The role of neural variability in production and plasticity of birdsong

鸣禽的发声学习为研究感觉运动的一般机制提供了模型 与人类语音学习特别相关的学习。对鸣禽和人类来说， 听到别人的声音，以及自己的听觉反馈，在发声中起着核心作用。 学习我们以前的工作表明，基底神经节-前脑通路参与了 处理听觉反馈和驾驶经验依赖的变化发声。 此外，这些实验表明，从基底神经节回路引入到歌曲的变异性 运动结构和行为可能在歌曲可塑性中起关键作用。在这里，我们建议 为了进一步验证这一观点，我们将行为和神经方法结合起来， 歌曲产生的可变性和可塑性。我们将使用基底神经节的慢性记录 电路和歌曲运动结构在唱歌的鸟类，以表征正常水平的行为和 神经变异以及检查神经元-神经元和神经元-行为共变（Aim 1）。 然后，我们将在成年鸟类中使用反馈操作来驱动歌曲和学习的适应性变化 行为变异性和可塑性能力之间的关系（目标2）。最后我们将 监测和操纵活动（通过慢性记录和病变）在条件适应 可塑性，以研究神经变异性产生的机制及其 行为改变（Aim 3）。鸣禽提供了一个系统， 对明确定义和可量化行为的基于绩效的反馈可能会 在机械的层面上理解。这样的理解将提供基本的洞察力正常 学习过程，并有助于我们预防和纠正残疾， 这些过程的障碍。

Vocal learning by songbirds provides a model for studying general mechanisms of sensorimotor learning with particular relevance to human speech learning. For both songbirds and humans, hearing the sounds of others, and auditory feedback of oneself, plays a central role in vocal learning. Our previous work suggests that a basal ganglia-forebrain pathway participates in processing auditory feedback and in driving experience-dependent changes to vocalizations. Moreover, these experiments suggest that variability introduced from basal ganglia circuitry to song motor structures and behavior may play a crucial role in enabling song plasticity. Here, we propose to further test this idea by combining behavioral and neural approaches to study contributions of variability to song production and plasticity. We will use chronic recordings from basal ganglia circuitry and song motor structures in singing birds to characterize normal levels of behavioral and neural variation as well as to examine neuron-neuron and neuron-behavior co-variation (Aim 1). We will then use feedback manipulations in adult birds to drive adaptive changes in song and study the relationship between behavioral variability and the capacity for plasticity (Aim 2). Finally, we will monitor and manipulate activity (via chronic recordings and lesions) during conditions of adaptive plasticity to investigate mechanisms underlying the generation of neural variability and their requirement for behavioral change (Aim 3). Songbirds provide a system where the influence of performance-based feedback on a well-defined and quantifiable behavior potentially can be understood at a mechanistic level. Such an understanding will provide basic insight into normal learning processes and contribute to our ability to prevent and correct disabilities that arise from dysfunction of these processes.