Binaural Neural Processing in the Auditory Midbrain

听觉依赖于大脑。我们的长期目标是确定来自环境的声音如何在大脑中产生的电信号中表现出来，以及这种表现如何依赖于神经回路、神经化学物质和神经生理过程。我们未来五年的短期目标是研究一个与听力相关的关键大脑结构——下丘是如何整合从两只耳朵获得的信息的。******来自自然环境的声音会冲击左右耳，分别在耳朵上产生两种刺激。这两种刺激的强度和时间取决于声音的位置。对两只耳朵的刺激会在左右听觉神经通路中产生两组信号。这些信号被下丘和其他听觉处理中心的神经元整合，这样大脑就可以测量声音的特征，包括它的空间位置。******当环境中存在多种声音时，每种声音都会在听觉神经通路中引发信号。不同声音发出的信号的整合使得对一种声音的反应依赖于另一种声音，这可以极大地影响对每种声音的感知。在我们的研究中，我们将发现前一个声音如何产生后效，从而影响神经元对后一个声音的反应。我们将确定这种余波是如何依赖于声音之间的空间关系的。我们将发现这种依赖是如何产生的，作为来自左右通路的神经信号整合的结果。******这只老鼠将被用作动物模型，因为它有敏锐的听觉。对其听觉系统有了丰富的基础知识。大鼠与许多其他哺乳动物共享基本的听觉神经机制。对大鼠的进一步研究可以使我们全面了解该物种的听觉机制，这将极大地促进对哺乳动物听觉机制的理解。我们选择关注下丘，因为现有证据表明，该结构中的神经元对处理与音质、时间和位置相关的信息很重要。******我们的研究结果将帮助我们理解听觉重要方面的神经机制，如声音的定位和单个声音的分离。将我们的结果与现有文献进行比较，将使我们能够确定不同哺乳动物物种共有的听觉机制。因此，本研究将对听觉神经科学领域的发展起到重要的推动作用。从这项研究中产生的关于空间声线索时间变化的神经处理的知识可以在未来被工程师应用于开发智能听力增强设备。除了产生基本的科学知识外，这项研究还将为学生提供必要的培训，帮助他们成为未来神经科学研究的领导者。

Hearing is dependent on the brain. Our long-term goal is to determine how sounds from an environment are represented in electrical signals generated in the brain and how the representation is dependent on neural circuits, neurochemicals, and neurophysiological processes. Our short-term goal for the next five years is to investigate how a key hearing-related brain structure named the inferior colliculus integrates information obtained at the two ears.******A sound from an natural environment can impinge on the left and right ears and generate two stimuli at the ears, respectively. The strengths and timing of the two stimuli are dependent on the location of the sound. Stimulation of the two ears leads to two sets of signals in the left and right auditory neural pathways. These signals are integrated by neurons in the inferior colliculus and other auditory processing centres, so that characteristics of the sound including its spatial location can be gauged by the brain.******When multiple sounds exist in an environment, each sound can elicit signals in the auditory neural pathways. Integration of signals elicited by different sounds makes the response to one sound depend on the other, which can greatly affect the perception of each sound. In our research, we will find how a preceding sound generates an aftereffect to shape the response of a neuron to a subsequent sound. We will determine how such an aftereffect is dependent on the spatial relationship between the sounds. We will discover how this dependence is generated as a result of integration of neural signals from the left and right pathways.******The rat will be used as an animal model, as it has a keen sense of hearing. Abundant basic knowledge has been obtained about its auditory system. The rat shares basic auditory neural mechanisms with many other mammals. Further research using the rat can enable us to fully understand hearing mechanisms in this species, which will greatly benefit the comprehension of hearing mechanisms in mammals in general. We choose to focus on the inferior colliculus as existing evidence indicates that neurons in this structure are important for the processing of information related to sound quality, timing, and location.******Results from our research will help us understand neural mechanisms underlying important aspects of hearing such as localization of sounds and segregation of individual sounds. Comparing our results with existing literature will allow us to identify hearing mechanisms shared by different mammalian species. Thus, this research will significantly advance the field of auditory neuroscience. Knowledge generated from this study about neural processing of temporal changes of spatial acoustic cues can be applied in the future by engineers to develop intelligent hearing-enhancing devices. In addition to generating basic scientific knowledge, this research will provide essential training to students to help them become future leaders in neuroscience research.