Jacking into the cortex: The promising future of brain-computer interfaces

It was a video that made headlines around the world: in May 2023, a 40-year-old Dutch man named Gert-Jan Oskam, who had been paralysed after a cycling accident twelve years earlier, was able to walk again by just thinking about it. "I feel like a toddler, learning to walk again”, Oskam told the BBC. The secret behind his sudden newfound mobility is a brain implant that works in conjunction with a spinal cord stimulator made by the start-up Onward Medical, a spin-off from the École Polytechnique Fédérale de Lausanne (EPFL).

Brain-computer interfaces (BCIs): a leap forward
But that isn’t the only milestone reached this year in the quest to help patients suffering from debilitating diseases such as spinal cord injury, stroke and amyotrophic lateral sclerosis (ALS). For brain-computer interfaces, a technology that scientists have been studying for decades, 2023 has proven to be a momentous year.

In New York, a quadriplegic patient underwent a successful double neural bypass linking his brain, spinal cord and body, and enabling him to lift his arms and regain his sense of touch. In Sweden, scientists reported that a 50-year-old woman who had lost her hand was fitted with a bionic hand that is electronically connected to her brain, giving her the ability to manipulate objects. And in Australia, a group of four men suffering from ALS-induced paralysis were outfitted with a brain implant that collects signals from the motor cortex and translates them in a way that enables them to communicate using their thoughts.

Brain-computer interfaces (BCIs) open up new avenues

While researchers are pursuing different approaches to invasive implants, they agree that what was once confined to the lab is on its way to the broader population. Brain-computer interfaces (BCIs) open up new avenues for giving severely disabled patients the ability to move and speak, and have the potential to enhance the lives of the world’s rapidly ageing population as they deal with ailments such as unsteady gait, tremors and Parkinson’s disease or depression.
“We’ve been trying to figure out what the brain does as the control centre for the body for the last 30 years, whether it’s sensory, motor translation, or thoughts and emotions”, says Kurt Haggstrom, Chief Commercial Officer at the Brooklyn-based Brain-Computer-Interface (BCI) start-up Synchron. The time has come, he adds, to translate academic insights into neuroprosthetics, or hardware and software that help individuals be more independent and autonomous. “This isn’t really ten, 20 or 30 years out. It’s happening today, although we start with a small number of patients”, Haggstrom says.
Synchron, founded in 2012, is behind the clinical trial in Australia, and has since signed up another six patients, this time in the US, to be implanted with its technology. Synchron stands out in this increasingly crowded field because it has received approval from the American medical watchdog, the FDA, to start clinical trials with humans. Also, tech billionaires Jeff Bezos and Bill Gates have both provided funding, raising its profile against Neuralink, a competitor backed by Elon Musk. 
 

Coordinated brain-computer-interface research in Europe
Scientists define brain-computer interfaces as technology that measures central nervous system (CNS) activity and converts it into artificial output. The Brain/Neural Computer Interaction Horizon 2020 project, an initiative of the European Commission for coordinating brain-computer-interface research, has identified six areas of application, namely to replace, restore, enhance, supplement, or improve natural CNS output and to further investigate CNS function.

Which hard or software is ultimately used to help BCI users walk or talk again varies and does not always involve opening the skull. From deep-brain stimulation to less aggressive transcranial stimulation from the outside, companies are exploring a wide range of options. Some, such as Utah-based Blackrock Microsystems, have been supplying their implants to labs and clinics around the world for years.

Deep brain stimulation
The deeper you jack into the brain, though, the bigger the risk and the more uncertain the outcome. Musk’s Neuralink, for instance, has so far only experimented with inserting electrodes into the brains of primates, and plans to follow up with the first human trials next year using a surgical robot. The company attracted significant criticism for the first animal trials.

Competitor Synchron has developed a less invasive method that works similar to a cardiovascular stent. Surgeons use a catheter to place a so-called stentrode underneath the brain’s motor cortex. It collects signals and sends them to a device under the patient’s skin in the chest area, which in turn communicates with external devices via Bluetooth. Surgery takes only a few hours and patients can go home the same day.  

Reanimating dormant neurons

Swiss researchers at the EPFL’s NeuroRestore group run by neuroscientists Grégoire Courtine and Jocelyne Bloch are focusing on reanimating dormant spinal cords, using both a spinal cord stimulator plus a brain-spinal cord interface. The latter records motor intentions in the brain and then translates them into spinal cord signals that eventually promote the intended movement. As co-founders of Onward Medical, the duo’s research laid the groundwork that enabled Gert-Jan Oskar to walk again. “The implant we have was developed by a neurosurgeon, so it’s very practical, robust and easy to place”, explains Bloch.

NeuroRestore is currently looking into applying brain-computer-interface technology for other debilitating ailments such as strokes and Parkinson’s disease, says Grégoire Courtine. It reported in November that a 63-year-old Parkinson’s patient with severely impaired gait was able to walk 6 km after receiving an experimental spinal implant. But Courtine tempers expectations: “There’s a long way to go. We are at the stage of clinical studies. As a commercial device, it will not happen before the end of the decade.”

Understanding of neurological functions has improved dramtically

Nevertheless, medical practitioners are watching the space with guarded excitement. “Our understanding of neurological functions has improved dramatically over the years, as have software and hardware solutions. None of these strategies cure or heal the disease condition, but they ease symptoms by partially restoring neurological functions, which leads to improved quality of life”, says Dr. Norbert Weidner, medical director of the Spinal Cord Injury Center at Heidelberg University Hospital.

He points out that anything that is implanted directly into the brain or spinal cord is likely to cause foreign body reactions which limit long-term stability and function. Not to mention the psychological impact on patients who suddenly regain long-lost capabilities and have to live with the prospect of potentially losing them again should the system not work properly.

Ethical issues to be addressed
Besides the medical challenges, however, recording and translating human brain activity also comes with as yet undefined privacy concerns. UNESCO, for instance, in July raised the alarm that rapid advances in brain implants and scans combined with artificial intelligence pose a threat to “mental privacy”.
Gabriela Ramos, Assistant Director-General for Social and Human Sciences at Unesco, warned that "we are on a path to a world in which algorithms will enable us to decode people's mental processes and directly manipulate the brain mechanisms underlying their intentions, emotions and decisions.”

Brain-computer interfaces market expected to quadruple
Even though a lot of unknowns remain, market researchers foresee a multi-billion-dollar market for Brain-Computer-Interface systems. Precedence Research recently reported that for 2023, the BCI market is estimated to be 2.35 billion US dollars. And by 2023, it expects the market to roughly quadruple in size to 9.44 billion US dollars, pointing to the growing number of geriatric patients as a likely key driver for growth.