Olfactory receptor neurons use gain control and complementary kinetics to encode intermittent odorant stimuli
Abstract
Insects find food and mates by navigating odorant plumes that can be highly intermittent, with intensities and durations that vary rapidly over orders of magnitude. Much is known about olfactory responses to pulses and steps, but it remains unclear how olfactory receptor neurons (ORNs) detect the intensity and timing of natural stimuli, where the absence of scale in the signal makes detection a formidable olfactory task. By stimulating Drosophila ORNs in vivo with naturalistic and Gaussian stimuli, we show that ORNs adapt to stimulus mean and variance, and that adaptation and saturation contribute to naturalistic sensing. Mean-dependent gain control followed the Weber-Fechner relation and occurred primarily at odor transduction, while variance-dependent gain control occurred at both transduction and spiking. Transduction and spike generation possessed complementary kinetic properties, that together preserved the timing of odorant encounters in ORN spiking, regardless of intensity. Such scale-invariance could be critical during odor plume navigation.
Article and author information
Author details
Funding
Whitehall Foundation
- Srinivas Gorur-Shandilya
- Mahmut Demir
- Thierry Emonet
Sloan Research Fellowship
- Damon A Clark
Searle Scholar Award
- Damon A Clark
Smith Family Foundation
- Damon A Clark
Natural Sciences and Engineering Research Council of Canada (PGSD2-471587-2015)
- Junjiajia Long
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Gorur-Shandilya 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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