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Updated: May 26, 2026
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Calcium Imaging of Odor-evoked Responses in the Drosophila Antennal Lobe
Published on: March 14, 2012
Excitatory local circuits and their implications for olfactory processing in the fly antennal lobe
Yuhua Shang1, Adam Claridge-Chang, Lucas Sjulson
1Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
Cell
|February 10, 2007
Summary
Insect olfactory circuits use local neurons to broaden odorant responses. New research reveals cholinergic local neurons (LNs) excite projection neurons (PNs), enhancing olfactory signal transmission.
Area of Science:
- Neuroscience
- Olfactory system research
- Insect neurobiology
Background:
- The antennal lobe, insect olfactory bulb equivalent, translates olfactory receptor neuron (ORN) input to projection neuron (PN) output.
- A discrepancy exists between one-to-one ORN-PN synapses and broader PN odorant tuning.
Purpose of the Study:
- Investigate the basis for broader PN odorant tuning compared to ORN input.
- Identify mechanisms contributing to antennal lobe circuit output complexity.
Main Methods:
- Analysis of a Drosophila mutant lacking ORN input to a specific glomerulus.
- Characterization of local neuron (LN) populations and their connectivity.
Main Results:
- Identified a novel population of cholinergic local neurons (LNs) with multiglomerular processes.
- Demonstrated that these LNs provide diffuse, excitatory input to PNs.
- Showed that lateral, interglomerular excitation of PNs contributes to antennal lobe output complexity.
Conclusions:
- PNs receive both glomerulus-specific ORN input and diffuse LN excitation.
- Lateral excitation by LNs may enhance PN signal transmission, potentially via stochastic resonance.
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