XII congress, International society for Neuroethology, Montevideo, Uruguay

Very interesitng conference in Montevideo about Neuroethology. We went there presenting our results on moths and honeybees....

here the abstracts:

APPETITIVE AND AVERSIVE PHEROMONES INDUCE OPPOSED MODULATIONS OF APPETITIVE SUCROSE RESPONSIVENESS AND LEARNING AND MEMORY PERFORMANCES IN HONEY BEES David Baracchi; Jean-Marc Devaud; Patrizia D'Ettorre; Martin Giurfa

Pheromones are chemical messengers eliciting stereotyped behavioural and/or physiological responses in receivers. Besides their well-documented function as communication signals, pheromones have been recently shown to act as “modulators” of cognitive phenomena, facilitating or inhibiting associative learning and memory. We used Apis mellifera to study the effect of exposure to one appetitive pheromone (geraniol) and two alarm pheromones (IPA and 2-heptanone) on sucrose responsiveness, appetitive learning and memory performances. Sucrose responsiveness was measured via the proboscis extension response (PER) to increasing concentrations of sucrose solution. Learning and memory via the olfactory PER differential conditioning (one odour is paired with sucrose and the other remains non-rewarded). We found that alarm pheromones induced a significant decrease of sucrose responsiveness so that 40% and 60% of bees exposed to IPA and 2-hepanone respectively, did not respond to any sucrose concentration. In bees that responded to sucrose, geraniol and 2-heptanone induced an increase and a decrease of the bees’ sucrose responsiveness respectively, while IPA had no effect. Bees exposed to geraniol not only improved their learning performance, but had also better memory retention up to 24 hours than control bees exposed to mineral oil. By contrast, 2-heptanone strongly inhibited appetitive learning and memory retention up to three days following conditioning with respect to controls. Contrary to our expectations and previous results, IPA did neither modulate appetitive learning nor memory performance. Overall, these results suggest that pheromones provide contextual information that makes subsequent learning and memory more or less relevant for the context signalled by conspecifics.

PHEROMONES AS MODULATORS OF INSECT BEHAVIOR Nina Deisig Pheromones are conspecific communication signals usually eliciting stereotyped behavioural or physiological responses. They trigger immediate or delayed innate responses to relevant stimuli, and thus are crucial for regulating social or sexual interactions. However, pheromones have also been suggested to act as “modulators” of cognitive phenomena, facilitating or inhibiting associative learning and memory. We study the modulator effect of pheromones on experience-dependent insect behaviour in order to determine mechanisms that are either conserved across species or species-specific and associable with particular life-styles. To this end, we use a combination of behavioural, pharmacological and physiological (optical imaging) methods in bees, ants and moths.