Integration of the whole network. Crowds simultaneously logging onto a single website can slow or crash the system. Neurologists believe the same sort of jam-up happens when something affects a part of the brain, be it a migraine or a devastating tumor. To better understand how the brain's wiring is interconnected, an international consortium of researchers is now creating a comprehensive diagram of the entire circuitry: the major highways leading to the smaller roads, down to each individual driveway or single neuron, says Olaf Sporns, professor of psychological and brain sciences at Indiana University. Using diffusion MRI on a handful of people, Sporns's team has already begun getting a sense of the routes within the cerebral cortex. The goal of this Human Connectome Project is to gather the wisdom that will come from imaging some 1,200 brains.