过在行为小鼠中使用体内双光子成像，我们将确定功能性 在确定的大量A1神经元对复杂刺激的反应中，这些神经元如何 相互作用，重建与A1存在的功能网络，并分享外部影响， A1网络然后，我们研究A1网络如何改变他们的反应， 在不同任务难度的听觉行为过程中的功能相互作用。因此，我们确定 网络的变化取决于任务的识别和难度。所有这些 实验将揭示A1网络是如何动态重新配置的，这取决于 动物的行为需求。我们之前的工作确定了额叶皮层的一个区域， 眶额皮层（OFC），作为A1的输入源，可以改变A1感受野。我们 从而研究OFC投射在听觉行为中的参与情况， 操纵OFC投射到A1将改变行为表现。 我们的工作有助于从机理上理解正常听力的能力 听众导航复杂或嘈杂的声学环境，并将注意力转移到 不同的声源。因此，我们的工作有助于了解不同的条件， 如耳鸣、衰老、诵读困难、中央听觉处理障碍（CAPD）。

Project Summary: The perception of speech and language requires normal functioning of the auditory cortex (ACX). How ACX does this critically depends on the coordinated activity of populations of neurons: both across the cortex and throughout its multi-layered structure. The primary auditory cortex (A1) plays a key role for sound perception since it represents one of the first cortical processing stations. Recent results have shown that neural activity of A1 neurons depend not only on auditory stimuli themselves, but are influenced by the history of sounds, internal state, and behavioral context of the animal. For example, the selectivity of individual A1 neurons can rapidly and adaptively be reshaped when an animal is engaged in a behavioral task, or when listening conditions become more challenging. However, behaviorally relevant information is encoded in populations of neurons but to date it is not understood how behavioral influences shape the activity across A1 neural populations, and how the resulting population activity relates to task performance. Here we determine how sounds are dynamically encoded in diverse cell populations during behavior and the changing nature of their cellular interactions within and across A1 layers. By using in vivo 2-photon imaging in behaving mice we will determine the functional responses to complex stimuli in identified large populations of A1 neurons, how these neurons interact, reconstruct the functional networks present with A1, and shared external influences on these A1 networks. We then investigate how A1 networks change their responses and functional interactions during auditory behaviors of varying task difficulty. Thus, we determine how network changes depend on the identify and the difficulty of a task. Together, these experiments will reveal how A1 networks are dynamically reconfigured depending on the behavioral needs of the animal. Our prior work identified a region of the frontal cortex, the orbitofrontal cortex (OFC), as a source of inputs to A1 that can change A1 receptive fields. We thus investigate how OFC projections are engaged during auditory behaviors and if manipulating OFC projections to A1 will alter behavioral performance. Our work contributes to the mechanistic understanding of the ability of normal-hearing listeners to navigate complex or noisy acoustic environments and shift their attention between different sound sources. Thus, our work contributes to the understanding of diverse conditions such as tinnitus, aging, dyslexia, central auditory processing disorder (CAPD).