Neural Encoding of Odors during Active Sampling and in Turbulent Plumes
Abstract
Sensory inputs are often fluctuating and intermittent, yet animals reliably utilize them to direct behavior. Here we ask how natural stimulus fluctuations influence the dynamic neural encoding of odors. Using the locust olfactory system, we isolated two main causes of odor intermittency: chaotic odor plumes and active sampling behaviors. Despite their irregularity, chaotic odor plumes still drove dynamic neural response features including the synchronization, temporal patterning, and short-term plasticity of spiking in projection neurons, enabling classifier-based stimulus identification and activating downstream decoders (Kenyon cells). Locusts can also impose odor intermittency through active sampling movements with their unrestrained antennae. Odors triggered immediate, spatially targeted antennal scanning that, paradoxically, weakened individual neural responses. However, these frequent but weaker responses were highly informative about stimulus location. Thus, not only are odor-elicited dynamic neural responses compatible with natural stimulus fluctuations and important for stimulus identification, but locusts actively increase intermittency, possibly to improve stimulus localization.
Additional Information
© 2015 Elsevier Inc. Received: December 3, 2014; Revised: May 11, 2015; Accepted: August 31, 2015; Published: October 8, 2015. This work was supported by the NIH and the Max Planck Society (G.L.), by grants from the U.S. Office of Naval Research (G.L. and S.C.), and by an intramural NIH-NICHD grant (M.S.). We thank Kristin Branson for advice on the automated antennal tracking and the Laurent Lab and Simon Laughlin for discussion and comments. Author Contributions: M.S., S.J.H., S.C., and G.L. conceived the experiments and wrote the manuscript. M.S. performed the odor plume experiments, and M.S. and Z.N.A. analyzed them. S.J.H. performed the active sampling behavior experiments. S.J.H. and S.C. performed the active sampling electrophysiology experiments, and S.J.H. analyzed the resulting data. G.L. managed and supervised the work.Attached Files
Accepted Version - nihms722571.pdf
Supplemental Material - mmc1.pdf
Supplemental Material - mmc2.mp4
Files
Additional details
- PMCID
- PMC4742573
- Eprint ID
- 61241
- Resolver ID
- CaltechAUTHORS:20151019-085059784
- NIH
- Max Planck Society
- Office of Naval Research (ONR)
- National Institute of Child Health and Human Development (NICHD)
- Created
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2015-10-19Created from EPrint's datestamp field
- Updated
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2022-05-19Created from EPrint's last_modified field