" THE ADULT BRAIN, it turns out, is not just plastic but, as James Olds, a professor of neuroscience who directs the Krasnow Institute for Advanced Study at George Mason University, puts it, “very plastic.”16 Or, as Merzenich himself says, “massively plastic.”17 The plasticity diminishes as we get older—brains do get stuck in their ways—but it never goes away. Our neurons are always breaking old connections and forming new ones, and brand-new nerve cells are always being created. "

― Nicholas Carr , The Shallows: What the Internet Is Doing to Our Brains