Playing With Your Head: The Dawning Age of Mind-Reading Machines
Imagine controlling machines, typing text or juggling balls using nothing but the power of thought. What sounds like far-fetched science fiction is gradually becoming possible, providing hope for disabled patients -- and new gimmicks for the computer gaming industry.
DIZ SENTENS IS WRUTEN WID TAUGHTS. No keyboard, no hands, no blinking even. I think, therefore I write.
My original plan was to write this article with nothing but the power of thought, but the technology of transforming ideas into characters is still crude and prone to error. The first word alone took a few minutes, and even after that the result was still "diz" instead of "this."
Still, that little sentence is like a little miracle. The old dream of mind-reading is slowly becoming reality -- though this time around it is the product of machines rather than the minds of fiction writers.
"The advances are tremendous," says Christoph Guger, the developer of a brain-reading system. "In the past, you would have had to train for days. Today, entering text takes only a few minutes."
Guger is an engineer and a businessman. But with his hair falling past his jacket's collar, he looks the part of a start-up entrepreneur. Still, he is certainly not new to the business. His company, Guger Technologies, which is based in the Austrian city of Graz, has been a supplier to countless brain-research laboratories for years. In addition to scalpels and medications, though, Guger also sells thought-transport technology.
Guger recently presented his latest thought-reading system at a workshop entitled "Brain-Computer Interfaces" held at Berlin's Charité, one of Europe's largest university hospitals. The new electronic interfaces between brain and computer are referred to as BCI.
Hardware and Wetware
The goal of BCI is to enable the user to use thoughts -- instead of a keyboard, mouse or touch screen -- to control a computer's actions. But what sounds like telepathy is, in fact, quite banal. First the user puts on a device that looks like a bathing cap. Then an electrically conductive gel is squeezed through small holes in the cap onto the scalp. Finally, eight electrodes are plugged into the cap, and a colorful array of dreadlock-resembling cables are attached to the electrodes. The cables are then connected to the computer through a signal amplifying interface. So much for the hardware.
Then the "wetware" -- the term IT researchers sometimes use to refer to the brain -- takes over. An alphabet flickers across a screen in front of the subject, and the letters light up one at a time. The user waits until the letter he or she wants to use appears. When it lights up, the brain has an involuntary reaction that produces a small "electric potential," a tiny increase in voltage of about 15 microvolts, which is 100,000 times weaker than the voltage generated by a flashlight battery.
The principle is based on the tried-and-tested EEG, or electroencephalogram. The brain's small gray cells fire off electrical signals, which can be measured on the surface of the scalp. Guger's special method is called P300, a reference to the sudden fluctuation in voltage he is looking for, which appears in the visual cortex of the brain 300 milliseconds after each expected letter flashes on the screen.
This method is very rudimentary in the sense that it doesn't really read a thought but, rather, merely the average activity of millions of neurons. Likewise, those neurons may not be reacting only to letters, but also to someone else's sneeze or to tightness in the subject's left shoe. Guger's current task is to filter all of these interfering signals out of the chaotic flow of thoughts in the brain.
Brain Caps for Pinball
As challenging as this task might be, there was still a lot of excitement at the Berlin workshop. The project involves a rapidly growing group of researchers hoping to capture thoughts with what can best be described as an electronic camera. "Ten years ago, there were perhaps a dozen research groups in this field," says Klaus-Robert Müller, the director of the Machine Learning/Intelligent Data Analysis Group at the Technical University of Berlin. "Now there are more than 200."
Müller has also developed a BCI that works in a similar way to Guger's mental typewriter. His system isn't based on tediously poking around in a jumble of letters but, rather, on lightning-fast reactions. To develop the system, Müller has his subjects use their brain caps to play pinball.
When they think "right," the lever on the right side pops up. As if moved by the hand of a ghost, it flings the ball back into the game without anyone having touched the controls.
Müller is working closely with John-Dylan Haynes, one of the stars of the elite thought-reading community. Haynes attracted attention last year when he reported that, using a magnetic resonance imaging (MRI) machine, he had correctly guessed the decisions of his subjects before they were able to act in more than half of the cases. A full seven seconds before they moved a finger, Haynes could see that they were planning to press a specific button.
After Müller's presentation, Niels Birbaumer stood up to speak at the Berlin conference. Birbaumer is the director of the Institute of Medical Psychology and Behavioral Neurobiology at the University of Tübingen in southwestern Germany and is considered a pioneer in the field. For years, he has been trying to teach people with physical handicaps to control their wheelchairs or prosthetic limbs using only the power of thought. "Our successes are still modest," he says, "but I'm already totally crazy with hope." He expects that within two years he will be able to use his system with locked-in patients -- that is, paralyzed individuals who are fully aware of their surroundings but can move nothing other than their eyes -- for the first time within two years.
Communication with these types of patients is something of a Holy Grail in the profession because it promises to make it possible to help locked-in people like the lead character in the 2007 film "The Diving Bell and the Butterfly." In the film, an almost totally paralyzed patient dictates his memories to his therapist using the only means of communication he has left: blinking.
- Part 1: The Dawning Age of Mind-Reading Machines
- Part 2: Eavesdropping on Dreams
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