Then, with the electrodes still in the brain, the researchers did very simple speech tests; for example, four simple-sounding words. They looked at the electrical "signatures" of each word or sound when it was being spoken or merely thought about to see if they could be distinguished from each other.
They could, and so Leuthardt and his team then programmed the signatures into the computer to correspond with certain instructions, such as moving the cursor left or right.
When the person said or thought the word or sound, they were basically able to manipulate the computer with their mind or speech with 68 percent to 91 percent accuracy within 15 minutes.
"We're starting to parse apart the different components of human speech and we're excited because speech is very rich. There's a lot of information we can convey with that," said Leuthardt, who is assistant professor of neurosurgery and of biomedical engineering at Washington University in St. Louis.
Similar brain-computer interfaces have been used to restore the sight of one patient and stimulate limb movement in others.
The scientists envision one day having tiny, permanent implants in people's brains.
And not just the brains of disabled people.
"It would be a way to interface with your computer in a much more rich relationship than just a keyboard and a mouse," Sanchez said.
The University of Miami has more on neuroprosthetics.
SOURCES: Eric C. Leuthardt, M.D., assistant professor, neurosurgery and biomedical engineering, Washington University in St. Louis; Justin C. Sanchez, Ph.D., associate professor, biomedical engineering, and director, Neuroprosthetics Research Group, University of Miami Miller School of Medicine; April 7, 2011, Journal of Neural Engineering
All rights reserved