The temporal resolution of binaural integration in the lateral superior olive and its implications for the electrical restoration of spatial hearing

外侧上橄榄双耳整合的时间分辨率及其对空间听力电恢复的影响

• 批准号: 279586062
• 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: Priority Programmes
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/279586062?language=en
• 关键词: temporal; resolution; binaural; integration; lateral

The precise temporal integration of synaptic inputs represents one of the fundamental principles of sensory processing in neuronal circuits. Particularly, in the auditory system, neurons in the brainstem detect differences in the arrival time between excitatory and inhibitory inputs on the scale of only microseconds to allow for the accurate localization of a sound source. This ability is essential both for human communication (e.g. attending to a conversation in a noisy environment such as a party) as well as navigation (e.g. crossing a busy road). Whereas we routinely perform these tasks in everyday life, the underlying neuronal mechanisms, particularly the temporal limits of this binaural integration and the role of inhibitory inputs, are still not fully understood. Yet a comprehensive knowledge about these aspects of auditory processing is highly desirable , both for the basic understanding of fast neuronal integration mechanisms and from a clinical perspective, as the restoration of sound localization remains one of the central obstacles of cochlear implants (CIs). Taking advantage of our rich expertise on mammalian auditory brainstem physiology and its phylogeny, we aim to investigate the role of inhibition in neuronal sound location processing, particularly the bounds of temporal precision of inhibition. Utilizing a conceptually novel approach, we will perform in vivo electrophysiological recordings in Mongolian Gerbils (Meriones unguiculatus) to characterize the functional resolution of synaptic inputs both in binaural integration neurons as well as their monaural input nuclei. In parallel to acoustic (i.e. naturalistic) stimulation, we will obtain a complementary data set employing electrical stimulation of the cochleae. This will not only allow us to assess the temporal resolution of binaural integration involving synaptic inhibition, but also to identify basic principles of fast information processing during electrical stimulation, which ultimately will contribute towards the physiological restoration of sound localization in CI users.

突触输入的精确时间整合代表了神经元回路中感觉处理的基本原理之一。特别地，在听觉系统中，脑干中的神经元检测兴奋性和抑制性输入之间的到达时间的差异，其尺度仅为微秒，以允许声源的准确定位。这种能力对于人类交流（例如在嘈杂的环境中参加谈话，如聚会）以及导航（例如穿过忙碌的道路）都是必不可少的。虽然我们在日常生活中经常执行这些任务，但其潜在的神经机制，特别是双耳整合的时间限制和抑制性输入的作用，仍然没有完全理解。然而，这些方面的听觉处理的全面知识是非常可取的，无论是从基本了解快速神经元整合机制，并从临床的角度来看，恢复声音定位仍然是人工耳蜗（CI）的中心障碍之一。利用我们在哺乳动物听觉脑干生理学及其发生学方面的丰富经验，我们旨在研究抑制在神经元声音定位处理中的作用，特别是抑制的时间精度范围。利用一种概念上新颖的方法，我们将在体内进行电生理记录在蒙古长爪沙鼠（长爪沙鼠）的特点，在双耳整合神经元以及它们的单耳输入核突触输入的功能分辨率。与声学（即自然）刺激平行，我们将获得采用耳蜗电刺激的互补数据集。这不仅使我们能够评估涉及突触抑制的双耳整合的时间分辨率，而且还可以确定电刺激期间快速信息处理的基本原理，这最终将有助于CI用户的声音定位的生理恢复。