Sensory and Motor Systems
Author: Marcos Rafael Sorrentino | Email: marcosrafa.sorrentino@gmail.com
Marcos Rafael Sorrentino1°, Agustín Lara1°2°,Nicolás Pírez1°2°, Fernando Locatelli1°2°
1° Departamento de Fisiología, Biología Molecular y Celular; Facultad de Ciencias Exactas y Naturales; Universidad de Buenos Aires, Argentina.
2° Instituto de Fisiología, Biología Molecular y Neurociencias; UBA-CONICET, Argentina.
We investigate the mechanisms by which the perception of a stimulus is influenced by an immediately preceding stimulus. Specifically, we focus on how exposure to one odor affects the perceptual quality of an odor presented immediately afterward. We propose two hypotheses: 1) Exposure to an odor triggers a sensory adaptation period that affects the perception of a second odor that takes place during this period and 2) Exposure to two consecutive odors is associated by the animal in such a way that the entire sequence of odors is perceived as a single stimulus. We use bees and classical conditioning of the proboscis extension to test these hypotheses. First, we examine learning with a binary odor mixture and the extent to which learning generalizes to the components of the mixture. We observed that if bees are exposed to one of the components of the mixture immediately before the conditioning trial, learning of the exposed component is reduced while learning of the non-exposed component increases. This phenomenon does not occur if the exposure to the component happens after the conditioning trial, indicating a sensory adaptation effect on the perception of the mixture. In the second experiment, we investigate whether bees can discriminate between two inverted sequences of odors where one predicts an appetitive reward and the other an aversive stimulus. The results so far indicate that bees more easily learn the last odor in the sequence that is temporally closer to the reward.