Meeting Abstract
The extraordinary aerial agility of flies is achieved primarily through the action of 12 pairs of muscles, each innervated by a single motorneuron. A structurally complex wing hinge transforms changes in tension within steering muscles into subtle alterations in wing kinematics, which in turn regulate aerodynamic forces and moments. Understanding this complex transformation between muscle action and wing motion is an essential goal in determining both the neurobiological and biomechanical basis of flight. Our approach is to record the wing motion of tethered flies using high-speed videography while simultaneously capturing changes in muscle activation as reported by a genetically encoded calcium indicator. We use the Gal4/UAS system to express GCaMP6f within the steering muscles and machine vision approaches to determine the time history of activity within each motor unit. By presenting translational and rotational optic flow patterns to the fly, we elicit a variety of virtual maneuvers while capturing wing kinematics with three high-speed cameras. Correlating time history of muscle activation to the wing kinematics yields a model of how the steering muscles control the full 3-dimentional motion of the wing. We plan to combine our analysis with existing data on free flight maneuvers to develop a more comprehensive model of flight control that links muscle activity to body motion.
