Loss of Arc renders the visual cortex impervious to the effects of sensory experience or deprivation

A myriad of mechanisms are suggested to account for the full richness of visual cortical plasticity. We report that visual cortex lacking Arc is impervious to the effects of deprivation or experience. Using intrinsic signal imaging and chronic visually evoked potential recordings, we find that Arc(−/−) mice do not exhibit depression of deprived eye responses or a shift in ocular dominance after brief monocular deprivation. Extended deprivation also fails to elicit a shift in ocular dominance or open eye potentiation. Moreover, Arc(−/−) mice lack stimulus–selective response potentiation. Although Arc(−/−) mice exhibit normal visual acuity, baseline ocular dominance is abnormal and resembles that observed after dark–rearing. These data suggest that Arc is required for the experience–dependent processes that normally establish and modify synaptic connections in visual cortex.