Behavioral and Neural Analysis of Vocal Plasticity

摘要 鸣禽的发声学习为研究鸟类如何使用基于表现的反馈提供了一个有用的模型， 神经系统在校准和维持运动技能，特别是与人类语言相关。鸟鸣提供 一个良好的描述和量化的行为，是由一个离散的和广泛的调查， 一组大脑区域。歌曲学习分为两个阶段，这两个阶段都依赖于听觉[17，18]。第一、 在感官学习期间，幼鸟会聆听并记住成年“导师”的歌声。然后，在一段时间内， 在感觉运动学习的过程中，他们使用听觉反馈来逐渐完善自己最初散漫的发声， 它们逐渐类似于先前记忆的家教歌曲。正常的歌曲学习需要适当的 在早期发展的敏感时期，也依赖于成年后的听觉反馈来维持 精确校准的语音输出[4]。歌曲和语音依赖听觉反馈的相似性 这表明，对歌曲学习的研究可能会为行为和神经系统提供更全面的见解。 控制发声运动学习的机制。此外，我们特别感兴趣的是， 神经节-前脑回路（前前脑通路或“AFP”）在声乐学习中的作用。这条电路在以下方面起着核心作用： 幼鸟和成年鸟的反馈依赖性鸣唱学习。因为AFP可以在 在明确定义的行为背景下，它可能被证明是理解基底神经节功能的一个特别容易处理的模型 更普遍地说。在这里，我们建议使用的技术，我们开发的听觉反馈操纵 上一个资助周期扩展了我们对鸣禽发声行为如何由经验塑造的研究（目标1）， 确定驱动学习的信号如何在大脑中表达（目标2），以及它们如何参与基底神经节 改变歌曲的电路（目标3）。我们将重点放在孟加拉雀，一个物种，表现出的一般性质， 声音学习，但似乎特别依赖于听觉反馈。鸣禽提供了一个模型， 基于绩效的反馈对明确定义和可量化行为的影响可以在 机械水平。这样的理解将提供对正常学习过程的基本见解，特别是 与言语相关，并有助于我们预防和纠正这些功能障碍引起的残疾的能力。 流程.

Abstract Vocal learning in songbirds provides a useful model for studying how performance-based feedback is used by the nervous system in calibrating and maintaining motor skills, with particular relevance to human speech. Birdsong offers the advantages of a well-described and quantifiable behavior that is subserved by a discrete and extensively investigated set of brain regions. Song learning proceeds in two stages, both of which depend critically on hearing [17, 18]. First, during a period of sensory learning, young birds listen to and memorize the song of an adult 'tutor'. Then, during a period of sensorimotor learning, they use auditory feedback to gradually refine their own initially rambling vocalizations so that they progressively resemble the previously memorized tutor song. Normal song learning requires appropriate experience during a sensitive period in early development, and also relies on auditory feedback in adulthood to maintain precisely calibrated vocal output [4]. The similarities between song and speech in their reliance on auditory feedback suggest that investigations of song learning may provide more general insights into the behavioral and neural mechanisms that govern vocal-motor learning. In addition, we are especially interested in the function of an avian basal ganglia-forebrain circuit (the anterior forebrain pathway or 'AFP') in vocal learning. This circuit plays a central role in feedback-dependent song learning in juvenile and adult birds. Because the AFP can be studied mechanistically in the context of well-defined behavior it may prove to be a particularly tractable model for understanding basal ganglia function more generally. Here, we propose to use the techniques for auditory feedback manipulation that we developed under the previous grant cycle to extend our studies of how vocal behavior in songbirds is shaped by experience (aim 1), determine how the signals that drive learning are represented in the brain (Aim 2) and how they engage basal ganglia circuitry to change song (Aim 3). We will focus on the Bengalese finch, a species that exhibits general properties of vocal learning, but appears to rely particularly strongly on auditory feedback. Songbirds provide a model where the influence of performance-based feedback on a well-defined and quantifiable behavior can be understood at a mechanistic level. Such an understanding will provide basic insight into normal learning processes, with particular relevance to speech, and contribute to our ability to prevent and correct disabilities that arise from dysfunction of these processes.