The first brain-computer interface device was implanted in a patient in the US earlier in July by a doctor at the medical center, Mount Sinai West, in New York, in an investigatory trial of Synchron’s procedure to help patients suffering from ALS (amyotrophic lateral sclerosis) text by thinking.
The procedure involved the doctor threading a 1.5-inch-long implant comprised of wires and electrodes into a blood vessel in the brain of a patient with ALS. The hope is that the patient, who’s lost the ability to move and speak, will be able to surf the web and communicate via email and text simply by thinking, and the device will translate the patient’s thoughts into commands sent to a computer.
Synchron, the startup behind the technology, has already implanted its devices in four patients in Australia, who haven’t experienced side effects and have been able to carry out such tasks as sending WhatsApp messages and making online purchases.
The implant was a major step forward in a nascent industry, putting the Brooklyn-based company ahead of competitors, including ahead of Elon Musk’s Neuralink Corp.
Dr. Shahram Majidi, the neurointerventional surgeon who performed the procedure said, “This surgery was special because of its implications and huge potential.” This was the first procedure the company has performed in the US.
Fascinated by the brain-computer interface implant
The brain-computer interface (BCI) has caught the attention of many in the technological field because its device, known as the stentrode, can be inserted into the brain without cutting through a person’s skull or damaging tissue.
A doctor makes an incision in the patient’s neck and feeds the stentrode via a catheter through the jugular vein into a blood vessel nestled within the motor cortex.
As the catheter is removed, the stentrode, a cylindrical, hollow wire mesh opens up and begins to fuse with the outer edges of the vessel. According to Majidi, the process is very similar to implanting a coronary stent and takes only a few minutes.
A second procedure then connects the stentrode via a wire to a computing device implanted in the patient’s chest. To do this, the surgeon must create a tunnel for the wire and a pocket for the device underneath the patient’s skin much like what’s done to accommodate a pacemaker.
The stentrode reads the signals when neurons fire in the brain, and the computing device amplifies those signals and sends them out to a computer or smartphone via Bluetooth.
The stentrode then uses sixteen electrodes to monitor brain activity and record the firing of neurons when a person thinks. The signal strength improves over time as the device fuses deeper into the blood vessel and gets closer to the neurons. Software is used to analyze the patterns of brain data and match them with the the user’s goal.
Although this may make some people squeamish, it’s far less invasive than the current state-of-the-art technology, known as the Utah array, which requires doctors to make incisions in the scalp and drill into the skull to place rigid needles in the brain. Those then attach to a lime-size device placed on top of a person’s head.
The Utah array has allowed patients with severe disabilities to do remarkable things, such as command robotic arms to bring them a cup of water. However, they generally use the devices only under supervision at a hospital, and the brain tends to form scar tissue around it, degrading the signals gathered by the electronics over time.
Synchron’s brain-computer interface still on trial in US
There are more cautious policies around these types of procedures in the US than in Australia, and it took years of work for Synchron to receive a go-ahead from the Food and Drug Administration.
The technology remains in its early stages of development, and the trial is meant to focus more on how the human body reacts to the implant and how clear the brain signals are than on the functions a person can perform with the device.
The US patient is the first in a six-person, $10 million trial funded by the National Institutes of Health and led by Douglas Weber, a professor of mechanical engineering at Carnegie Mellon University, and David Putrino, the director of rehabilitation innovation at Mount Sinai.
People in the BCI field have a long history of hyping up technologies that end up with limitations preventing broad use. In light of this, the US patient requested anonymity and declined to discuss the operation so as not to promote the Synchron device before experiencing its pros and cons.
The limited computing power of the stentrode means the device can’t translate whole sentences. Rather, a patient with the implant picks letters one-by-one on a screen, and the technology converts those “yes or no” thoughts into commands.
Doctors and researchers believe Synchron’s technology could lead to major advances in the way people with severe disabilities go about their day-to-day lives. Unlike people with Utah arrays, Synchron’s Australian patients are using the devices in their own homes.
David Putrino says, “One of the untold secrets of the brain-implant technologies trialed over the past two decades is that they have never, once, really translated into independent home use.”
Dr. Tom Oxley, Synchron’s co-founder and chief executive officer, hopes to implant as many as sixteen stentrodes in the coming year, as his company looks to move beyond the NIH study and advance trials for review by the FDA.
Oxley hopes this first US procedure will show that the operation is so similar to existing surgeries around stents and pacemakers that it can be performed on a regular basis by thousands of doctors. “I feel like we have broken through this barrier and that people get it,” he says.
In the months and years ahead, Synchron aims to shrink the size of its devices while increasing their computing power. If it’s successful, the company would be able to place numerous stentrodes in each patient in different parts of the brain, allowing them to perform more functions.