It sounds like the stuff of science fiction. A quadriplegic controls the movement of his wheelchair simply by thinking about it. Or a stroke victim with a speech impairment can spell out words on a computer by thinking about the letters.
Such feats may be only a few years away thanks in part to research into thought-controlled computing at Arizona State University’s Harrington Department of Bioengineering.
Though it may sound unbelievable, ASU researchers have already proven the basic concepts in experiments with laboratory animals. The next step will be to do it in humans — use brain waves to control the movement of robots and the operation of computers.
It’s done by using electrodes to detect electrical pulses produced by neurons in the brain. The human brain consists of trillions of neurons, the basic unit that stores and processes information. When a neuron is working, it sends out electrical pulses. Those pulses can be captured by electrodes that in turn are connected by wires to a computer that controls a robot or other devices, allowing that device to be ultimately controlled by the brain activity.
In the process of conducting the research, scientists are learning more about how the brain works, said Dr. Jiping He, a professor in the department who specializes in research on neural and musculoskeletal adaptation.
Under normal conditions, the brain communicates with the world through verbal language and body movements and expressions. What researchers at ASU and other universities are trying to do is build another pathway between the brain and the external world.
"We are trying to see if we can develop a new neural interface that allows us to peek into the brain and see what electrical and chemical processes are going on between neurons," he said.
In the most complex task they have accomplished to date, ASU researchers have trained a monkey to move a robot arm about eight inches just by neural activ- ity — in other words, by thinking about it.
"What we have done is to train a group of neurons to interact with a computer, which in turn controls an artificial arm. It is colearning between the neurons and the computer," He said.
The research could someday benefit humans who have suffered stroke or spinal chord injuries — any condition in which speech or movement are impaired but the brain can still function.
"If you can still think, you can train part of the brain to control an artificial arm or the movement of a wheelchair," He said. "It could help someone regain a degree of independent living."
He also is working with a lab in China to train humans to communicate by using their brains to move a cursor on a computer screen to identify letters and spell out words.
The biggest obstacles are technical in nature, such as developing electrodes that can reliably detect electrical pulses from the neurons. Future improvements could allow pulses to be detected externally without the need to implant electrodes in the brain. Also it may be possible to develop wireless means to relay the signals to the computer.
Such problems could be overcome within three to five years, maybe sooner, He predicted.
The ASU research is being funded by the National Institutes of Health, while the Department of Defense is contributing funds to support ASU’s Neural Muscular Control Lab, where the research is conducted. The Pentagon sees the possibility that future pilots and soldiers could make faster decisions in combat, such as maneuvering an aircraft simply by thinking about it.
Other universities are conducting similar research, including Duke, Brown, Cal Tech and Emory University in Atlanta. Emory has advanced to the point of working with paralyzed human patients, said Steve Helms Tillery, an ASU research professor.
Future work at ASU will focus on learning more about how the brain works, such as which brain signals control hand movements, He said.