An experimental device that turns thoughts into text has allowed a man who was left paralyzed by an accident to construct sentences swiftly on a computer screen. The man was able to type with 95% accuracy just by imagining he was handwriting letters on a sheet of paper, a team reported Wednesday in the journal Nature.
“What we found, surprisingly, is that he can type at about 90 characters per minute," says Krishna Shenoy of Stanford University. The device would be most useful to someone who could neither move nor speak, says Dr. Jaimie Henderson, a professor at Stanford and co-director, with Shenoy, of the Stanford NPTL.
“We can also envision it being used by someone who can't move but wants to use email,” Henderson says, “or, say, a computer programmer who wants to go back to work.”
The idea of decoding the brain activity involved in handwriting is 'just impressive, says John Ngai, who directs the National Institutes of Health's BRAIN Initiative, which helped fund the research. "But it was only on one subject in a laboratory setting," Ngai says. "So at the moment it's a great example of proof of principle."
The man who agreed to test the device is unable to move his arms and legs as the result of an accident. A few years ago, the man agreed to take part in a study of an experimental system called BrainGate2. It allows people who are paralyzed to control computers and other devices using only their thoughts.
The system relies on devices surgically implanted near the part of the brain that controls movement. In previous studies, participants had learned to control a computer cursor or robotic arm by imagining they were moving their hands.
This time, Henderson, Shenoy and a team of scientists had the man imagine he was writing individual letters by hand while a computer monitored the electrical activity in his brain. Eventually, the computer learned to decode the distinct pattern of activity associated with every letter of the alphabet as well as several symbols. Once that process is complete, Shenoy says, “We can determine if the letter you wrote is an A or a B or a C and then show on the screen and you're able to spell out words and sentences and so forth one letter at a
In previous experiments, participants had been able to use their thoughts to “point and click” at letters on a screen. But that approach was much slower than imagined handwriting. Also, because the new system relies on familiar thoughts, the participant was able to use it almost immediately.
8. By imagining handwriting, a person can type about ________ correct characters per minute.
9. Which can replace the underlined word “envision“ in the third paragraph?
A.Guide. | B.Imagine. | C.Suggest. | D.Promote. |
10. What is John Ngai's attitude to the handwriting approach?
A.Favorable. | B.Cautious. | C.Ambiguous. | D.Disapproving. |
11. In order to spell out words, the participants should________.
A.have the electrical activity in their brain monitored |
B.first learn to take control of a computer cursor or robotic arm |
C.be able to use their fake hands to “point and click” at letters on a screen |
D.have devices implanted near the brain part controlling thinking |
12. Which section of a website may this text appear?
A.Entertainment. | B.Health. | C.Education. | D.Medicine. |