Two ALS patients in Australia have been able to control their PCs through direct thought with the implant of a brain-computer interface from Synchron, a biomed startup based in San Francisco.
The interface—a kind of sensor called Stentrode--allowed the patients with severe paralysis to resume tasks such as texting, emailing, and online shopping and banking through direct thought. The small and flexible interface was implanted via the jugular vein without the need for open brain surgery.
“This is a breakthrough moment for the field of brain-computer interfaces,” said Synchron CEO Thomas Oxley. “Stentrode will one day be able to help millions of people with paralysis.”
The patients used Stentrode to control the Windows 10 OS when combined with an eye tracker for cursor navigation without a mouse. They undertook machine learning-assisted training to control various mouse click motions. Their click accuracy was up to 93% and typing speeds reached as high as 20 characters a minute without the use of predictive text. They reached the level of unsupervised home use in as little as 71 days.
Stentrode has the ability to pick up specific electrical frequencies emitted by the brain at the motor cortex, which controls movement, and transmit them to the PC via a wireless device implanted in the chest. A brain-controlled hands-free app platform also translates brain impulses into standard digital language.
Graham Felstead, 75, the first patient enrolled in the Stentrode study, said in a statement that the device “has allowed me to be productive again, including shopping and banking. It’s incredible to gain this level of independence back.” He has severe paralysis due to ALS and received his implant more than a year ago, in August 2019.
The second patient, Philip O’Keefe, 60, has been able to conduct work-related tasks after receiving the implant in April 2020. He lives and works part time at home with his wife and two children.
Synchron believes that entry of the Stentrode device through the blood vessels may reduce the risk of brain tissue inflammation and rejection of the device, which has been a concern for other surgical techniques involving direct brain penetration.
Synchron’s work is still in its early stages. Stentrode received Breakthrough Device designation in late August from the U.S. FDA. The data from the current study will be used in finalizing protocols for a future FDA-approved trial that could lead to U.S. marketing approval.
The market for brain-computer interfaces has the potential to be a $2 billion industry, Synchron said. Future potential applications of Stentrode include treating nervous system conditions such as Parkinson’s disease, epilepsy, depression and hypertension.
Neuralink Corp., an Elon Musk company, and Paradromics are among a group of companies that are building technology to record brain signals. Stanford University researchers have said they can decode brain activity related to handwriting by a patient whose hand was paralyzed.
The U.S. Defense Advanced Research Projects Agency has also funded research allowing quadriplegics to move robot arms and the Pentagon has backed technology using light instead of embedded electrodes to gather brain signals.