Apprentissage olfactif associatif individuel chez la fourmi Camponotus mus

DUPUY, F; JOSENS, R; SANDOZ, JC.; GIURFA, M

Rennes, France

Congreso; Colloque annuel del’union internationale pour l’études des insectes sociaux; 2004

del’union internationale pour l’études des insectes sociaux

Our first objective was to determine, from behavioral observations, whether ants, taken individually, were able to display 1)discriminative olfactory capabilities and 2) olfactory associative learning. Our second objective was to test if it was possible to record neural activity from a specific population of neurons in the first relay of the olfactory system, the antennal lobe, using functional (calcium) imaging in vivo. In the behavioral experiments, Camponotus mus ants had to learn to choose between two odors, associated respectively with a positive (sugar) and a negative (quinine) reinforcement. Our results allow us to demonstrate that these ants are individually able to learn odorant stimuli. Calcium imaging experiments aimed to record olfactory responses to retrogradely-stained projection neurons, which carry information to brain superior centers after processing by the antennal lobe neuronal network. These experiments allowed us to obtain odor-induced calcium responses from these projection neurons in Camponotus fellah. These responses appear as local, odorant-specific, reproducible, activity variations restricted to small foci. From these results, we propose that odors are coded in a combinatory fashion by the projection neurons. In conclusion, we have developed new behavioral and neurobiological techniques in Camponotus ants, which will allow us to study learning and olfactory discrimination in these insects, which can become new invertebrate models for this kind of studies.