Sensory adaptation and sharpening of odor detection in honey bees

LOCATELLI, F. F.; PÍREZ, N.; SORRENTINO, M.; GASCUE, F.

Buenos Aires

Congreso; VII Congress of the Latin American Meeting of Chemical Ecology; 2023

Asociación Latinoamerica de Ecología Quimica

Insects rely on their sense of smell to navigate complex environments and make decisions regarding food and reproduction. However, in natural conditions, the odors conveying this information often come mixed with concurrent environmental odors, which can obscure the perception of meaningful ones. Recognizing the presence of informative odors in this context involves intricate generalization and discrimination processes that can be adjusted based on experience and plasticity, both at the level of detection and central processing. Here we investigate the contribution of sensory adaptation to the detection of meaningful odors. Sensory adaptation is commonly defined as the phenomenon in which an animal´s sensitivity to a stimulus decreases after sustained exposure to it. This phenomenon is typically characterized by a rapid loss of sensitivity, followed by full recovery within a few seconds after the stimulus disappears. While previous research has predominantly focused on what the animal fails to perceive during sensory adaptation, little attention has been given to its consequences on the perception of other odors to which the animal has not been exposed. To address this, we used honeybees Apis mellifera, known for their high capacity to learn and recognize odors, as experimental subjects. We conducted behavioral experiments and observed that sensory adaptation not only reduces appetitive learning of adapted odors but also enhances learning of minor mixture components that would normally remain obscured. We examined this phenomenon at the level of sensory and projection neurons of the olfactory system. Our findings reveal that sensory adaptation significantly alters antennal lobe activation patterns, particularly in the representation of mixtures. This alteration appears to favor the representation of stimuli present at sub-threshold concentrations. In essence, our results emphasize that sensory adaptation serves as a fundamental mechanism to sharpen olfactory sensitivity of the animals.