Auditory-Vocal Processing in a Behavioral Context

描述(由申请人提供)：使人类和其他几个物种能够使用学习的声音信号进行交流的神经生物学适应，例如语音，还没有被很好地理解。成像数据导致了一种观点，即语音不仅是偏侧的，而且还在用于声音对象识别的听觉(腹侧、颞叶)流中进行处理，以及在将声音映射到运动前发声区域的听觉-运动(背侧、额部)流中进行处理。在电路水平上对这一提议进行神经生物学研究需要建立一个参与发声学习的动物模型。目前的项目将使用鸣鸟模型来详细研究双流提议，因为1)鸣鸟是极少数动物类别中最容易研究的，这些动物学习像人类一样产生用于社会交流的声音信号；2)鸣鸟前脑的两个解剖和功能截然不同的区域似乎对歌曲进行了不同的处理，就像言语一样。我们建议开发一种新的范式，使用清醒和行为鸣禽，通过在听觉和声音运动前区域记录来评估暴露历史和行为显著对听觉加工的影响，这可能在复杂通信信号的知觉加工以及声音产生中发挥重要作用。为此，我们将使用三种方法在生理记录之前和期间操纵行为突显。1)鸟类将学习在行为范式中辨别其他个体独特的歌声，然后在双侧听觉和运动结构中进行急性多电极记录，以测试行为强化对训练刺激反应的影响2)长期植入以听觉和运动结构为目标的电极的鸟类将接受辨别训练，从而能够实时研究与行为学习相关的感觉处理的变化。3)提出了一种将辨别训练与头部固定鸟类的急性神经生理记录相结合的新方法。这将结合前两种方法的优点，在行为过程中从双侧不同的神经结构进行高质量的同时记录。这项拟议的工作在两个方面具有重要意义。首先，它的目的是利用现有的方法在行为过程中从听觉区域收集神经数据，并开发一种新的范例，在执行辨别任务时从清醒的鸣禽身上进行多电极记录。这种创新的方法将允许实时评估作为相关语音通信信号识别基础的听觉处理。其次，这些方法将首次实现在任务执行过程中同时从感觉结构和发声运动通路进行记录，这可能在仅在任务环境中揭示的知觉加工中具有重要作用，正如研究表明言语产生和知觉功能重叠所表明的那样。这将测试双流建议，并可能揭示与正常和异常语音处理相关的重要原则。

DESCRIPTION (provided by applicant): The neurobiological adaptations that enable humans and a few other species to communicate using learned vocal signals, e.g. speech, are not well understood. Imaging data have led to the proposal that speech is not only lateralized, but also processed both in an auditory (ventral, temporal) stream that serves acoustic object identification and in an auditory-motor (dorsal, frontal) stream that maps sounds onto pre-motor vocal areas. Neurobiological investigation of this proposal at the circuit level requires an established animal model that engages in vocal learning. The current project will use the songbird model to study the dual stream proposal in detail because 1) songbirds are the most easily studied of the very few animal taxa that learn to produce vocal signals for social communication as humans do; and 2) songs appear to be processed differently in two anatomically and functionally distinct areas of the songbird forebrain, as seems true for speech. We propose to develop a novel paradigm, using awake and behaving songbirds, to evaluate the effects of exposure history and behavioral salience on auditory processing by recording in both the auditory and vocal pre-motor areas, which may play an important role in perceptual processing of complex communication signals as well as in vocal production. To this end, we will manipulate behavioral salience before and during physiological recordings, using three approaches. 1) Birds will learn to discriminate the unique songs of other individuals in a behavioral paradigm, followed by acute multielectrode recording in auditory and motor structures bilaterally to test the effects of behavioral reinforcement on responses to training stimuli 2) Birds with chronically implanted electrodes that target auditory and motor structures will undergo discrimination training, enabling changes in sensory processing associated with behavioral learning to be studied in real time. 3) A novel method for combining discrimination training with acute neurophysiological recording in head-fixed birds will be developed. This will enable high quality simultaneous recording from different neural structures bilaterally during behavior, combining the strengths of the first two methods. The proposed work is significant in two ways. First, it aims to both exploit existing methods for collecting neural data from auditory areas during behavior and also to develop a novel paradigm for multielectrode recording from awake songbirds during performance of a discrimination task. This innovative approach will allow for real time assessment of the auditory processing that underlies the discrimination of relevant vocal communication signals. Second, these approaches will for the first time enable simultaneous recording during task performance from both sensory structures and the vocal motor pathway, which may have an important role in perceptual processing that is only revealed in a task context, as has been suggested by studies showing overlap of speech production and perceptual function. This will test the dual stream proposal and may reveal important principles relevant to both normal and abnormal speech processing.