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Matheson, A. M. M.

Publications and source records attributed to Matheson, A. M. M..

2 recordsLinked to original sources

A neural circuit for wind-guided olfactory navigation

To navigate towards a food source, animals must frequently combine odor cues that tell them what sources are useful with wind direction cues that tell them where the source can be found. Where and how these two cues are integrated to support navigation is unclear. Here we identify a pathway to the Drosophila fan-shaped body (FB) that encodes attractive odor and promotes upwind navigation. We show that neurons throughout this pathway encode odor, but not wind direction. Using connectomics, we identify FB local neurons called h{Delta}C that receive input from this odor pathway and a previously described wind pathway. We show that h{Delta}C neurons exhibit odor-gated, wind direction-tuned activity, that sparse activation of h{Delta}C neurons promotes navigation in a reproducible direction, and that h{Delta}C activity is required for persistent upwind orientation during odor. Based on connectome data, we develop a computational model showing how h{Delta}C activity can promote navigation towards a goal such as an upwind odor source. Our results suggest that odor and wind cues are processed by separate pathways and integrated within the FB to support goal-directed navigation.

neuroscience↗

Encoding of wind direction by central neurons in Drosophila

Wind is a major navigational cue for insects, but how wind direction is decoded by central neurons in the insect brain is unknown. Here, we find that walking flies combine signals from both antennae to orient to wind during olfactory search behavior. Movements of single antennae are ambiguous with respect to wind direction, but the difference between left and right antennal displacements yields a linear code for wind direction in azimuth. Second-order mechanosensory neurons share the ambiguous responses of single antenna and receive input primarily from the ipsilateral antenna. Finally, we identify a novel set of neurons, which we call wedge projection neurons, that integrate signals across the two antennae and receive input from at least three classes of second-order neurons to produce a more linear representation of wind direction. This study establishes how a feature of the sensory environment - the wind direction - is decoded by single neurons that compare information across two sensors.

neuroscience↗