Neural Circuits and Systems Neuroscience
Author: Lucca Salomon | Email: lsalomon@ibioba-mpsp-conicet.gov.ar
Lucca Salomon1°2°, Noel Federman1°, Julieta Campi1°, Sebastián Alejo Romano1°, Antonia Marin-Burgin1°
1° Biomedicine Research Institute of Buenos Aires (IBioBA) – CONICET – Partner Institute of the Max Planck Society.
2° University of Buenos Aires, Faculty of Exact and Natural Sciences, PhD Program, Buenos Aires, Argentina.
Recent discoveries have transformed our understanding of sensory representations in the cerebral cortex, revealing their plasticity and sensitivity to experience. Olfactory processing, in particular, depends on prior experiences, context, and the animal’s internal state.
To investigate how sensory learning dynamically changes responses in cortical circuits, we created an olfactory-contextual conditioning paradigm within a virtual reality setting. In this setup, mice are trained to associate a specific odor with a water reward when presented in a particular visual context. We focused on the piriform cortex (PCx), the largest area of the olfactory cortex, and conducted in-vivo electrophysiological recordings while the animals engaged in the task.
We found that several behavioral variables (licking, locomotion, sniffing) modulate the PCx neuronal activity, and by comparing naive, intermediate and expert session animals, we observed that the response to non-olfactory variables, including contextual modulation, were sequentially acquired during learning. In particular, while expert animals encode contextual information in the PCx, those that learn to discriminate odors but not yet contexts (intermediate session) do not. This study highlights the sequential acquisition of contextual encoding in the PCx and provides insights into how sensory learning reshapes cortical representations. Future experiments will focus on the mechanism by which contextual information arises in the PCx.