A quadriplegic paralyzed from the neck down was able to generate letters on a computer screen in real time by imagining himself writing with a pen in his hand.
To accomplish the feat, the scientists used chips that were implanted in the patient’s brain to detect the brain patterns involved in writing each letter. Electrodes transferred these patterns to an algorithm that can read and translate brain activity – the movement detected in the brain that corresponds to a letter became the version typed on a screen.
The description of the experiment, which was carried out with the apparatus, a kind of brain-computer interface (BCI, English abbreviated), was published on May 12 in the journal Nature. This is the first time scientists have identified handwriting-related brain patterns and turned them into text.
The work was carried out by researchers from Stanford, Brown, and Harvard Universities, all in the United States.
The machine enabled the test participant, a 65-year-old man, to type at a rate of 90 characters per minute – similar to what people in the same age group can do with a mobile phone, so an article published in 2019 found writing using the Interface rated 94% correctly.
Some of the researchers involved in the research had previously developed a system that would allow a person to write by imagining themselves moving their arm like a cursor on a computer screen and clicking on the letters. The device allowed writing at a speed of 40 characters per minute.
The participant in the most recent experiment was given two chips in the part of the brain that controls hand and arm movements as part of another study called BrainGate2, led by Brown University.
Some of the people who lose their body movement due to degenerative diseases or accidents can benefit from interfaces such as those developed by American researchers. Because in these people, the brain commands responsible for the movements remain active. The key is to translate commands into actions.
The British physicist Stephen Haking (1942-2018) used a brain-machine interface for communication. Hawking’s device used a sensor that sensed the contractions in his cheek and translated them into letters and words.
Hawking lost his body movement due to amyotrophic lateral sclerosis, a degenerative disease of the nervous system.
The device enabled the scientist to work, write books and give lectures – Hawking was one of the most productive mediators of science in his lifetime.
Now American researchers must test the system that writes with thoughts about people who have lost the ability to speak.
The study published in Nature is a big step forward for the BCI space, but scientists say this is just the beginning. “More experimentation with more participants and improvements to the system are needed. Even so, we believe that the future of intracortical brain-machine interfaces is bright,” the researchers write.