Degrees of relevance? The neuronal representation of sound sources in primary auditory cortex during active localization

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• 批准号: 418090239
• 负责人: Privatdozent Dr. Michael Pecka
• 金额: --
• 依托单位: Lehrstuhl für Neurobiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/418090239?language=en
• 关键词: Degrees; relevance; neuronal; representation; sound

How do we listen to specific talkers within a crowd or localize an individual car in heavy traffic? In everyday life, multiple sound sources are often simultaneously active, yet our brain unravels this mix of sounds into distinct information streams according to the sources of origin. Despite decades of research, a functional understanding of the neuronal mechanisms of this phenomenon, which is termed auditory scene analysis (ASA), remains elusive. Most studies on ASA to date focused on the instant processing of simple sounds in passive (i.e. behaviorally irrelevant) settings and a head-centered (egocentric) reference frame. However, during realistic ASA, there is a continuous modulation of the sensory input. Particularly, since the relative angle between the head and the sound source is constantly changing due to self-motion, a egocentric coding of sound source positions is inadequate. Rather, a representation of absolute (allocentric) sound source location in space would be beneficial. Moreover, ASA is fundamentally characterized by the selective listening to a particular sound source of interest, suggesting that the coding of a sound source likewise depends on its goal-specific relevance.Accordingly, the overall goal of this project is to reveal the neuronal processing and representation of sound source locations during active navigation and its dependency on behavioral relevance. To this end, I developed an ASA paradigm with multiple sound sources, in which freely moving rodents perform selective listening and localization. Using wireless chronic recordings in primary auditory cortex during task performance in this paradigm, I aim to: 1) Determine the nature of spatial representation during active navigation2) Decipher how spatial representations in A1 evolve during the learning of context-specific spatial relevance3) Assess the context-dependency of egocentric representations of behaviourally relevant sound localization cues.

我们如何聆听人群中特定的谈话者或在交通拥堵中定位单独的汽车？在日常生活中，多个声源通常同时处于活动状态，但我们的大脑根据来源将这种声音组合分解为不同的信息流。尽管进行了数十年的研究，但对这种现象的神经机制的功能性理解（称为听觉场景分析（ASA））仍然难以捉摸。迄今为止，大多数关于 ASA 的研究都集中在被动（即行为无关）设置和以头部为中心（以自我为中心）的参考系中对简单声音的即时处理。然而，在实际 ASA 过程中，感觉输入会持续调制。特别地，由于头部和声源之间的相对角度由于自身运动而不断变化，所以声源位置的自我中心编码是不够的。相反，空间中绝对（非中心）声源位置的表示将是有益的。此外，ASA 的根本特征是选择性聆听感兴趣的特定声源，这表明声源的编码同样取决于其特定目标的相关性。因此，该项目的总体目标是揭示神经元处理和主动导航期间声源位置的表示及其对行为相关性的依赖性。为此，我开发了一种具有多个声源的 ASA 范例，其中自由移动的啮齿动物执行选择性监听和定位。在这个范式中，在任务执行期间使用初级听觉皮层的无线慢性记录，我的目标是：1）确定主动导航期间空间表征的性质2）破译A1中的空间表征在学习特定于上下文的空间相关性期间如何演变3）评估行为相关的声音定位线索的自我中心表示的上下文依赖性。