Marco Della Torre sits in front of a huge flat screen, wearing a strange, spiderlike contraption on his head. He slowly raises his arms, and a virtual rock begins to glow and shake on-screen. It falters a little and then rises, hanging briefly in the air.
Della Torre, a product engineer at San Francisco startup Emotiv Systems, is demonstrating the company’s new game controller–a headset incorporating sensors that can detect brain activity. Emotiv and its competitor, San Jose-based Neurosky, are developing the first gaming devices to use electroencephalography (EEG), a decades-old technology in which electrodes placed on the scalp measure electrical activity in the brain.
In the hands of neurologists, EEG can be a powerful tool for, say, identifying the source of seizures in epilepsy patients. But game developers want to use EEG to let players control virtual environments with their minds. They hope EEG will become the next big computer interface–a step beyond devices like the Nintendo Wii remote, which allow players to convert their hand movements into actions on-screen.
Both Emotiv and Neurosky have generated huge buzz in the gaming world. But can the headsets really provide the experience gamers are looking for? “People tend to want to do science fiction and [use EEG signals to] aim the gun or fly the plane,” says Scott Makeig, a neuroscientist at the University of California, San Diego. “But actually, changes in EEG are tied to changes in alertness and arousal that are slow by their nature. To try to use it to do fast things is not very natural.”
And measuring brain signals is tricky enough in the first place. Slight muscle movements, for instance, can generate electrical potentials more than 10 times as strong as those produced by neurons. Scientists who use EEG try to filter out this noise through various means: improving sensor sensitivity by applying conductive gel to the scalp, arraying sensors in caps specially fitted to a subject’s head, and employing complex signal analysis. “It has proved difficult to convincingly remove contamination from EEG signals,” says Alan Gevins, a neuroscientist and founder of SAM Technology in San Francisco, a company that is developing EEG-based medical tests for evaluating attention and memory.
In trying to design a headset suitable for gaming, Emotiv and Neurosky face a daunting challenge: it must not require sticky gels, it must be simple enough for any user to slip on (no matter how oddly shaped his or her head), and it must use sluggish EEG responses to control quick actions. To see how they’re faring, I flew to California earlier this year to test both their devices–with Gevins’s help.
Sitting on a black leather couch at Emotiv’s sleek offices in downtown San Francisco, game producer Zachary Drake squeezes the Epoc headset onto my head. An outline of a head on the television screen in front of me indicates the quality of the signal coming from each of the headset’s 14 electrodes. Mine register mostly yellow–medium to poor.
I’m testing a game developed specifically to showcase the Epoc’s capabilities. In front of a pagoda set against a landscape of steep peaks and silhouetted trees, a martial-arts master commands me to lift a rock using only my thoughts. Trying to summon a Yoda-like intensity, I focus on the rock and make a lifting motion with my hand. (While Della Torre says it’s not necessary to physically make the movement, it often helps.) At first, the rock does nothing. Then it lifts slightly, wavers in the air, and sinks.