The rodent vibrissal-trigeminal system is one of the most important models in neuroscience for the study of sensorimotor integration. To date, however, research has focused exclusively on direct tactile sensation. Recent results from the Hartmann and Gopal laboratories have demonstrated that rat vibrissae have a robust and repeatable mechanical response to airflow. In addition, neurons in the vibrissal-trigeminal system are known to respond to air puffs. These results suggest that the rat may use its vibrissae to detect air currents and determine wind direction. The Northwestern-Elmhurst team will perform mechanical, behavioral, and computational studies to characterize the role of vibrissae in wind-following behaviors, and the vibrissal-related neural response to air currents. These will constitute some of the first investigations of the underlying mechanisms that permit terrestrial mammals to sense and follow the wind. The team will specifically identify the morphological features of vibrissae and their orientation on the mystacial pad that enable flow sensing behaviors. They will investigate the broad hypothesis that differential mechanical deformations of the vibrissae across the mystacial pad can encode a variety of flow parameters. Finally, behavioral experiments will be performed to determine the extent to which the rat uses its vibrissae to sense airflow, and to quantify the movement strategies used during anemotaxis in the behaving animal. The partnership between Northwestern and Elmhurst will provide significant research opportunities for undergraduates; in addition, videos will be developed to teach the fundamental principles of fluid dynamics and biological sensing that underlie this research. The proposed work has potentially large implications for olfactory localization and the structure of the olfactory system, and is likely to lead to the development of novel flow-sensing technologies.
