NSF-IOS-BSF: Mechanisms of Motor Expression of a Decision

动物和人类在追求生存和繁殖的目标时，无论是寻找配偶，逃离捕食者，还是吃饭，都必须不断地对不断变化的环境做出反应。为了使这成为可能，身体和神经系统必须共同努力，产生适当的行为。最近的研究表明，神经系统不是使用指定反应的所有细节并设定固定目标的中央控制，而是根据生物体的内部状态和直接的环境背景“在飞行中”产生适当的运动反应，这些反应可能随着动物的行为而改变，部分原因是动物自己的行为。通过在实验分析中易于处理的动物身上研究这个问题，将有可能找出这些快速、灵活和适应性行为变化背后的详细神经回路，并在动物行为时跟踪回路活动的变化。要做到这一点，需要开发新的技术，使记录和控制行为过程中许多神经元的活动成为可能。由此产生的技术可能会对新型脑/计算机接口的发展产生广泛的影响，这可能会导致新的假肢设备。同时，研究适应灵活行为的神经回路的细节将为创造生物启发机器人的灵活控制提供设计。这项研究将培养能够解决跨学科问题的学生，并有可能吸引学生从事科学和技术领域的职业。对无脊椎动物、脊椎动物和人类脊髓运动控制的研究表明，运动控制不是一个由中央控制器选择运动反应的层次结构，而是一个根据生物体的内部状态和直接环境背景增加或去除运动成分的层次结构。为了确定运动部件是如何动态组装的，当动物以海藻为食时，将分析加利福尼亚海陆软体动物的神经回路，这些海藻会以变化的机械负荷挑战它们。电路将在完整的动物、减少喂食的准备和孤立的神经系统中进行研究。微电极阵列将利用细胞外记录分析神经活动模式的整体变化。在与密歇根大学NeuroNex中心的合作中，一种新型神经节界面将使用生物相容性的玻璃碳纤维电极开发，可以从细胞外和细胞内的多个位置进行记录。这些纤维将被改造，使它们也能控制神经元的活动。由此产生的设备可以为完整的、行为正常的动物的神经控制创造新的接口。将开发一个神经力学模型来预测关键识别神经元的活动变化如何影响力输出。柔性电机控制的新颖电路设计将在生物启发的软体机器人中实现。最后，这个项目将被用来吸引本科生和高中生进行科学和工程的跨学科研究。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Animals and humans must continually respond to a changing environment while pursuing the goals that allow them to survive and reproduce, whether they are seeking a mate, fleeing a predator, or eating a meal. To make this possible, the body and the nervous system must work together to generate appropriate behavior. Rather than using a central control that specifies all details of the responses and sets a fixed goal, recent studies suggest that nervous systems generate appropriate motor responses "on the fly" based on the internal state of the organism and the immediate environmental context, which may change as the animal acts, in part due to the animal's own behavior. By studying this problem in an animal that is tractable to experimental analysis, it will be possible to work out the detailed neural circuitry that underlies these rapid, flexible and adaptive changes in behavior, and to track changes in circuit activity as an animal behaves. To do this, novel technology will be developed that makes it possible to record and control the activity of many neurons during behavior. The resulting technology could have a broad impact on the development of novel brain/computer interfaces, which could lead to new prosthetic devices. At the same time, working out the details of neural circuitry for adaptive, flexible behavior will provide designs for creating flexible control of biologically-inspired robots. The research will train students who can solve interdisciplinary problems, and is likely to attract students to careers in science and technology.Studies of motor control in invertebrates and in the spinal cord of vertebrates and humans suggest that motor control is not a hierarchy in which a central controller selects motor responses, but a heterarchy in which motor components are added or removed depending on an organism's internal state and the immediate environmental context. To determine how motor components are dynamically assembled, the neural circuity of the marine mollusk Aplysia californica will be analyzed as animals feed on seaweed that challenges them with changing mechanical loads. Circuitry will be studied in intact animals, in a reduced feeding preparation, and in the isolated nervous system. A microelectrode array will analyze overall changes in patterns of neural activity using extracellular recordings. In collaboration with the NeuroNex hub at University of Michigan, a novel ganglion interface will be developed using biocompatible glassy carbon fiber electrodes, which can record from multiple sites both extracellularly and intracellularly. The fibers will be modified to allow them to control neuronal activity as well. The resulting device could create novel interfaces for neural control in intact, behaving animals. A neuromechanical model will be developed to predict how changing activity of key identified neurons affects force output. Novel circuit designs for flexible motor control will be implemented in biologically-inspired soft robots. Finally, this project will be used to attract undergraduates and high school students into interdisciplinary research in science and engineering.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.