- Apr 17, 2020
- 542
Letter by painstaking letter, a man in a completely locked-in state was able to formulate words and sentences using only his thoughts.
Researchers used auditory neurofeedback to help the patient, who has amyotrophic lateral sclerosis, learn to manipulate his own brain activity.
In 2020 Ujwal Chaudhary, a biomedical engineer then at the University of Tübingen and the Wyss Center for Bio and Neuroengineering in Geneva, watched his computer with amazement as an experiment that he had spent years on revealed itself. A 34-year-old paralyzed man lay on his back in the laboratory, his head connected by a cable to a computer. A synthetic voice pronounced letters in German: “E, A, D…”
The patient had been diagnosed a few years earlier with amyotrophic lateral sclerosis, which leads to the progressive degeneration of brain cells involved in motion. The man had lost the ability to move even his eyeballs and was entirely unable to communicate; in medical terms, he was in a completely locked-in state.
Or so it seemed. Through Dr. Chaudhary’s experiment, the man had learned to select — not directly with his eyes but by imagining his eyes moving — individual letters from the steady stream that the computer spoke aloud. Letter by painstaking letter, one every minute or so, he formulated words and sentences.
“Wegen essen da wird ich erst mal des curry mit kartoffeln haben und dann bologna und dann gefuellte und dann kartoffeln suppe,” he wrote at one point: “For food I want to have curry with potato then Bolognese and potato soup.”
Dr. Chaudhary and his colleagues were dumbstruck. “I myself could not believe that this is possible,” recalled Dr. Chaudhary, who is now managing director at ALS Voice gGmbH, a neurobiotechnology company based in Germany, and who no longer works with the patient.
The study, published on Tuesday in Nature Communications, provides the first example of a patient in a fully locked-in state communicating at length with the outside world, said Niels Birbaumer, the leader of the study and a former neuroscientist at the University of Tübingen who is now retired.
Dr. Chaudhary and Dr. Birbaumer 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 retracted after an investigation by the German Research Foundation concluded that the researchers had only partially recorded the examinations of their patients on video, had not appropriately shown details of their analyses and had made false statements. The German Research Foundation, finding that Dr. Birbaumer committed scientific misconduct, imposed some of its most severe sanctions, including a five-year ban on submitting proposals and serving as a reviewer for the foundation.
The agency found that Dr. Chaudhary had also committed scientific misconduct and imposed the same sanctions for a three-year period. Both he and Dr. Birbaumer were asked to retract their two papers, and they declined.
The investigation came after a whistle-blower, Martin Spüler, a researcher, raised concerns about the two scientists in 2018.
Dr. Birbaumer stood by the conclusions and has taken legal action against the German Research Foundation. The results of the lawsuit are expected to be published in the next two weeks, said Marco Finetti, a spokesman for the German Research Foundation. Dr. Chaudhary says his lawyers expect to win the case.
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