Roy Ritzmann - US grants

Neural systems are organized to assimilate large amounts of sensory information and utilize it in making choices that result in meaningful behaviors. How such choices are made is central to understanding the function of any of these systems, whether they be complex processing centers such as the mammalian visual system or more simple invertebrate motor control systems. Several escape systems have served as useful models for studying this problem, because of various technical advantages which they offer. Although the neurons that make up an escape system must quickly process large amounts of sensory information in order to identify and react to a potential threat, the complete cellular analysis of the underlying circuitry is a very real possibility. The experiments described in this proposal are designed to take advantage of a particularly useful escape system, that of the american cockroach. The advantages of this system as a model include numerous large identifiable cells, (including the giant interneurons), and a resultant behavior that while reasonably complex is sufficiently predictable to allow extensive quantification. The recent discovery of a group of large thoracic interneurons that are post-synaptic to the giant interneurons means that a complete understanding of the decision making processes at the cellular level may now be possible. Our specific aims are to: (1) determine the manner in which directional sensory information carried in the giant interneurons is deciphered and used to control the directional escape movements, (2) determine the differences between two separate input pathways (the dorsal and ventral giant interneurons) and how one pathway is chosen over the other, and (3) determine the manner in which sensory information from thoracic appendages is used to influence the escape circuitry. All of these objectives will be pursued using intracellular analysis and dye injection techniques. Our hope is that these studies will generate principles regarding the manner in which nervous systems process sensory information and make meaningful decisions important to specific behaviors. Such principles may ultimately be generalized to more complex vertebrate systems which must solve similar problems.

This Integrative Graduate Education and Research Training (IGERT) award supports the establishment of a multidisciplinary graduate training program of education and research merging four existing research groups into a new entity with broad technical expertise yet still sharing a focus on Neuro-mechanical systems. Each existing group has a history of collaboration between various engineering fields and the biological sciences. However, meaningful interactions only came after considerable effort to overcome barriers. The training program will provide a formal process to help graduate students proceed through that process quickly and efficiently. Students in the training program will participate in cross-disciplinary courses and rotate through laboratories in all four fields. A multidisciplinary seminar featuring extended visits from leaders in each field will draw students together. Funds will permit travel to scientific meetings and workshops in each field. A common computer facility and office area will maintain interactions beyond the classroom. Internships in clinical and industrial settings will also be available as options. We have also planned an aggressive recruitment program emphasizing institutions committed to training students in underrepresented groups. Our trainees will graduate with appropriate tools and background necessary to work efficiently in teams. We believe that such an experience will pay great dividends to both the students and the disciplines in which they choose to work.

IGERT is an NSF-wide program intended to facilitate the establishment of innovative, research-based graduate programs that will train a diverse group of scientists and engineers to be well-prepared to take advantage of a broad spectrum of career options. IGERT provides doctoral institutions with an opportunity to develop new, well-focussed multidisciplinary graduate programs that transcend organizational boundaries and unite faculty from several departments or institutions to establish a highly interactive, collaborative environment for both training and research. In this second year of the program, awards are being made to twenty-one institutions for programs that collectively span all areas of science and engineering supported by NSF. This specific award is supported by funds from the Directorates for Biological Sciences, for Engineering, for Computer and Information Science and Engineering, and for Education and Human Resources.

Animals as simple as cockroaches and slugs and as complex as humans all possess similar ways to control how they walk, crawl, swim or fly through earth's many complex environments. Engineers have turned to these natural systems for inspiration in developing robots, hoping to attain the same ease of movement and ability to adapt to any environment on earth (or off of it). The goals of animal motion studies and robotics are clearly complementary and benefit greatly from extended interaction. Although many meetings have limited sessions dedicated to such discussions, the International Symposium on Adaptive Motion in Animals and Machines (AMAM) is uniquely dedicated to intense week long interaction among engineers and biologists. The funds from this proposal will be used to bring young U.S. scientists and engineers (especially female and underrepresented minorities) to AMAM 2008 this June 1-6 at Case Western Reserve University in Cleveland, Ohio. Funds will also be used to support web-based distribution of the meeting to members of the international community and educators who cannot attend the meeting in person. The potential impacts of this meeting include: 1) use of robots as hardware models to promote a greater understanding of how animals (including humans) control their movement through their complex worlds, 2) creation of new walking, crawling, swimming and flying robots that more closely capture properties of animals, and 3) introduction of young developing scientists and engineers to an area of research that relies heavily on collaboration of people with many different skills from many different areas for success. The ultimate goal of this work is to provide highly functional robotic devices to serve human needs, such as search and rescue, environmental monitoring, surveying and many others, as well as greater understanding of animal movement.

This project will examine neural circuits that make up a unique region of the insect brain, called the central complex, and will study its role in guiding the insect as it turns to move around barriers. This large midline brain region appears to be involved in processing large amounts of sensory information, then using it to influence movement. The Ritzmann laboratory will employ a range of electrophysiological and behavioral techniques to examine how central complex circuits process mechanical and visual information from antennae and eyes and to identify the neurons that perform these functions. Regions of the central complex will then be reversibly inactivated with local anesthetics to examine their effects on behavior. The results are critical to our understanding of how brain systems influence complex movements. They will complement recent advances in motor control stemming from neurogenetic techniques from several other laboratories. Indeed, because similar interactions between higher brain systems and local reflexes exist in virtually all legged animals, including vertebrates, the results will have wide ranging neurobiological impact. Moreover, the PI has a long-term commitment to bringing knowledge of biological systems to the design of legged robots. As such, the project should also lead to more advanced robots that can move autonomously through tortuous terrain with less direction from a driver. The project will continue the PI?s successful record of training both graduate and undergraduate students and extend this opportunity to pre-college students. Undergraduate and pre-college students will have the opportunity to work directly with graduate students and other senior laboratory personnel on the project under the direct guidance of Dr. Ritzmann. This arrangement generates a unique opportunity for novices to experience research while providing mentorship experience for the senior personnel.