Mastering the Brain-Computer Interface

At Johns Hopkins University, engineers are learning to translate between the neural signals of the brain and the machine language of a prosthetic arm

4 min read

The first human clinical trials of a brain implant intended to control a prosthetic arm are slated for 2009 at the Johns Hopkins University Biomedical Instrumentation and Neuroengineering Laboratory, in Baltimore. In one brightly lit room, a young volunteer named Rob Rasmussen sits with his head strapped into a tight-fitting cap, inside which 64 electrodes monitor his brain waves. The electrodes detect the electrical activity caused by neurons firing inside the motor areas of his brain and send the raw impulses to a nearby instrument to be digitized. The digitized signals are translated into real-time traces that scrawl across two wide-screen monitors. One of the monitors shows the 64 simultaneous channels of brain-wave recordings. The other, larger monitor is devoted to two entirely different traces--those of the mu bands. These are the keys to controlling a prosthetic arm with the mind.

Mu bands are an abstract feature of the brain waves picked up by the electrodes: they provide a broad reflection of what's happening in the motor areas of the brain. In this case, they characterize what Rasmussen is thinking about doing with his hands. The mu bands maintain a regular rhythm that desynchronizes in the left side of the brain when you wiggle a finger or arch your foot on the right side of your body (and vice versa). That rhythm also responds the same way--and this is key--to merely thinking about doing those things. So to disturb the waves of his mu bands, Rasmussen thinks about moving his hands. To let the waves return to their natural rhythm, he stops thinking about moving his hands. His actual hands are resting lightly on the arms of his chair. They don't even twitch.

Keep Reading ↓Show less

This article is for IEEE members only. Join IEEE to access our full archive.

Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, podcasts, and special reports. Learn more →

If you're already an IEEE member, please sign in to continue reading.

Membership includes:

  • Get unlimited access to IEEE Spectrum content
  • Follow your favorite topics to create a personalized feed of IEEE Spectrum content
  • Save Spectrum articles to read later
  • Network with other technology professionals
  • Establish a professional profile
  • Create a group to share and collaborate on projects
  • Discover IEEE events and activities
  • Join and participate in discussions

Are You Ready for Workplace Brain Scanning?

Extracting and using brain data will make workers happier and more productive, backers say

11 min read
A photo collage showing a man wearing a eeg headset while looking at a computer screen.
Nadia Radic

Get ready: Neurotechnology is coming to the workplace. Neural sensors are now reliable and affordable enough to support commercial pilot projects that extract productivity-enhancing data from workers’ brains. These projects aren’t confined to specialized workplaces; they’re also happening in offices, factories, farms, and airports. The companies and people behind these neurotech devices are certain that they will improve our lives. But there are serious questions about whether work should be organized around certain functions of the brain, rather than the person as a whole.

To be clear, the kind of neurotech that’s currently available is nowhere close to reading minds. Sensors detect electrical activity across different areas of the brain, and the patterns in that activity can be broadly correlated with different feelings or physiological responses, such as stress, focus, or a reaction to external stimuli. These data can be exploited to make workers more efficient—and, proponents of the technology say, to make them happier. Two of the most interesting innovators in this field are the Israel-based startup InnerEye, which aims to give workers superhuman abilities, and Emotiv, a Silicon Valley neurotech company that’s bringing a brain-tracking wearable to office workers, including those working remotely.

Keep Reading ↓Show less