Meeting Abstract
Flying insects acquire, process and respond to stimuli of multiple modalities at a time scale of a few wing beats to maintain stable flight. Of the various sensory inputs, antennal mechanosensory input and visual input have been shown to be critical for flight in hawk moths. Acquisition and processing of visual inputs is typically slower than that of mechanosensory inputs. How the stimuli from different modalities across different time scales are combined for stable flight is not well understood. We have addressed this question, in the Oleander hawk moth (Daphnis nerii) by recording the electrophysiological activity from single descending neurons in the neck connective, while providing the moth various combinations of visual and antennal mechanosensory inputs. These recordings allowed us to identify multiple classes of descending neurons which respond either to only visual stimuli or only antennal mechanosensory stimuli, or both visual and mechanosensory stimuli. There is a clear bandwidth separation in the neurons’ response to the visual and antennal mechanosensory stimuli. Neurons responding to antennal mechanosensory stimuli alone are high-pass and encode at frequencies exceeding wingbeat frequency, whereas neurons responding solely to visual stimuli are low-pass and encode at lower frequency visual stimuli. We classified the descending neurons by algorithmically creating circuit models to explain the responses and grouping neurons with similar circuit models. These diverse classes likely correspond to information used in different flight stabilization scenarios.
