From The Sunday Times, London, May 30, 2011
Quote:
SCIENTISTS have found a way to “mind read”, peering into the deepest recesses of the brain to watch words forming as people think and speak.
Using networks of electrodes implanted into people’s skulls, the researchers have located brain areas that generate the 40-odd sounds from which the English language is constructed.
They found each sound had a unique signal that could be seen forming as subjects expressed them out loud or in their heads.
The breakthrough could eventually allow scientists to translate people’s thoughts into words, potentially allowing those with severe paralysis or other disabilities to speak via a computer.
In a research paper, Dr Eric Leuthardt, Director of the Centre for Innovation in Neuroscience and Technology at Washington University, St Louis, said his team had isolated signals corresponding to four of the 40 sounds.
“What it shows is that the brain is not the black box that we have philosophically assumed it to be for generations past,” Dr Leuthardt said. “I’m not going to say that I can fully read someone’s mind. I can’t. But I have evidence now that it is possible.”
Dr Leuthardt and his colleagues based their research on four people suffering from severe epilepsy who had 64 electrodes implanted in their heads, on the surface of the brain, to try to find the causes of their fits.
The arrays were also able to monitor the parts of the brain thought to generate language: the motor cortex, Wernicke’s area and Broca’s area. Dr Leuthardt was able to use them to search for the signals corresponding to the formation of sounds, known as phonemes.
The subjects were asked repeatedly to make four of the sounds (“oo”, “ah”, “eh” and “ee”), while the scientists picked out the electrical signals.
Since publishing his study in the Journal of Neural Engineering, Dr Leuthardt has taken the research further and identified signals corresponding to many more phonemes, although this work has not yet been published.
Leuthardt concludes:
“We want to see if we cannot just detect when you’re saying ‘dog’, ‘tree’, ‘too’l or some other word, but also learn what the pure idea of that looks like in your mind… It’s exciting and a little scary to think of reading minds, but it has incredible potential for people who can’t communicate or are suffering from other disabilities.”
