Synchron demonstrates results of receiving Stentrod brain-computer implant

Two ALS patients in Australia have been able to control their computers simply by thinking about them, using a brain-computer interface developed by Synchron, a San Francisco-based biomedical startup.

The findings were published last week in the Journal of Neurointerventional Surgery and summarized in a news release on the Synchron website.

George Felstead (pictured with his wife Nancy), recipient of the world's first vascular implantable neural interface device, the "Stentrode," has been able to type and shop online through a chest implant that collects and wirelessly transmits brain signals to a personal computer. The flexible brain sensor is made by Synchron, a San Francisco startup.

The interface uses a sensor called a Stentrode, which allows severely paralyzed patients to resume tasks such as texting, emailing, online shopping and banking by simply thinking about it. The small and flexible interface is implanted through the jugular vein, eliminating the need for open brain surgery.

“This is a breakthrough moment in the field of brain-computer interfaces,” said Thomas Oxley, CEO of Synchron. “The Stentrode could one day help millions of people with paralysis.”

The patients used the Stentrode to control the Windows 10 operating system, while using an eye tracker for cursor navigation instead of a mouse. They underwent machine learning-assisted training to control various mouse click actions. They achieved a click accuracy of 93% and a typing speed of up to 20 characters per minute. They were able to reach the level of unsupervised home use in just 71 days.

The Stentrode picks up specific electrical frequencies emitted by the brain in the cortex that controls movement and transmits them to a PC via a wireless device implanted in the chest. A brain-controlled app platform also converts the brain's impulses into a standard digital language.

Graham Felstead, 75, the first patient to take part in the Stentrode trial, said in a statement that the device “has allowed me to be productive again, including shopping and banking.” He has severe paralysis caused by ALS and received the implant more than a year ago, in August 2019.

The second patient, Philip O'Keefe, 60, received the implant in April 2020 and has been able to perform work-related tasks. He lives and works from home with his wife and two children.

Synchron believes that passing the stent device through a blood vessel could reduce the risk of brain tissue inflammation and rejection, which is a concern with other surgical techniques that involve direct brain penetration.

Synchron's work is still in the early stages. Stentrode received Breakthrough Device certification from the U.S. FDA in late August. Data from the current study will be used to finalize a trial protocol for future FDA approval, which could lead to U.S. market approval.

The brain-computer interface market has the potential to become a $2 billion industry, Synchron said. Potential future applications include treating neurological disorders such as Parkinson's, epilepsy, depression and high blood pressure.

Elon Musk's Neuralink and Paradromics are also developing brain-computer interfaces, and researchers at Stanford University say they can program the brain activity associated with writing in a patient with paralyzed hands.

DARPA is also funding research into mobile robots that assist quadriplegics, using technology that uses light rather than embedded electrodes to collect brain signals.