High Speed Typing Brain-Computer Interface

The ancient art of handwriting has just pushed the field of brain-computer interface (BCI) to the next level. Researchers have devised a system that allows a person to communicate directly with a computer from his brain by imagining creating handwritten messages. The approach enables communication at a rate more than twice as fast as previous typing-by-brain experiments.

Researchers at Stanford University performed the study on a 65-year-old man with a spinal cord injury who had had an electrode array implanted in his brain. The scientists described the experiment recently in the journal Nature.

The big news from this paper is the very high speed,” says Cynthia Chestek, a biomedical engineer at the University of Michigan, who was not involved in the study. “It’s at least half way to able-bodied typing speed, and that’s why this paper is in Nature.”

For years, researchers have been experimenting with ways to enable people to directly communicate with computers using only their thoughts, without verbal commands, hand movement, or eye movement. This kind of technology offers a life-giving communication method for people who are “locked in” from brainstem stroke or disease, and unable to speak.

Successful BCI typing-by-brain approaches so far typically involve a person imagining moving a cursor around a digital keyboard to select letters. Meanwhile, electrodes record brain activity, and machine learning algorithms decipher the patterns associated with those thoughts, translating them into the typed words. The fastest of these previous typing-by-brain experiments allowed people to type about 40 characters, or 8 words, per minute.

That we can do this at all is impressive, but in real life that speed of communication is quite slow. The Stanford researchers were able to more than double that speed with a system that decodes brain activity associated with handwriting. In the new system, the participant, who had been paralyzed for about a decade, imagines the hand movements he would make to write sentences.

We ask him to actually try to write—to try to make his hand move again, and he reports this somatosensory illusion of actually feeling like his hand is moving,” says Frank Willett, a researcher at Stanford who collaborated on the experiment.

A microelectrode array implanted in the motor cortex of the participant’s brain records the electrical activity of individual neurons as he tries to write. “He hasn’t moved his hand or tried to write in more than ten years and we still got these beautiful patterns of neural activity,” says Willett.

The new findings, published online in Nature, could spur further advances benefiting hundreds of thousands of Americans, and millions globally, who’ve lost the use of their upper limbs or their ability to speak due to spinal-cord injuries, strokes or amyotrophic lateral sclerosis, also known as Lou Gehrig’s disease, said Jaimie Henderson, MD, professor of neurosurgery.

This approach allowed a person with paralysis to compose sentences at speeds nearly comparable to those of able-bodied adults of the same age typing on a smartphone,” said Henderson, the John and Jene Blume — Robert and Ruth Halperin Professor.” The goal is to restore the ability to communicate by text.”

The participant in the study produced text at a rate of about 18 words per minute. By comparison, able-bodied people of the same age can punch out about 23 words per minute on a smartphone.

Surce: https://med.stanford.edu/

The Mind Controls Remotely Videogames

Scientists in Switzerland have developed a system which allows people with severely-impaired motor functions, such as quadriplegia, to use video games using only the power of their brain.

Samuel Kunz, who was paralysed after an accident, uses the brain-computer interface to control an avatar through a race course in a specially-designed computer game called ‘Brain Driver’. The ultimate aim of the research is to develop technology to control devices such as wheelchairs for those with a limited ability to move. Kunz, who is taking part in the trial, is able to ‘pilot’ the digital race-car using only his brain signals transmitted to a computer via electrodes placed on his head.


These electrodes are connected to an amplifier and then to the computer and to our algorithms in the end. The algorithms are then calculating the brain signal and sending commands to the game that our pilot can actually control,” Dr. Rea Lehner, a neuroscientist at ETH Zurich explained. Lehner added Kunz is training his mind by imagining certain actions which are then translated into signals to control the race car. Thinking about moving his left hand makes the car turn left, thinking about moving his right hand turns the car right, and moving both together makes the car go straight. A fourth command – fully relaxing and clearing his mind – slows the car down. Kunz said it has taken a lot of practise to train his mind to control the game; which will be made even more difficult in a stadium full of people. He will be among those taking part in a special championship next year called Cybathlon in which people with physical disabilities compete against each other using state-of-the-art technology.

I have to be very concentrated. The connection between my fingers and my brain is not there anymore. I still try to move my fingers just in my head and so that needs a lot of concentration to do it exactly the same way every time,” Kunz told Reuters during a training session in Zurich.

Source: https://www.reuters.com/