Neural Analysis of Vocal Learning

描述：（改编自申请人摘要）：本项目的长期目标 研究的目的是了解学习和记忆的神经基础，特别是 大脑如何在感官信息的引导下学习复杂的运动行为。 鸣禽的发声学习为这一目的提供了一个有用的模型系统， 与人类语音学习特别相关。鸣禽学会了 在"感觉运动"期间，先前记忆的导师歌曲的副本 学习，他们使用自己声音的听觉反馈来改进 他们的声音输出，直到它匹配记忆的歌曲。这里提出的工作 专注于大脑系统中专门负责唱歌的区域 学习和生产，一个专门的皮质基底神经节电路称为 前前脑通路（AFP），因为它起着至关重要的作用， 在歌曲学习和成人声音可塑性中的作用还不清楚。 此外，皮质-基底神经节回路， 进化上，被认为在运动和强化学习中起作用， 许多脊椎动物，并成为一个关键的网站功能障碍，在一些 神经精神障碍因为鸣鸟AFP是一种离散的 皮质-基底神经节回路控制特定的行为，这可能证明 特别是易于处理的系统，用于阐明 这种途径，无论是正常的还是疾病。 APP在学习过程中发展了歌曲选择性听觉反应， 运动相关的活动在唱歌，但如何这些感官和运动 相互之间的关系并不清楚。这个回路中的活动也是 在不同的审判中变化很大，这就提出了一个问题， 可靠地编码信息或引导歌曲。同时记录了 多个神经元在输出核的APP，LMAN，在这两个唱歌， 和歌曲播放，第一个目标将测试的假设，该应用程序编码 相关歌曲和唱歌相关信息的形式， "人口"代码。进一步的假设是APP神经元的特定模式 活动对正常的歌曲发展至关重要，也许可以指导 发声运动核RA中的连接的形成。这将受到考验 同时记录LMAN和RA中的神经元， 他们的活动的协方差以及它与声音输出的关系可以是 分析了LMAN-RA相互作用将首先在正常鸟类中进行研究， 不同的学习阶段，然后在AFP活动中断后， 模式，在方式上，将阐明正常的突触处理内 APP，以及这个回路如何影响歌曲运动通路。

DESCRIPTION: (Adapted from applicant's abstract): The long-term goal of this research is to understand the neural basis of learning and memory, especially how the brain learns complex motor behaviors, guided by sensory information. Vocal learning in songbirds provides a useful model system for this purpose, with special relevance to human speech learning. Songbirds learn to produce a copy of a previously memorized tutor song during a period of "sensorimotor" learning, in which they use auditory feedback of their own voice to refine their vocal output until it matches the memorized song. The work proposed here focuses on a particular part of the system of brain areas devoted to song learning and production, a specialized cortical-basal ganglia circuit known as the anterior forebrain pathway (AFP), because it plays a crucial but ill-understood role both in song learning and in adult vocal plasticity. Moreover, cortical-basal ganglia circuits, which are well conserved evolutionarily, are thought to function in motor and reinforcement learning in many vertebrates, and to be a critical site of dysfunction in a number of neuropsychiatric disorders. Because the songbird AFP is a discrete cortical-basal ganglia circuit controlling a specific behavior, it may prove a particularly tractable system for elucidating the very general functions of such pathways, both normally and in disease. The APP develops song-selective auditory responses during learning, and shows motor-related activity during singing, but how these sensory and motor responses relate to each other is not clear. Activity in this circuit is also very variable from trial to trial, raising the question of how it could reliably encode information or guide song. With simultaneous recordings from multiple neurons in the output nucleus of the APP, LMAN, during both singing and song playback, the first aim will test the hypothesis that the APP encodes relevant song- and singing-related information in the form of a distributed "population" code. A further hypothesis is that specific patterns of APP neural activity are critical for normal song development, perhaps guiding the formation of connections in the vocal motor nucleus RA. This will be tested with simultaneous recordings of neurons in both LMAN and RA, so that the covariance of their activity and how it relates to vocal output can be analyzed. LMAN-RA interactions will be studied first in normal birds at different stages of learning, and then after disruptions of the AFP activity pattern, in ways that will shed light both on normal synaptic processing within the APP, as well as on how this circuit influences the song motor pathway.