For the last four years, Henry Markram has been building a biologically accurate artificial brain. Powered by a supercomputer, his software model closely mimics the activity of a vital section of a rat's gray matter.

Dubbed Blue Brain, the simulation shows some strange behavior. The artificial "cells" respond to stimuli and suddenly pulse and flash in spooky unison, a pattern that isn't programmed but emerges spontaneously.

"It's...