Functional neural circuitry for decision making in the superior colliculus

项目摘要(摘要) 这项拟议的研究的长期目标是了解控制精神障碍的神经机制。 正常和病理条件下的运动输出。我们在这里研究功能电路是如何在 上丘(SC)是一种双侧中脑结构，已知对定向行为很重要， 有助于做出关于运动的决定。中心假设是空间目标之间的竞争 在两个SCs中的代表是由参与局部抑制的连合SC神经元介导的。我们对此进行测试 通过记录和操纵自由移动转基因中特定类别神经元的活动来提出假说 执行嗅觉提示空间选择任务的小鼠。目标1将检查一个SC内的活动如何 兴奋性和抑制性SC神经元，在不同的小鼠组中被检测，是空间选择的基础。目标2将 检查这种活动，以及抑制对同一SC内兴奋性SC活动的影响 由两个SC代表的空间目标之间的竞争调制。目标3将考察 连合的SC神经元参与了空间靶点之间的这种竞争。如果成功，总体影响 我们的建议将阐明兴奋性和抑制性SC神经元如何相互作用-在一个SC和 在两个SC之间--调解空间选择，这是决策的重要形式。除了测试之外 这里提出的具体假设，我们开发的模型将使未来的研究成为可能 其他基因定义的神经元网络对运动的决定也有贡献。最终， 了解正常的运动控制有助于改进运动障碍的治疗方法，例如 帕金森氏症。

PROJECT SUMMARY (ABSTRACT) The long-term goal of the proposed research is to understand the neural mechanisms underlying the control of motor output under normal and pathological conditions. We examine here how functional circuitry in the superior colliculus (SC), a bilateral midbrain structure known to be important for orienting behaviors, contributes to decisions about movements. The central hypothesis is that competition between spatial targets represented in the two SCs is mediated by commissural SC neurons that engage local inhibition. We test this hypothesis by recording and manipulating the activity of specific classes of neurons in freely-moving transgenic mice performing olfactory-cued spatial choice tasks. Aim 1 will examine how the activity within one SC of excitatory and inhibitory SC neurons, examined in separate sets of mice, underlies spatial choice. Aim 2 will examine how this activity, and the influence of inhibition on excitatory SC activity within the same SC, is modulated by competition between spatial targets represented by the two SCs. Aim 3 will examine the role of commissural SC neurons in mediating this competition between spatial targets. If successful, the overall impact of our proposal will be the elucidation of how excitatory and inhibitory SC neurons interact – within one SC and between the two SCs – to mediate spatial choice, an important form of decision making. In addition to testing the specific hypotheses proposed here, the model we develop will make possible future research into how other genetically-defined networks of neurons contribute to decisions about movements. Ultimately, understanding normal motor control can contribute to improving therapies for movement disorders, such as Parkinson's disease.