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

动物和人类必须不断地对不断变化的环境做出反应，同时追求使它们能够生存和繁殖的目标，无论它们是在寻找配偶，还是为了躲避捕食者，还是在吃东西。要做到这一点，身体和神经系统必须共同努力，才能产生适当的行为。最近的研究表明，神经系统不是使用中央控制来指定反应的所有细节并设定固定的目标，而是根据有机体的内部状态和直接的环境背景产生适当的运动反应，这种反应可能会随着动物的行为而改变，部分原因是动物自己的行为。通过在易于实验分析的动物身上研究这个问题，将有可能找到这些快速、灵活和适应性行为变化背后的详细神经回路，并跟踪动物行为过程中回路活动的变化。为了做到这一点，将开发新的技术，使记录和控制许多神经元在行为过程中的活动成为可能。由此产生的技术可能会对新型脑/计算机接口的开发产生广泛影响，这可能会导致新的假肢设备。与此同时，为适应、灵活的行为制定神经电路的细节，将为创造受生物启发的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，并可能吸引学生从事科学和技术方面的职业。对无脊椎动物以及脊椎动物和人类脊髓中的运动控制的研究表明，运动控制不是中央控制器选择运动反应的层次结构，而是一种根据有机体的内部状态和直接环境背景来添加或移除运动部件的异类结构。为了确定马达部件是如何动态组装的，将分析海洋软体动物加州海兔的神经回路，因为动物以海藻为食，挑战它们不断变化的机械负荷。电路将在完整的动物身上、在减少喂养准备的情况下以及在隔离的神经系统中进行研究。微电极阵列将使用细胞外记录来分析神经活动模式的整体变化。与密歇根大学的NeuroNex中心合作，将使用生物兼容的玻璃纤维电极开发一种新型的神经节界面，它可以从细胞外和细胞内的多个位置进行记录。这些纤维将被修改，以允许它们也控制神经元的活动。由此产生的设备可以为完好无损、行为正常的动物的神经控制创造新的界面。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。用于柔性电机控制的新颖电路设计将在受生物启发的软机器人中实现。最后，这个项目将被用来吸引本科生和高中生参与科学和工程领域的跨学科研究。这个奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.