Fig. 8. Learning starts with a general suppression phase followed by a specific enhancement phase.

a A schematic illustration of the main cortical changes with regard to the two temporal scales: trial (x-axis) and learning (y-axis). Two phases occur across learning: before mice actually learn to discriminate between textures, association areas display non-specific suppression of activity in response to the cue (phase 1: non-specific suppression). Only later, as mice learn the task, a specific sequential pattern is enhanced: starting from A1 in response to the cue, then RL just before the texture touches the whiskers, and BC during texture touch (phase 2: specific enhancement). Association areas PM and RD specifically remain suppressed. b Schematic diagram showing the distribution of activity across association areas during the pre-period (i.e. in preparation of the upcoming texture touch) for the naïve (gray), pre-learning (dashed gray), and expert (black) phase.