Coincidence and continuity: uncovering the neural basis of auditory object perception

总结 听觉对象是我们的听觉感知世界的基本组成部分。听觉对象是 形成，部分，由大脑的能力，提取和组织频谱和时间的声音 环境这种能力可以让一个人在拥挤的餐馆噪音中听到他们朋友的声音。 在许多情况下，跨多个频率信道形成时间延迟。这个例子和几个 其他人认为大脑可以在多个频率上跟踪这种时间相关的神经元活动， 引导并使用这种活动作为形成听觉对象和组织听觉环境的手段。 尽管它对听觉感知的重要性很明显，但几乎没有直接证据支持它。 假设时间相关性被编码为时间相关活动，且该活动可以 引导行为。为了填补这一信息空白，我们将联合收割机严格的心理物理学与高密度神经元 记录和计算理论，以确定与动态网络的相互作用的时间 结构和感知。因此，本提案的总体目标是识别 听觉皮层层级学习颞叶-即，环境的巧合和连续性 以及这些神经元的神经表征如何对听觉感知的两个关键组成部分做出贡献： 图形背景分离和知觉不变性，分别。在目标1中，我们将图形背景 分离是由瞬时相关的动态印记到皮层回路中（即， 时间重合）。因此，我们测试是否有音调突发， 同步发作增加了皮层神经元的内在噪声相关性，这反过来又促进了神经元的噪声相关性。 听众在嘈杂的地面刺激中听到人物刺激的能力。在目标2中，我们假设 刺激不变性是从平滑学习的（即，时间上连续的）频谱时间上的变化 听觉刺激的结构。基于这一理论，我们假设大脑在时间上 听觉刺激的连续变化作为潜在听觉对象的自然变换， 驱动不变感知表征的分层学习。无论是个人还是集体， 提供有价值的，定量的见解听觉知觉和其潜在的神经机制。的 PI是唯一有资格进行这项研究的补充专业知识在心理物理学，人口 神经元记录和计算/理论神经科学。

SUMMARY Auditory objects are the foundational building blocks of our auditory-perceptual world. Auditory objects are formed, in part, by the brain’s ability to extract and organize spectral and temporal regularities from the acoustic environment. This ability allows a person to hear their friend’s voice amongst the noise of a crowded restaurant. In many cases, temporal regularities are formed across multiple frequency channels. This example and several others suggest that the brain can track this temporally correlated neuronal activity across multiple frequency channels and uses this activity as a means to form auditory objects and organize the auditory environment. Despite its clear importance to auditory perception, there is little to no direct evidence in support of the hypothesis that temporal regularities are encoded as temporally correlated activity and that this activity can guide behavior. To fill this information gap, we combine rigorous psychophysics with high-density neuronal recordings and computational theory to identify the interaction of temporal regularities with dynamic network structures and perception. Thus, the overall goal of this proposal is to identify the mesoscopic circuits of the auditory cortical hierarchy that learn temporal regularities –i.e., coincidence and continuity– of the environment and how neuronal representations of these regularities contribute to two key components of auditory perception: figure-ground segregation and to perceptual invariance, respectively. In Aim 1, we posit that figure-ground segregation is facilitated by the dynamic imprinting into cortical circuits of instantaneous correlations (i.e. temporal coincidence) across frequency bands of the acoustic target. Thus, we test whether tone bursts with synchronous onsets increase the intrinsic noise correlations of cortical neurons, which, in turn, facilitates a listener’s ability to hear a figure stimulus amongst a noisy ground stimulus. In Aim 2, we hypothesize that stimulus invariances are learned from smooth (i.e., temporally continuous) changes in the spectrotemporal structure of auditory stimuli. Based on this theory, we hypothesize that the brain interprets temporally continuous variations in an auditory stimulus as natural transformations of underlying auditory objects and drives hierarchical learning of invariant perceptual representations. Individually and collectively, the Aims provide valuable, quantitative insights into auditory perception and its underlying neuronal mechanisms. The PIs are uniquely qualified to conduct this research with complementary expertise in psychophysics, population neuronal recordings, and computational/theoretical neuroscience.