Systematic Microcircuit Reconfigurations Underlie Early Experience-induced Visual Cortical Plasticity

Experience-dependent reorganization of neuronal connections during the postnatal critical period is essential for the functional maturation of the developing primary visual cortex (V1). However, the systematic reconfigurations across microcircuit synapses underlying experience-dependent plasticity are poorly defined. Using paired whole-cell recordings from excitatory pyramidal cells and three other major classes of interneurons (INs) within layers 2/3 and 4 in the developing mouse V1 monocular region, we found that monocular deprivation (MD) for one day in juvenile mice transiently reconfigures local excitatory synapses onto inhibitory INs that specifically express parvalbumin (PV) or vasoactive intestinal peptide (VIP). In contrast, prolonged MD predominantly strengthens inhibitory synaptic transmission from somatostatin (SST)-expressing INs to PV-INs and VIP-INs across both layers. A physiologically based microcircuit model further recapitulated MD-induced activity changes in visual responses across layer 2/3 neurons in vivo. We provide a detailed microcircuit framework that contributes to the experience-dependent regulation of visual function.