The work in this project investigates how insects cope with fast image motion during flight. Insects use their brains to coordinate quick and accurate aerial maneuvers, but with coarse eyes that are immovably fixed in their heads, they cannot stabilize images the way humans do. The result is significant motion blur of objects they need to see in order to fly. How insect brains can so quickly gather information from a fast-moving image, then process it to generate appropriate flight responses, is an important, unresolved problem in visual science. These experiments study the steering efforts of tethered and freely flying fruit flies as they are presented with moving images under increasingly challenging circumstances, such as dim light and low contrast. The results will contribute to better understanding animal flight, human vision, and improve the performance of autonomous robots, such as flying drones. This project produces outreach and training opportunities to impact underrepresented groups through three activities. First, training undergraduates at Florida International University, most of whom identify from traditional minority groups, to carry out some of the laboratory work. Second, hosting in the lab at-risk local high school students from a non-profit organization that aims to inspire at-risk and delinquent youth. Third, demonstrating a portable version of these experiments to the Miami Science Museum's annual Brain Fair, a community outreach event with local neuroscientists directed at teaching brain and behavioral sciences to children in the broader Miami area.
The goal of this work is to determine the consequences of photon noise that is coupled to self-motion, and reveal the neural and behavioral mechanisms flies use to counteract its effects. The discrete and random nature of light absorption dictates that when photons are scarce, images suffer from low signal to noise ratios. This occurs whenever light intake is limited, such as when the environment is dim, or when eyes are physically small, or when objects move quickly across the visual field, which is often an inevitable result of quick flight. This project aims to determine how the fruit fly nervous system contends with degraded images just when it needs accurate visual information to coordinate responsive aerial movements. Tethered flies will view quickly moving projected patterns, which will establish the relationship between flow-induced photon noise, regional acuity, and attention. In the next stage, freely flying flies moving through obstacles will help determine the trade-offs of flight-induced noise and steering decisions, in other words the behavioral strategies that address and possibly minimize flow induced signal noise. And finally, sharp electrode elecrophysiological recordings will characterize spatial and temporal responses in early visual neurons while they view fast-moving patterns, which will then form the basis of biological models for viewing fast optic flow. The results of this project will offer neurobiological insight to the study of visual performance in moving animals, and practical insight to the design of artificial visual systems.
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.
