Researchers have just created a new means of communication.
- Certain pathologies or certain accidents can cause you to permanently lose the ability to speak.
- To help these people communicate, researchers have designed a system capable of decoding words emitted only in the head with a degree of precision never before achieved.
- Arrays of microelectrodes were thus implanted in the brains of two men suffering from quadriplegia.
It’s a small revolution that could help a large number of people who have lost the ability to speak. A team of researchers has developed a system capable of decoding words emitted only in the head with a degree of precision never before achieved.
The interface tested on 8 words
To do this, microelectrode arrays were implanted in the brains of two men suffering from quadriplegia (paralysis of all four limbs), one aged 33 and the other 39 years old. The scientists targeted their primary somatosensory cortex and the supramarginal gyrus (SMG), a region of the brain that had never before been explored for this type of study.
The interface was tested on six existing words (battlefield, cowboy, python, spoon, swimming, telephone) and two invented words (“nifzig”, “bindip”), to determine whether the words needed to make sense for the system to work effectively. Participants saw each word on a screen and then heard them spoken. Then they were asked to imagine saying the same word for 1.5 seconds.
The device allowed the researchers to decode, in real time, the activity of the SMG while the participants thought about each word. For one of the participants, the accuracy reached 79%, “barely less than the decoding of vocal speech”, explain the members of the research team in a note. “For the other participant, the accuracy was 23%.”
The new technology still needs to be refined
“This technology could be particularly useful for people who no longer have any means of movement,” said study leader Sarah Wandelt. “I’m thinking, for example, of locked-in syndrome,” she added.
The new technology will still need to be refined and then tested on a larger group of people and using more words, but the study demonstrates that the SMG is a promising brain region to target.
“This study is important because it is, to my knowledge, the first realization of a real-time speech brain-computer interface based on unit recordings in the SMG,” commented Blaise Yvert, from the Grenoble Institute of Neurosciences.
The study appeared in the magazine Nature Human Behavior.