For decades scientists have been searching for a way to watch a live broadcast of the brain. Neurons send and receive massive amounts of information — toe itches! Fire hot! Garbage smells! — at speeds up to 270 miles per hour. Now, with a new microscope, noise-cutting software, red and blue light, and a homemade projector, researchers can capture something no one has seen before: neurons flashing in real time, in a walking, living creature.