Visual experience drives functional reorganization of cortical GABAergic circuits

Sensory deprivation leads to extensive cortical plasticity, but the impact of enhanced sensory experience on the mature cortex remains poorly understood. Here, we examine how visually evoked activity in cortical circuits is shaped by repeated exposure to varied stimuli. The most prominent pattern of visually evoked activity in mouse primary visual cortex, beta oscillations (15-30Hz), arises from brief events of neural synchrony with a characteristic pattern of laminar propagation and relies on the activity of somatostatin-expressing (SST) GABAergic interneurons. We find that visually evoked beta activity is initially weak but robustly potentiated by repeated exposure to a diverse visual stimulus set, leading to enhanced recruitment of cortical neurons by these rhythmic network events. Cellular imaging further reveals that visual experience leads to increased visual responses in SST interneurons and suppressed responses in vasoactive intestinal peptide-expressing (VIP) GABAergic interneurons. In association with this rebalancing of inhibitory circuits, visual experience enhances visual selectivity in nearby pyramidal neurons. Visual experience thus selectively reorganizes adult dendrite-targeting inhibitory circuits, promoting network synchrony and enhancing sensory encoding by cortical excitatory projection neurons.