Present address : Rockefeller University, New York, USA.
The coding of odour-intensity in the honeybee antennal lobe: local computation optimizes odour representation
Version of Record online: 22 OCT 2003
European Journal of Neuroscience
Volume 18, Issue 8, pages 2119–2132, October 2003
How to Cite
Sachse, S. and Galizia, C. G. (2003), The coding of odour-intensity in the honeybee antennal lobe: local computation optimizes odour representation. European Journal of Neuroscience, 18: 2119–2132. doi: 10.1046/j.1460-9568.2003.02931.x
- Issue online: 22 OCT 2003
- Version of Record online: 22 OCT 2003
- Received 13 November 2002, revised 19 July 2003, accepted 29 July 2003
- Apis mellifera;
- calcium-sensitive dye;
- odour processing;
- olfactory projection neurons;
- optical recording
We investigated strategies involved in odour intensity coding by the primary olfactory centre of insects, the antennal lobe (AL), the structural and functional analogue of the olfactory bulb. Using calcium imaging in the honeybee, we simultaneously measured the projection neuron output responses and a compound signal dominated by receptor neuron input in identified olfactory glomeruli to odours spanning seven log units of concentration. A comparison of the two processing levels indicates that the intercellular computation within the AL modulates and contrast-enhances the primary olfactory signals. As a result the AL network optimizes the olfactory code: odour representation is improved at lower concentrations, the relative activity of olfactory glomeruli allows encoding odour quality over up to four log-unit concentrations, and odour-intensity is reliably represented in the overall excitation across AL.