By Will Dunham WASHINGTON (Reuters) -Neuroscientists have produced the largest wiring diagram and functional map of a mammalian brain to date using tissue from a part of a mouse's cerebral cortex involved in vision,

Thanks to a mouse watching clips from "The Matrix," scientists have created the largest functional map of a brain to date - a diagram of the wiring connecting 84,000 neurons as they fire off messages.

In all, they collected data that covers about 3.4 miles (5.4 kilometers) of neuronal wiring in a part of the brain that processes visual information from the eyes.