Object tracking in motion-blind flies

In response to the movement of its visual world, Drosophila is capable of optomotor response in head and body turning, as well as a visual fixation response. This study shows that blocking the visual pathway activity responsible for optokinetic response in flies does not affect the visual fixation response, suggesting two distinct pathways for processing each set of information. By doing so, the authors also devised a neural and behavioral hierarchy in fly visual system where fixation behavior and the neurons mediating fixation response are upstream of optokinetic response as performed by lobula plate neurons.