Brain Implant Allows Fully Paralyzed Patient to Communicate

In 2020, Ujjwal Chowdhury, a biomedical engineer at the University of Tિંગbingen and the Wyss Center for Bio and Neuroengineering in Geneva, looked at his computer with amazement as an experiment he spent years publishing himself. A 34-year-old paralyzed man was sleeping on his back in the laboratory, his head connected to a computer by a cable. Syntactically pronounced German letters: “E, A, D …”

The patient was diagnosed with amyotrophic lateral sclerosis a few years ago, leading to progressive degeneration of the brain cells involved in motion. The man also lost the ability to move his eyelids and was completely unable to communicate; Medically, he was in a completely closed condition.

Or so it seemed. By Dr. In Choudhury’s experiment, man – not directly with his eyes but with the idea of ​​moving his eyes – learned to select individual characters from a computer speaking loud static stream. A diligent letter, one or more every minute, he composed words and sentences.

“Vegan essen da weird ich erst mal des curry meat cartofelan heben und den bologna und dan gefult und den cartofellan soup,” he wrote at one point: “for food I want to boil with bolognese and potato soup after potatoes.”

Dr. Chaudhry and his associates were stunned. “I did not believe that this was possible,” said Dr. Choudhury, who is now managing director at ALS Voice gGmbH, a German-based neurobiotechnology company and who no longer works with patients.

The study, published Tuesday in Nature Communications, provides the first example of a patient in a completely closed state engaging in lengthy conversations with the outside world, said Niels Birbaumer, study leader and former neuroscientist at the University of Tિંગbingen. Who is now retired.

Dr. Chaudhary and Dr. Birbaum conducted two similar experiments in 2017 and 2019 on patients who were completely locked-in and reported that they were able to communicate. Both studies were withdrawn after an investigation by the German Research Foundation found that researchers only partially recorded their patients’ examination on video, did not accurately disclose the details of their analysis, and made false statements. The German Research Foundation, finds that Dr. Birbaumar committed scientific misconduct, imposing some of its most severe sanctions, including a five-year ban on submitting proposals and serving as a reviewer for the foundation.

The agency learned that Dr. Chaudhary also committed scientific misconduct and imposed similar sanctions for a period of three years. He and Dr. Birbaumer was asked to withdraw his two papers, and they refused.

The investigation came after a whistle-blower, Martin Speller, a researcher, expressed concern about two scientists in 2018.

Dr. Birbaumer is adamant on the findings and has taken legal action against the German Research Foundation. The results of the trial are expected to be published in the next two weeks, said Marco Finetti of the German Research Foundation. Dr. Chaudhry says his lawyers expect him to win the case.

The German Research Foundation has no information about the publication of the current study and will investigate it in the coming months, Mr. Finetti said. In an email, a representative for Nature Communications, who asked not to be named, declined to comment on the details of how the study was verified but expressed confidence in the process. “We have strict policies in place to safeguard the integrity of the research we publish, including ensuring that research is conducted at high ethical standards and is reported in a transparent manner,” the representative said.

“I would say it’s a solid study,” said Natalie Mrachaz-Kirsting, a brain-computer interface researcher at the University of Freiburg in Germany. She was not involved in the study and was aware of the previously withdrawn paper.

But Brendan Ellis, a researcher at the University of California San Diego, expressed reservations. “Like the other work of Birbaumer, this work should be taken with a huge mountain of salt in mind considering its history,” said Dr. Said Alice. He noted that in a paper published in 2017, his own team described being able to communicate with completely locked-in patients with basic “yes” or “no” answers.

The results are promising for patients with similar unresponsive situations, including minimally invasive and unhealthy conditions, as well as an increasing number of people diagnosed with ALS worldwide each year. That number is projected to reach 300,000 by 2040.

“It’s a game-changer,” said Steven Lores, a neurologist and researcher who led the Coma Science Group at the University of Li લીge in Belgium and was not involved in the study. Technology could have a moral impact on discussions around euthanasia for patients in a locked-in or vegetative state, he added: “It’s really nice to see this move forward, giving patients a voice in their own decisions.”

Numerous methods have been used to communicate with unresponsive patients. Some include basic pen-and-paper methods developed by family members. In others, caregivers point to or speak the names of objects and look for micro-responses – blinking, stroking the patient’s fingers.

In recent years, a new method has taken center stage: brain-computer interface technology, which aims to translate a person’s brain signals into commands. Entrepreneurial billionaires like research institutes, private companies and Elon Musk have invested heavily in technology.

The results are mixed but inevitable: patients simply move their limbs using their ideas, and patients with stroke, multiple sclerosis and other conditions once again communicate with loved ones.

What scientists haven’t been able to do so far, however, is interacting extensively with people like the man in the new study who showed no movement.

In 2017, before becoming fully locked-in, the patient used eye movements to communicate with his family. With the expectation that he would soon lose this ability as well, the family asked for an alternative communication system and Dr. Chaudhary and Dr. Birbaumar, a pioneer in the field of brain-computer interface technology, who worked closely together.

With the permission of the man, Dr. Jens Lehmberg, a neurosurgeon and author of the study, implanted two small electrodes in areas of the human brain involved in controlling movement. Then, for two months, the man was asked to imagine waving his arms, hands and tongue to see if he would produce a clear brain signal. But the effort did not yield anything credible.

Dr. Birbamar then suggested the use of auditory neurofeedback, an unusual technique by which patients are trained to actively manipulate their own brain activity. Man was first introduced with a note – high or low, corresponding to yes or small. This was his “target tone” – the note he had to match.

It was then played another note, which maps on the brain activity detected by the implanted electrodes. By focusing – and imagining moving his eyes, to effectively dial up or down his brain activity, he was able to change the pitch of the second tone to match the first. As he did so, he received real-time feedback on how the note changed, allowing him to raise the pitch when he wanted to say yes or lower it for no.

This approach had immediate results. By trying the man’s first day, he was able to change the second tone. Twelve days later, he managed to compare the second to the first.

“That was when everything became consistent, and he could reproduce that pattern,” said Jonas Zimmerman, a neuroscientist at the Wyss Center and author of the study. When the patient was asked what he envisioned changing his own brain activity, he replied: “Eye movements.”

In the following year, the man used this skill to create words and sentences. The scientists borrowed a communication strategy that the patient used with his family while he could still move his eyes.

They grouped the letters into a set of five colors. The computerized voice first listed the colors, and the man answered “yes” or “no”, depending on the letter he wanted to choose. The voice then listed each letter, which he chose equally. He repeated these steps set by letter, letter by set, to clarify the whole sentences.

On the second day of his spelling attempt, he wrote: “First I thank Niels and his Birbomer.”

Some of her sentences include instructions: “Mommy head massage” and “Everyone should use the gel on my eyes more often.” Others described cravings: “goulash soup and sweet pea soup.”

Of the 107 days the man spent in spelling, 44 resulted in understandable sentences. And when there was a huge variability in speed, he wrote at a speed of about one letter per minute.

“Wow, it blew my mind,” Dr. Marchez-Kirsting. She speculated that lock-in patients who could keep their minds excited could experience a longer, healthier life.

Dr. However, Marchez-Kirsting insisted that the study was based on one patient and would need to be tested on several others.

Other researchers were also cautious in accepting the findings.

“This approach is practical, so we still need to learn a lot,” said Neil Thakur, chief mission officer of the ALS Association.

At this stage the technology is too complex to operate patients and families. Making it more user friendly and speeding up communication will be crucial, said Dr. Chaudhary said. Until then, he said, the patient’s relatives would be satisfied.

“You have two options: no communication or communication on one letter per minute,” he said. “What do you like?”

Perhaps the biggest concern is timing. Three years have passed since the first implant was implanted in a patient’s brain. Since then, their answers have become significantly slower, less reliable, and often impossible to discern. Zimmerman, who now cares for the patient at the Wyss Center.

The reason for this decline is not clear, but Dr. Zimmermann thought it might have been caused by technical problems. For example, electrodes are nearing the end of their life. However, it would be foolish to change them now. “It’s a risky process,” he said. “Suddenly you came into contact with a new type of bacteria in the hospital.”

Dr. Zimmerman and others at the Wyss Center are developing wireless microelectrodes that are safer to use. The team is also exploring other non-invasive techniques that have proved fruitful in previous studies on patients who are not locked-in. “As much as we want to help people, I think it’s very dangerous to have false hopes,” he said. Zimmerman said.

At the same time, Dr. Lores of Coma Science Group said there is no point in fostering a sense of “false despair” when competent innovations are appearing on the horizon.

“I’m very excited as a caregiver, as a therapist,” he said. “I think it’s wonderful that we offer this new scientific insight and technology in very sensitive and dramatic situations.”

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