Representation of auditory space in the avian midbrain: integration without a map?

鸟类中脑听觉空间的表示：没有地图的整合？

• 批准号: 407815744
• 负责人: Professor Dr. Harald Luksch
• 金额: --
• 依托单位: Lehrstuhl für Zoologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/407815744?language=en
• 关键词: Representation; auditory; space; avian; midbrain

While spatial vision in birds is well understood, spatial auditory processing remains puzzling for most avian species. Even though most bird species move in all three dimensions in a highly structured world, auditory localization is believed to be restricted to the azimuth in most birds, that is, only along the horizontal dimension. Elevational cues to determine the height of a sound source are usually introduced by outer ear structures that most bird species do not possess; only specialists such as the barn owl have anatomical features (such as asymmetric ear openings) that allow localization in elevation. However, recent data have shown that the spherical avian head induces acoustic nonlinearities that might allow sound localization in elevation by head movements. We will study this behavior in chicken in a controlled paradigm to determine whether non-specialists species are indeed able to locate sound in all dimensions. In addition, we will investigate how the auditory information is integrated into the map of visual space in the midbrain optic tectum. If the auditory system is indeed incapable of locating sounds in elevation, how can auditory information be integrated into the precise map of visual space in the tectum? We will record the responses of midbrain neurons under auditory, visual, and audio-visual stimulation to determine the receptive fields in each modality and delineate the integration rules. Preliminary data indicate that audio-visual integration is very different from the previous models developed in barn owls. We expect to find computational mechanisms that allow sufficient behavioral precision even without the peripheral structures that were previously thought to be indispensable.

虽然鸟类的空间视觉已经被很好地理解，但对于大多数鸟类物种来说，空间听觉处理仍然令人困惑。尽管大多数鸟类在一个高度结构化的世界中在所有三个维度上移动，但人们认为大多数鸟类的听觉定位仅限于方位角，也就是说，仅沿水平维度沿着移动。确定声源高度的高度线索通常是由大多数鸟类不具备的外耳结构引入的;只有仓鸮等专业鸟类才有解剖学特征（如不对称的耳孔），允许在高度上定位。然而，最近的数据表明，球形鸟头诱导声学非线性，可能允许声音定位在海拔头部运动。我们将在一个受控的范例中研究鸡的这种行为，以确定非专业物种是否确实能够在所有维度中定位声音。此外，我们将探讨听觉信息是如何整合到视觉空间的地图在中脑视顶盖。如果听觉系统确实无法在高处定位声音，那么听觉信息又是如何整合到顶盖中视觉空间的精确地图中的呢？我们将记录中脑神经元在听觉、视觉和视听刺激下的反应，以确定每种方式的感受野并描绘整合规则。 初步数据表明，视听整合是非常不同的，从以前的模型中谷仓猫头鹰。我们希望找到计算机制，即使没有以前被认为是必不可少的外围结构，也能实现足够的行为精确性。