A totally incommunicado ALS patient is able to 'speak' thanks to a brain implant

He could no longer move even his eyes, completely immobilized by amyotrophic lateral sclerosis (ALS), but he was able to say his name, that of his wife and that of their four-year-old son.

He didn't say it with his voice, but with his thoughts and thanks to a brain implant.

Spelling the five characters of his name would take another few minutes, but the achievement was historic: for the first time, a patient in that state of the disease managed to communicate.

“That moment was really magnificent”, remembers with emotion Arnau Espinosa, one of the neurotechnologists who have achieved this scientific milestone in Germany.

An achievement that opens the door to patient communication in very delicate situations and that is also a success in the development of technology that connects brains and machines.

Just 100 days before

his name, two implants had been placed in his brain in a Munich hospital, with 96 electrodes each, to identify his neuronal activity.

These waves are what allow this young man, 34 years old, whose name cannot be revealed for privacy, to communicate.

He perfectly preserves his mental abilities and can hear: that's how he receives the stimuli.

After a period of calibration and learning, he has been able to use his brain to mentally select the characters on a virtual keyboard.

Schematic representation of the implant and the interface for spelling with the computer. Nature Communications

Thus, letter by letter, he has been able to transmit discomfort, pain and other medical issues;

but also communicate with his family.

For example, when 253 days had passed since the implant, she was able to ask her son if she wanted to watch Disney's Robin Hood movie with him.

She also managed to ask for beer to be put in the feeding tube, to choose curried potatoes for lunch, or to have the album by the metal rock band Tool turned up loud.

“These are very tough projects,” acknowledges Espinosa, a researcher at the Wyss Center Foundation, “but one of the most pleasant moments for me was when we let the patient communicate freely and he correctly spelled his name: it is absolute proof that the patient is aware that he has a correct capacity to understand the outside world: I want to say my name and I say it”.

When no muscle responds

The scientific team proposed to the young man to try the implant when he could still communicate with the movement of the eye muscles to select his preferences, as the British physicist Stephen Hawking did.

In March 2019, the operation was carried out: a hole was opened in his skull to create an external connector that would communicate with the equipment installed in his house, a cabinet with computers that centralize all the activity.

It is not the first time that this system has been used, but it is the first time that communication has been established in this state of the degenerative disease, when the point of confinement is reached.

The patient maintains the correct cognitive functions, but the signals from his brain do not go out to the nervous system and he is no longer able to control any type of vital function and even needs a respirator.

The patient knew that he was going to be a father after being diagnosed with ALS "and decided to have it," explains Espinosa, adding: "I knew that the experience I would have with him was going to be in an atypical situation."

Appearance of the electrodes that are implanted in the patient's brain.Wyss Center

This achievement, published today in

, summarizes more than two years of work carried out even with the inconveniences derived from the pandemic, which forced scientists to work remotely with the patient.

Basically, the subject's brain selects in a binary way —yes or no— a row of letters or a specific letter, until he finishes writing what he wants.

"This study answers the age-old dilemma of whether people with complete locked-in syndrome, who have lost all voluntary muscle control, including eye or mouth movement, also lose their brain's ability to generate commands for communication." , explains Jonas Zimmermann, a neuroscientist at the Wyss Center in Geneva.

According to this foundation, dedicated to the research and development of brain technologies, it is expected that more than 300,000 people will live with ALS in 2040, and many of them will reach a state in which it is no longer possible to speak.

With further development, the approach described in this study could allow other people in advanced stages of the disease to maintain communication.

But the process is complex and the technology is still in its infancy, as Espinosa explains: capacities have been reduced again after a fruitful period of free communication.

The patient can no longer spell and is limited to answering yes or no to closed questions, because the system has lost sensitivity.

“The results are declining a bit, surely due to a technical problem.

The brain tries to protect itself from external bodies and creates a protective barrier with the electrode.

In addition, it adapts and the signal from the neural networks is much smaller”, explains the engineer, trained at the Polytechnic University of Catalonia.

far from the market

"These implants are far from being a generally applicable technology: they are prototypes, proofs of concept, a lot of work is needed to be able to have a commercial device on the market," says Espinosa.

That jump from experimentation to market is a field in which billions are being invested by companies like billionaire entrepreneur Elon Musk's Neuralink.

There is a technological part that can be applied to any patient, explains Espinosa, through those tiny needles that are stuck in the cortex, but where it is implanted varies depending on the person.

“Without studying it first, you don't know what type of neuron you're really getting a signal from, and each type of person has differently developed neural networks.

You have to see which electrodes are associated with which activity for each patient and see how you are going to be able to use them”, explains the researcher.

What's more, the system needs to be calibrated for each brain, but also before each session: “It's not constant, you can't plug something into it and expect it to be the same tomorrow.

We are trying to automate it as much as possible, but there is a lot of work to do for systems and algorithms to adapt to brain signals from session to session”, he acknowledges.

You can write to us at

Exclusive content for subscribers

read without limits

subscribe

I'm already a subscriber