Monocular deprivation during the critical period alters neuronal tuning and the composition of visual circuitry
Abnormal visual experience during a developmental critical period degrades cortical responsiveness. Yet how experience-dependent plasticity alters the response properties of individual neurons and composition of visual circuitry is unclear. Here we measured with calcium imaging in alert mice how monocular deprivation (MD) during the developmental critical period affects binocularity, orientation, and spatial frequency tuning for neurons in primary visual cortex. Tracking the tuning properties for several hundred neurons revealed that the interconversion of monocular and binocular neurons relies on the quality of visual experience to determine the ratio of monocular neurons responsive to the contralateral and ipsilateral eye. In addition, a population of neurons more responsive to the closed eye were exchanged for neurons with tuning properties more similar to the responsive neurons altered by MD. Thus, plasticity during the critical period adapts to recent experience by both altering the tuning of responsive neurons and recruiting neurons with matching tuning properties.