Very brief visual experience eliminates plasticity in the cat visual cortex.

Rearing cats in the dark extends the critical period for development of visual cortical neurons, which indicates that the experience of visual input is necessary to begin the developmental process. A single brief pulse of visual input (6 hours) during a period of dark-rearing eliminates delayed development in the visual cortex. Light therefore seems to rapidly trigger the developmental process, and once triggered, that process runs to completion in the absence of further input.