Sensory adaptation and dynamic odor representations on the honey bee antennal lobes

FERNANDO LOCATELLI; NICOLAS PIREZ; FEDERICO GASCUE

Helsinki

Congreso; International Conference for Entomology; 2022

ICE Helsinki 2022 invited TALK presented at symposium: “Experience-dependentplasticity in insect sensory circuits”. Sensory adaptation and dynamic odor representations onthe honey bee antennal lobesLocatelli Fernando, Nicolás Pírez y Federico Gascue. Institute for Physiology, Cellular and MolecularBiology, University of Buenos Aires, CONICET. Argentina.Animals processand perceive environmental information in flexible ways. Some changes inperception are sustained and involve learning and memory processes while othersoccur quickly and are only transient. In this framework, sensory adaptation isdefined as the phenomenon by which the sensitivity to a stimulus decreasesafter a sustained exposure to it. This phenomenon is characterized by a rapidloss of sensitivity and full recovery within few seconds after the stimulusdisappears. Curiously, this phenomenon has been mostly studied by focusing on whatthe animal fails to perceive, but not on the consequences that it has on theperception of the stimuli for which the animal has not experienced adaptation.In this project we study the enriching effect that sensory adaptation has onthe ability of animals to detect stimuli to which it has not been adapted and thatwould remain overshadowed by dominant stimuli under normal conditions. We use honeybees Apis mellífera that have a highcapacity to learn and recognize odors. We perform behavior experiments to showthat this phenomenon reduces appetitive learning of adapted stimuli while itfavors learning of minor components that would normally stay occluded. Westudied this phenomenon at the level of sensory and projection neurons of theolfactory system. We determine that antennal lobe activation patterns thatencode mixtures in the antennal lobe are drastically altered after sensoryadaptation, in a way that favors the representation of stimuli that are presentat sub-threshold concentrations. The results obtained so far emphasize thatsensory adaptation is a fundamental mechanism to increase the sensitivity ofthe animal and not to reduce it.