Crossmodal visual input for odor tracking during fly flight.
Flies generate robust and high-performance olfactory and visual behaviors. Adult fruit flies can distinguish small differences in odor concentration across antennae separated by less than 1 mm [1], and a single olfactory sensory neuron is sufficient for near-normal gradient tracking in larvae [2]. During flight a male housefly chasing a female executes a corrective turn within 40 ms after a course deviation by its target [3]. The challenges imposed by flying apparently benefit from the tight integration of unimodal sensory cues. Crossmodal interactions reduce the discrimination threshold for unimodal memory retrieval by enhancing stimulus salience [4], and dynamic crossmodal processing is required for odor search during free flight because animals fail to locate an odor source in the absence of rich visual feedback [5]. The visual requirements for odor localization are unknown. We tethered a hungry fly in a magnetic field, allowing it to yaw freely, presented odor plumes, and examined how visual cues influence odor tracking. We show that flies are unable to use a small-field object or landmark to assist plume tracking, whereas odor activates wide-field optomotor course control to enable accurate orientation toward an attractive food odor.
Duistermars
Brian J
BJ
Department of Physiological Science, University of California, Los Angeles, California 90095-1606, USA.
Frye
Mark A
MA
D000818:Animals; D001070:Appetitive Behavior / Q000502:physiology*; D004331:Drosophila melanogaster / Q000502:physiology*; D005260:Female; D005426:Flight, Animal / Q000502:physiology*; D009812:Odorants; D012903:Smell / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*