This is part of IEEE Spectrum's SPECIAL REPORT: WINNERS & LOSERS 2009, The Year's Best and Worst of Technology.

PHOTO: Emotiv Systems

Controlling objects with just your thoughts has been a dream of sci-fi from ”Star Trek” to Star Wars , but in the past few years that dream has inched closer to reality. Brain-computer interfaces have allowed wheelchair-bound quadriplegics to move cursors on screens and monkeys to control robot arms.

Now a San Francisco–based company called Emotiv Systems is trying to bring the technology to PC game applications. It had planned to release its Epoc headset, a plastic frame dotted with 16 electrodes, in time for Christmas, but now the company says only that it’ll put the thing on sale ”soon,” for about US $300.

How the Epoc works isn’t entirely clear. The company says that it relies exclusively on brain waves, but independent observers say that it might instead be picking up other sorts of signals. In either case, the headset couldn’t let you manipulate fast-moving characters in Grand Theft Auto just by thinking about it.

Such a hair-trigger response would require some pretty significant breakthroughs in electroencephalography (EEG). Researchers have been using this form of brain-wave monitoring since the 1920s, largely because it is simple and cheap to operate. Still, scalp EEG sensors like Emotiv’s are far less accurate than experimental setups that insert electrodes into the brain through holes drilled in the skull, as was done with the monkeys who were taught to control robot arms.

Worse, EEG signals are weak, noisy, and slow. ”Video gamers spend lots of money buying fast computers and fast graphics cards,” says IEEE Fellow Kenneth Foster, a bioengineering professor at the University of Pennsylvania who has long studied the medical applications of EEG. ”Why would they then hook themselves up to a computer that allows them to do the equivalent of typing one or two words a minute with a 50 percent error rate?”

The mainstream media has hyped the technology with breathless headlines like ”Next-Gen Vidgame Gear Reads Minds” ( Variety ) and ”Control GTA With the Power of Your Mind” (T3.com). But that’s not how brain-computer interfaces work.

”It’s not that someone’s thinking about doing something and the computer records the person’s thoughts,” said Foster. ”It’s just that through a training sequence, you can be taught how to fire those neurons near where the electrode is.”

Expert Call: ”On the brain-machine interface, I’m not sure I trust either the technology or my brain.”
–Robert W. Lucky, IEEE Fellow; former vice president, applied research, TelcordiaTechnologies

Think of it this way: learning to steer a cursor with EEG is like learning to wiggle your ears—it’s not done well, but it’s amazing that it is done at all.