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.
