High order unimodal olfactory sensory preconditioning in Drosophila
Abstract
Learning and memory storage is a complex process that has proven challenging to tackle. It is likely that, in nature, the instructive value of reinforcing experiences is acquired rather than innate. The association between seemingly neutral stimuli increases the gamut of possibilities to create meaningful associations and the predictive power of moment-by-moment experiences. Here we report physiological and behavioral evidence of olfactory unimodal sensory preconditioning in fruit flies. We show that the presentation of a pair of odors (S1 and S2) before one of them (S1) is associated with electric shocks elicits a conditional response not only to the trained odor (S1) but to the odor previously paired with it (S2). This occurs even if the S2 odor was never presented in contiguity with the aversive stimulus. In addition, we show that inhibition of the small G protein Rac1, a known forgetting regulator, facilitates the association between S1/S2 odors. These results indicate that flies can infer value to olfactory stimuli based on the previous associative structure between odors, and that inhibition of Rac1 lengthens the time window of the olfactory 'sensory buffer', allowing the establishment of associations between odors presented in sequence.
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All data generated or analyzed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
National Institute of Mental Health (R21MH117485-01A1)
- Isaac Cervantes-Sandoval
Brain and Behavior Research Foundation (30442)
- Isaac Cervantes-Sandoval
National Institute on Aging (T32AG071745)
- Prachi Shah
Georgetown University (ID162838)
- Isaac Cervantes-Sandoval
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Martinez-Cervantes 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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