Science

Scientists use brain activity analysis to reconstruct words heard by test subjects

Scientists use brain activity analysis to reconstruct words heard by test subjects
Scientists have developed technology that is able to reconstruct words heard by test subjects, through analyzing their brain activity (Photo: Elvert Barnes)
Scientists have developed technology that is able to reconstruct words heard by test subjects, through analyzing their brain activity (Photo: Elvert Barnes)
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Scientists have developed technology that is able to reconstruct words heard by test subjects, through analyzing their brain activity (Photo: Elvert Barnes)
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Scientists have developed technology that is able to reconstruct words heard by test subjects, through analyzing their brain activity (Photo: Elvert Barnes)
Electrodes on the temporal lobe of one of the test subjects (Image: UC Berkeley)
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Electrodes on the temporal lobe of one of the test subjects (Image: UC Berkeley)

Last September, scientists from the University of California, Berkeley announced that they had developed a method of visually reconstructing images from peoples' minds, by analyzing their brain activity. Much to the dismay of tinfoil hat-wearers everywhere, researchers from that same institution have now developed a somewhat similar system, that is able to reconstruct words that people have heard spoken to them. Instead of being used to violate our civil rights, however, the technology could instead allow the vocally-disabled to "speak."

Epilepsy patients were enlisted for the study, who were already getting arrays of electrodes placed on the surface of their brains to identify the source of their seizures. The scientists used these electrodes to monitor the electrical activity in a region of their brains' auditory system, known as the superior temporal gyrus (STG). From there, it was a matter of observing the specific activity patterns that occurred when the subjects heard certain words.

Electrodes on the temporal lobe of one of the test subjects (Image: UC Berkeley)
Electrodes on the temporal lobe of one of the test subjects (Image: UC Berkeley)

When the electrodes' data was applied to a computational model, the computer was able to actually reproduce the sounds that had been heard - sort of. Although the noises made by the computer were somewhat garbled, they were close enough to the original words that the scientists were better able to identify those words than would be possible otherwise.

According to study leader Brian N. Pasley, there is evidence that the perception of real sounds and imagined ones may result in similar STG activity. If so, then the technology could perhaps someday be used in a gadget that "vocalizes" words or sentences thought out by people unable to speak.

"This research is based on sounds a person actually hears, but to use this for a prosthetic device, these principles would have to apply to someone who is imagining speech," he explained. "If you can understand the relationship well enough between the brain recordings and sound, you could either synthesize the actual sound a person is thinking, or just write out the words with a type of interface device."

A paper on the UC Berkeley research was published yesterday in the journal PLoS Biology.

5 comments
5 comments
Foxy1968
Now all they have to do is develop a rTMS device capable of targeting neurones and you will be able to communicate directly to a person without the need for invasive sergery once the system knows what words are stored in what location in your brain. All you have to do is stimulate those neurones and the person will receive the information as if they had actually heard it.
Once this level of targeting has been achieved repairing pathways in the brain will become possible and using the same device at a different frequency you will be able to remove unwanted pathways that cause neurological disorders.
TheRogue1000
You may be sure, however, that if this *can* be used to violate our civil rights, it WILL be done.
Ted Coombs
Now, images to text for the deaf...
Bob Tackett
Imagine Dr. Hawking being able to speak and write at normal speed.
Eleni Muller
If this becomes operational, you can say, with certainty, it will eventually be used to violate civil rights. The only way I won\'t see that happening is if everyone in charge of this nation wakes up compassionate, honest and respectful of individual freedom.