Neural circuit mechanisms for transforming learned olfactory valences into wind-oriented movement
Abstract
How memories are used by the brain to guide future action is poorly understood. In olfactory associative learning in Drosophila, multiple compartments of the mushroom body act in parallel to assign a valence to a stimulus. Here, we show that appetitive memories stored in different compartments induce different levels of upwind locomotion. Using a photoactivation screen of a new collection of split-GAL4 drivers and EM connectomics, we identified a cluster of neurons postsynaptic to the mushroom body output neurons (MBONs) that can trigger robust upwind steering. These UpWind Neurons (UpWiNs) integrate inhibitory and excitatory synaptic inputs from MBONs of appetitive and aversive memory compartments, respectively. After formation of appetitive memory, UpWiNs acquire enhanced response to reward-predicting odors as the response of the inhibitory presynaptic MBON undergoes depression. Blocking UpWiNs impaired appetitive memory and reduced upwind locomotion during retrieval. Photoactivation of UpWiNs also increased the chance of returning to a location where activation was terminated, suggesting an additional role in olfactory navigation. Thus, our results provide insight into how learned abstract valences are gradually transformed into concrete memory-driven actions through divergent and convergent networks, a neuronal architecture that is commonly found in the vertebrate and invertebrate brains.
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numerical data used to generate the figures in this study uploaded as source data.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Yoshinori Aso
National Institutes of Health (R01DC018874)
- Toshihide Hige
National Science Foundation (2034783)
- Toshihide Hige
U.S-Israel Binational Science Foundation (2019026)
- Toshihide Hige
UNC Junior Faculty Development Award
- Toshihide Hige
Japan Society for the Promotion of Science (Overseas Research Fellowship)
- Daichi Yamada
Toyobo Biotechnology Foundation (Postdoctoral Fellowship)
- Daichi Yamada
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Ilona C Grunwald Kadow, University of Bonn, Germany
Version history
- Preprint posted: December 22, 2022 (view preprint)
- Received: December 22, 2022
- Accepted: September 7, 2023
- Accepted Manuscript published: September 18, 2023 (version 1)
- Version of Record published: October 20, 2023 (version 2)
- Version of Record updated: October 27, 2023 (version 3)
Copyright
© 2023, Aso et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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