Synaptic and circuit mechanisms of learned vocal production

项目摘要/摘要 该项目旨在研究使习得的复杂行为成为可能的电路机制，例如 说乐器或演奏乐器。目前，这些产生的基础过程 人们对神经网络的行为序列知之甚少。具体地说，各种组织的贡献 这种网络行为的细胞类型仍未得到充分研究。在这里，我们考虑一种重要的电机控制 斑马雀的核团称为HVC(以前称为高音中枢)，它产生神经 在表演学来的求爱歌曲时的几个序列。我们目前的建议主要集中在当地 回路中间神经元，这是对这个网络的唯一抑制来源。有几款车型已经成为 有人建议解释抑制在歌曲制作中的作用，但共识仍然难以达成。为了测试这些 模型，我们提出了一系列电生理、成像和光遗传学研究，使我们能够 有选择地操纵和监测HVC中间神经元，通常是在歌曲产生的背景下。 在目标1中，我们将从突触后的角度研究抑制的作用。的主要关注点 本研究的目的是记录歌曲产生过程中HVC前运动神经元的抑制性突触电流。 在目标2中，我们将通过直接记录种群的活动来测量神经元间网络功能 在歌唱过程中辨认出的中间神经元。我们还将评估单个中间神经元对 网络使用解剖学和电生理学方法。 在目标3中，我们将使用体内和体外测量来表征HVC的遗传亚型。 并区分它们在网络中的角色。

Project Summary/Abstract This project aims to investigate the circuit mechanisms which enable learned complex behaviors, such as speaking or playing an instrument. At present, the processes which underlie the generation of these behavioral sequences by neural networks are poorly understood. Specifically, the contributions of various cell types to this network behavior remain underexplored. Here we consider an important motor control nucleus in the zebra finch called HVC (formerly known as the high vocal center), which produces neural sequences during the performance of the learned courtship song. Our present proposal focuses on local circuit interneurons, which represent the sole source of inhibition to this network. Several models have been proposed to explain the role of inhibition in song production, but consensus remains elusive. To test these models, we propose a series of electrophysiological, imaging, and optogenetic studies that will enable us to manipulate and monitor HVC interneurons selectively, often in the context of song production. In Aim 1, we will examine the role of inhibition from a postsynaptic perspective. The primary focus of this this aim is to record inhibitory synaptic currents in HVC premotor neurons during song production. In Aim 2, we will measure interneuron network function by directly recording the activity of populations of identified interneurons during singing. We will also gauge the impact of individual interneurons on the network using anatomical and electrophysiological methods. In Aim 3, we will use in vivo and in vitro measurements to characterize the genetic subtypes of HVC interneurons and to distinguish their roles within the network.