Séminaire de Julien Corbo

Lundi 30 juin 2025, à 14:00, Salle Laurent Vinay, INT

Julien Corbo (Rutgers University Newark)

Experience-Driven Restructuring of Sensory Representations in the Visual Cortex

Abstract: How does experience reshape early sensory representations to support perceptual decisions? In this talk, I will present work showing how training for a perceptual task transforms population activity in the primary visual cortex (V1) of mice, with a focus on feature representation. Using two-photon calcium imaging in layer 2/3, we recorded V1 activity while animals performed a Go/NoGo task with oriented drifting gratings. By comparing trained and naïve animals, we found that learning induces surround suppression in the orientation encoding space around the task-relevant values. This reorganization enhances the contrast between task cues and neighboring orientations, promoting both sharpened responses to the trained stimuli and generalization within their vicinity. In parallel, this modulation discretizes population activity into distinct orientation domains aligned with the behavioral categories. The integrated activity within these domains reliably predicts discrimination ability for different pairs of stimuli, reconciling neurometric and psychometric performances. I will also briefly outline ongoing work aimed at uncovering the time course of these learning-induced changes, their relationship to task performance, and their implications for downstream readout during perceptual decisions.