Functional neural circuitry for decision making in the superior colliculus

项目概要（摘要） 这项研究的长期目标是了解控制大脑皮层的神经机制。 正常和病理条件下的运动输出。我们在这里研究如何在功能电路 上级丘（SC），一种已知对定向行为很重要的双侧中脑结构， 对运动的决定有影响。核心假设是空间目标之间的竞争 在两个SC中代表的是由参与局部抑制的连合SC神经元介导的。我们测试这个 通过记录和操纵自由移动的转基因动物中特定类别神经元的活动， 执行嗅觉提示空间选择任务的小鼠。目标1将研究一个供应链内的活动如何 兴奋性和抑制性SC神经元，在单独的小鼠组中检查，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， 通过由两个SC代表的空间靶标之间的竞争来调节。目标3将审查 连合SC神经元介导空间靶点之间的竞争。如果成功， 我们的建议将是阐明兴奋性和抑制性SC神经元如何相互作用-在一个SC内， 在两个SC之间-调解空间选择，决策的一种重要形式。除了测试 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， 其他遗传定义的神经元网络有助于关于运动的决定。最后， 了解正常的运动控制有助于改善运动障碍的治疗， 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.