219 | A chemogenetic approach to understand the role of the piriform cortex in an olfactory-contextual associative learning task

Neural Circuits and Systems Neuroscience

Author: Lucca Salomon | Email: luccasalomon@gmail.com

Lucca Salomon , Noel Federman , Sebastián A. Romano , Julieta Campi , Antonia Marin-Burgin

1° Biomedicine Research Institute of Buenos Aires (IBioBA) – CONICET – Partner Institute of the Max Planck Society

In the last ten years, new findings changed the way we think about sensory representations in the cerebral cortex, showing that their nature is plastic and can be modified by experience. In particular, a unique feature of olfactory processing is its high dependence on past experience, context, and the animal’s internal state.

To deepen the understanding of the modulation of sensory learning, we developed an olfactory-contextual conditioning paradigm in a virtual reality environment in which mice learn to associate an odor with a water reward when presented in a specific visual context.

Here we studied the piriform cortex (PCx), the largest region of the olfactory cortex, by performing in-vivo electrophysiological recordings while animals behave in the task, and started to address the importance of this brain region by bilaterally silencing its excitatory neurons using chemogenetics.

Interestingly, preliminary results show that silencing PCx impaired the animal’s performance. What is more, the ability to distinguish odors was more affected than the one to discriminate visual contexts. These results suggest that the piriform cortex plays an important role in the studied task and that it may be linked to both olfactory and associative functions.