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Title: The functional logic of odor information processing in the Drosophila antennal lobe
Recent advances in molecular transduction of odorants in the Olfactory Sensory Neurons (OSNs) of theDrosophilaAntenna have shown that theodorant object identityis multiplicatively coupled with theodorant concentration waveform. The resulting combinatorial neural code is a confounding representation of odorant semantic information (identity) and syntactic information (concentration). To distill the functional logic of odor information processing in the Antennal Lobe (AL) a number of challenges need to be addressed including 1) how is the odorantsemantic informationdecoupled from thesyntactic informationat the level of the AL, 2) how are these two information streams processed by the diverse AL Local Neurons (LNs) and 3) what is the end-to-end functional logic of the AL? By analyzing single-channel physiology recordings at the output of the AL, we found that the Projection Neuron responses can be decomposed into aconcentration-invariantcomponent, and two transient components boosting the positive/negative concentration contrast that indicate onset/offset timing information of the odorant object. We hypothesized that the concentration-invariant component, in the multi-channel context, is the recovered odorant identity vector presented between onset/offset timing events. We developed a model of LN pathways in the Antennal Lobe termed the differential Divisive Normalization Processors (DNPs), which robustly extract thesemantics(the identity of the odorant object) and the ON/OFF semantic timing events indicating the presence/absence of an odorant object. For real-time processing with spiking PN models, we showed that the phase-space of the biological spike generator of the PN offers an intuit perspective for the representation of recovered odorant semantics and examined the dynamics induced by the odorant semantic timing events. Finally, we provided theoretical and computational evidence for the functional logic of the AL as a robustON-OFF odorant object identity recovery processoracross odorant identities, concentration amplitudes and waveform profiles.  more » « less
Award ID(s):
2024607
PAR ID:
10483131
Author(s) / Creator(s):
; ;
Editor(s):
Morozov, Alexandre V.
Publisher / Repository:
PLOS
Date Published:
Journal Name:
PLOS Computational Biology
Volume:
19
Issue:
4
ISSN:
1553-7358
Page Range / eLocation ID:
e1011043
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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