Coming soon: A mind-reading machine, say scientists who claim to have discovered a way of translating people's thoughts into words.
An international team, led by Prof Bradley Greger of Utah University, has been able to translate brain signals into speech using sensors attached to the surface of the brain for the first time.
The experimental breakthrough, which is up to 90 per cent accurate, offers a way to communicate for paralysed patients who cannot speak and could eventually lead to being able to read anyone thoughts, The Daily Telegraph reported.
"We were beside ourselves with excitement when it started working. It's just one of the moments when everything came together. We have been able to decode spoken words using only signals from the brain with a device that has promise for long-term use in paralysed patients who cannot now speak.
"I would call it brain reading and we hope that in two or three years it will be available for use for paralysed patients," Prof Greger was quoted as saying.
The team achieved the experimental breakthrough when it attached two button sized grids of 16 tiny electrodes to the speech centres of the brain of an epileptic patient who had part of his skull removed for another operation to treat his condition.
Using the electrodes, the scientists recorded brain signals in a computer as the patient repeatedly read each of 10 words that might be useful to a paralysed person: yes, no, hot, cold, hungry, thirsty, hello, goodbye, more and less.
Then they got him to repeat the words to the computer and it was able to match the brain signals for each word 76 per cent to 90 per cent of the time.
The computer picked up the patient's brain waves as he talked and did not use any voice recognition software.
Because just thinking a word and not saying it is thought to produce the same brain signals, Prof Greger and his team believe that soon they will be able to have translation device and voice box that repeats the word you are thinking.
What is more, the brains of people who are paralysed are often healthy and produce the same signals as those in able bodied people it is just they are blocked by injury from reaching the muscle.
The researchers said the method needs improvement, but could lead in a few years to clinical trials on paralysed people who cannot speak due to so-called 'locked-in' syndrome.
"This is proof of concept. We've proven these signals can tell you what the person is saying well above chance. But we need to be able to do more words with more accuracy before it is something a patient really might find useful.
"People who eventually could benefit from a wireless device that converts thoughts into computer-spoken words include those paralysed by stroke, disease and injury, Prof Greger said.
The findings have been published in the latest edition of the Neural Engineering journal.