Repeated passive visual experience modulates spontaneous and novelty-evoked neural activity.

Familiarity creates subjective memory of repeated passive innocuous experiences, reduces neural and behavioral responsiveness to those experiences, and enhances novelty detection. The neural correlates of the internal model of familiarity and the cellular mechanisms of enhanced novelty detection following multi-day repeated passive experience remain to be better understood. Using the mouse visual cortex as a model system, we test how the repeated passive experience of an orientation-grating stimulus for multiple days alters spontaneous, and non-familiar stimuli evoked neural activity in neurons tuned to familiar or non-familiar stimuli. We found that familiarity elicits stimulus competition such that stimulus selectivity reduces in neurons tuned to the familiar stimulus, whereas it increases in those tuned to non-familiar stimuli. Consistently, neurons tuned to non-familiar stimuli dominate local functional connectivity. Furthermore, responsiveness to natural images, which consists of familiar and non-familiar orientations, increases subtly in neurons that exhibit stimulus competition. We also show the similarity between familiar grating stimulus-evoked and spontaneous activity increases, indicative of an internal model of altered experience.