In the early 1940s, Roger Sperry cut the optic nerve of a newt, rotated the detached eye 180 ° in its orbit, and assayed the visuomotor behavior of the animal after its nerve had regenerated. The newts, and in subsequent studies, frogs, behaved as if their visual world were back to front and upside down: when a lure was presented in front of them, =they wheeled rapidly to the rear instead of st...