Neurobiologist Carla Shatz poses the question of whether we will one day soon be able to make an old brain young? In exploring the question, she shares her groundbreaking research on how brain circuits are “tuned up” during critical periods of development, and how our visual system is inextricably tied to brain plasticity. These are some of the findings that she hopes will eventually inform the creation of a pill to rewire our brains to operate as they did when we were young.