As everyone who buys a computer learns, electrical engineerssomehow manage to keep creating smaller and smaller microprocessors that double the speed of PCs about every 18 months. Keeping perspective can be difficult, but consider that the power of the first room-sized mainframe computer of 36 years ago is now dwarfed by any run-of-the-mill laptop. So what's wrong with this picture? Biomedical engineer William Ditto points out that today's processors may be a lot faster, but they're not a bit smarter than they were 40 years ago.
The dream of artificial intelligence that would allow a computer to learn, and thus get really smart, has proven to be something of a nightmare so far. That failure has led Ditto and his team of researchers at the Georgia Institute of Technology and Emory University to look beyond silicon and even beyond light chips. "First there were beads on an abacus, then vacuum tubes and integrated circuits," says Ditto. "Now we can use living tissue."
