Sensory adaptation and the representation of complex odors in the antennal lobe of Apis mellifera

GASCUE, F.; PÍREZ, N.; LOCATELLI, F

Buenos Aires

Congreso; XXXV REUNIÓN ANUAL SAN 2020 VIRTUAL; 2020

Sociedad Argentina de Investigación en Neurociencias

Sensory systems must be adjusted based on the animal?s experience in order to optimize perception of relevant information and ignore stimuli without predictive value. In this context, one of the main phenomena that modulate the olfactory system is adaptation, which is defined as the decrease of the sensitivity or response to an odor after a sustained exposure to it. Adaptation may occur in brief intervals of time and depends on the immediate experience of the animal. In this project, we use Apis mellifera to study the representation of binary mixtures of odors in the brain after sensory adaptation to one of the components. We performed calcium imaging experiments to measure odor induced signals in the antennal lobe, the first olfactory neuropil in the insect brain. We determined that, after olfactory adaptation, response patterns encoding the mixture are drastically altered, in a way that favors the representation of the non-adapted component. These changes are relatively brief, lasting about a minute. Additionally, by means of behavioral experiments, we show that adaptation reduces appetitive learning of the adapted component, while it enhances learning of the other component in cases in which it would normally stay occluded. These results suggest that olfactory adaptation is critical to allow detection of minor components present in complex mixtures, emphasizing that sensory adaptation is a fundamental mechanism to improve sensitivity to salient and discrete stimuli.