In search for intelligence, a silicon brain twitches

By Gautam Naik - The Wall Street Journal
14 Jul, 2009

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 the neuronal equivalent of a Mexican wave," says Dr. Markram, referring to what happens when successive clusters of stadium spectators briefly stand and raise their arms, creating a ripple effect. Such synchronized behavior is common in flesh-and-blood brains, where it's believed to be a basic step necessary for decision making. But when it arises in an artificial system, it's more surprising.

Blue Brain is based at the École Polytechnique Fédérale de Lausanne in Switzerland. The project hopes to tackle one of the most perplexing mysteries of neuroscience: How does human intelligence emerge? The Blue Brain scientists hope their computer model can shed light on the puzzle, and possibly even replicate intelligence in some way.

"We're building the brain from the bottom up, but in silicon," says Dr. Markram, the leader of Blue Brain, which is powered by a supercomputer provided by International Business Machines Corp. "We want to understand how the brain learns, how it perceives things, how intelligence emerges."

Blue Brain is controversial, and its success is far from assured. Christof Koch of the California Institute of Technology, a scientist who studies consciousness, says the Swiss project provides vital data about how part of the brain works. But he says that Dr. Markram's approach is still missing algorithms, the biological programming that yields higher-level functions.

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