Meeting Abstract
Flying fruit flies must compensate for the visual limitations of their tiny compound eyes. Their small light-capturing aperatures admit little light, and this gets worse during flight, when images move rapidly over the retina and reflect little light to any one spot. This is especially problematic in the faster regions of the visual field, perpendicular to the direction of flight, but could be ameliorated by shifting attention forward, to slower regions of the flow field. To test for attention shifts, we measured steering responses of rigidly tethered flies during simulated forward flight in a visual arena. We found that as forward speed increased, fruit flies responded more strongly to turning cues presented directly in front, and largely ignored cues presented out to the sides. These results are consistent with a shift in attention from peripheral to forward regions, in response to high speed forward motion. We further tested if such shifts could affect other regions for other direction of optic flow, but found attention shifts only in the forward direction. This may be an adaptation to the normal flight patterns, which are characterized by long forward bouts of flight with intermittent saccades. Because the processing that mediates the attention shift seems to be direction-agnostic, the response may be trading off directional-selectivity for high-speed performance.
