For hundreds of thousands of people living across the globe, communication isn’t as straightforward as moving your mouth or raising a hand. In the U.S., nearly 30,000 people live with amyotrophic lateral sclerosis—better known as ALS or Lou Gehrig’s disease. It’s a terrifying and incurable disease that progressively robs affected individuals of their ability to move, interact, and communicate.
While there are assistive communication devices (think physicist Stephen Hawking’s speech-generating device with its iconic robotic drawl) that rely on eye or facial muscle movement, they eventually fail for some people who become completely paralyzed. ALS patients in this locked-in state can hear and understand what’s going around them but are powerless to respond.
The good news, though, is that a team of scientists is fixing to change that. In a new study published Tuesday in the journal Nature Communications, Swiss and German researchers helped a 34-year-old man with severe ALS to communicate through a brain-computer interface (BCI) implanted in his brain. This new approach aims to revolutionize communication devices for patients with ALS and potentially other neurological disorders that severely impair speech and other movements.
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Two microelectrode arrays, each 3.2 mm square, were inserted into the surface of the motor cortex—the part of the brain responsible for movement. Each array has 64 needle-like electrodes that record neural signals.
Courtesy Wyss Center“This study answers a long-standing question about whether people with complete locked-in syndrome (CLIS)—who have lost all voluntary muscle control, including the movement of the eyes or mouth—also lose the ability of their brain to generate commands for communication,” Jonas Zimmermann, a neuroscientist at the Wyss Center for Bio and Neuroengineering in Switzerland and a co-author of the new study, said in a press release. “Successful communication has previously been demonstrated with BCIs in individuals with paralysis. But, to our knowledge, ours is the first study to achieve communication by someone who has no remaining voluntary movement and hence for whom the BCI is now the sole means of communication.”
The new ALS implant uses electrodes to pick up brain signals that are fired. While being shown in real-time the spikes of his brain activity, the 34-year-old study participant was asked to mentally match sound tones with each other. The new BCI system learned how to detect whether the participant was saying “yes” or “no” based solely on his brain activity. Using this strategy, he later learned to select letters one at a time, by saying yes or no, to form words and entire phrases from a speller program reading aloud the alphabet.
Though BCI technology is still in its infancy, a rush of research in recent years has raised its profile among the public—and not always positively (read: Elon Musk’s company Neuralink). Some experts are worried about what could happen to someone if their implant was removed midway during a clinical trial, how long these devices actually last, and whether the company would cover upgrades regardless if the clinical trials prove successful.
Even the authors of this latest study have been in hot water over previous BCI trials. In September 2019, the German Research Foundation (DFG) charged co-authors Niels Birbaumer and Ujwal Chaudhary with scientific misconduct related to similar research conducted between 2013 and 2014, citing that the pair failed to “film patient examinations in full, did not appropriately show details of their analyses in the papers and made false statements,” and in not doing so, had failed in the protective responsibility incumbent upon scientists when involving serious ill study participants. (Those charges did not end up preventing Nature Communications from publishing the latest study; the journal did not respond to requests for comment.)
Still, the potential behind BCI technologies is nothing to scoff at. The new findings are another example of how BCI implants can help restore function and improve the quality of life not just for ALS patients, but also those suffering from other neurological disorders that affect muscles, like cerebral palsy, stroke, or spinal cord injury.
With the latest findings based solely on a single patient followed over two years, the researchers are eager to test out their approach in a much larger trial featuring ALS patients who may be in more advanced stages of the disease—especially since the number of people living with ALS is expected to rise from around 223,0000 in 2015 to over 376,000 by 2040. BCI research may provide CLIS patients with a renewed lease on life.
