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Spinal cord injury, stroke and amyotrophic lateral sclerosis (ALS) are all conditions that can disrupt the critical nervous system pathways responsible for controlling muscles. This frequently leads to a profound loss of motor function, such as weakness or paralysis.
Elon Musk’s Neuralink has developed a wireless brain-computer interface (BCI) for those whose minds are intact, but they have lost the ability to control movement due to injury or disease. With this surgical procedure, patients can now move a computer cursor or type on a keyboard with their thoughts.
The device, called Telepathy, is inserted into the part of the motor cortex that controls hand and arm movements, which is located in the frontal lobe (the top middle part of the brain). According to an online interview with Dr. Matthew MacDougall, Head of Surgery at Neuralink, the surgery begins by creating a small opening in the skull above the motor cortex. This is done by the surgeon. Subsequently, a robotic arm uses micron-level precision to insert the flexible, ultra-thin threads that contain the electrodes, avoiding surface blood vessels. The surgical team supervises and confirms electrode placement using specialized software. Once implanted, the surgeon screws the skull back on and sews the skin back together.
How it works
The microelectrodes will detect and transmit neuronal signals wirelessly to external software, which then decodes the signal into behaviour by measuring how often action potential spikes fire within a specific window of time (frequency characteristics of neural firing patterns). Through a calibration process, the model learns each user’s intended movements. Initially, patients usually imagine moving their hand across the screen to move a cursor, let’s say from left to right and up and down. Once enough calibration data is in the model, control becomes automatic without much thought required, allowing near-instant movement to match natural intention.
Neuralink’s success
It is important to note that Neuralink’s technology builds upon previously existing frameworks and decades’ worth of research by others, laying the groundwork. In 1988, Dr. Georgopoulos and colleagues showed that they could decipher movement intent from neural signals. Later, Dr. Hochberg, a neurologist in Massachusetts who currently leads the BrainGate collaboration, used what is called the Utah Array (a rigid bed of metal microelectrodes that are inserted into the brain by a surgeon’s hand) to record and decode brain motor neurons communicating with external devices such as a cursor or prosthetic arm. Due to the inflexibility of a small square of electrodes being inserted in this manner, it damaged blood vessels it encountered, causing scar tissue build-up, a decline in signal, and an immune response. Further, their system originally used wired connections between the implant and external computers to decode the signals, requiring a continuous open socket in the skull.
Neuralink recognized a need for fundamental design changes, which resulted in the incorporation of wireless Bluetooth technology, as well as flexible and smaller electrodes that can be inserted individually to avoid scar tissue, making the BCI more usable on a daily basis. In fact, the threads containing the electrodes are thinner than human hair. Further, the Bluetooth-enabled electrode showed long-term stability in an animal model study in 2019, leading to FDA approval of a clinical trial called the PRIME Study – short for Precise Robotically Implanted Brain-Computer Interface – in 2023. BrainGate also recognized the need for wireless technology and, based on years of their own animal research, had conducted a clinical trial using it, published in 2021.
Vision for the future
In the future, the Neuralink team sees itself restoring vision and navigation capabilities to individuals with blindness using Blindsight, which stimulates specific firing patterns in the visual cortex to create a visual image that matches what they would be seeing in front of them. The FDA granted Blindsight breakthrough device designation in 2024 after successful pre-clinical trials in non-human primates. However, again, Neuralink stands on the shoulders of research done at least as far back as 1968, where Brindley and Lewin evoked visual sensations in a blind patient.
According to a Neuralink 2025 update, its upcoming Deep device aims to stimulate deeper layers of the brain, such as the limbic system, to help people suffering from neuropathic pain, psychiatric conditions, tinnitus and epilepsy.
Neuralink has expanded its clinical trials to the United Kingdom, United Arab Emirates and Canada. Canada has initiated the first international clinical trial, called the CAN-PRIME study, at the University Health Network’s Toronto Western Hospital, for two patients with spinal cord injury. Taking place on August 27 and September 3, 2025, the surgeries were part of the next frontier in care for patients with limited options.
Where are we with regenerative medicine approaches?
Musk’s technology does not regenerate neurons or slow down ALS. However, it allows patients to send an accurate email and even continue certain types of work. This progress allows them to earn income, play video games with friends and family, or read online books by flipping through digital pages with their mind, which restores independence for those with movement disorders. The technology will further be developed to include the use of prosthetic arms or fully external human-shaped robots that can respond to thought commands, helping people grab items or feed themselves.
Although Neuralink doesn’t regenerate neurons, electrode implantation used in other ways presents new opportunities for regeneration and neuroplasticity. In a small Phase I clinical trial led by investigators at Weill Cornell Medicine, Stanford University, the Cleveland Clinic, Harvard Medical School and the University of Utah, traumatic brain injury patients showed marked cognitive improvement after deep brain stimulation of the thalamus, after three months of treatment. In this study, even 3-18 years post-injury, participants regained attention, working memory and information-processing speed. Though the mechanism remains unclear, stimulation of the healthy thalamic neurons could be enhancing neuroplasticity throughout thalamic connections, restoring some neural connectivity across the brain. In addition, in a previous post I talked about how biodegradable electrodes can stimulate endogenous repair through neuron proliferation and migration in animal models of stroke.
In Canada, important progress is being made in this field. Pay attention to the work of Freda Miller, University of British Columbia, Andras Nagy, Mount Sinai Hospital, Benjamin Lindsey, University of Manitoba, Anastassia Voronova, University of Alberta, and others, and appreciate the funding support coming from the Stem Cell Network, Brain Canada, Medicine by Design, the Canadian Institutes of Health Research, and other funding groups.
Final thoughts
One of the criticisms Neuralink has received is their lack of published papers regarding clinical data, and how it obtains consent from patients, device stability, and infection rates. Further, Musk, the developer of Neuralink, has spoken about his sci-fi ambitions, which include the ability to Matrix-style download information or telepathically communicate with people without a disability, raising ethical concerns.
Neuralink is not the only company working on large advancements allowing people to control a cursor with their minds. Neuralink’s main competitors include BrainGate, Utah-based Blackrock Neurotech, Texas-based Paradromics, which originated at Stanford University, and New York-based Synchron, which originated in Australia. All have achieved promising clinical outcomes in BCI research, so there are a lot of exciting new advancements to follow going forward!
A total of 12 patients worldwide have received the Neuralink device so far. Weeks after the very first patient, Noland Arbaugh, received his procedure due to spinal cord injury, many of the device’s threads retracted from his brain. Instead of redoing the surgery, engineers got to work recalibrating the recording algorithm to be more sensitive to neural signals and improved the translation of these signals into cursor movements so that Noland could perform most tasks he had been able to do before. At least Neuralink worked promptly to implement measures to mitigate the risk of thread retraction in future patients. They did this by reducing brain motion during the surgery and reducing the gap between the implant and the surface of the brain.
Finally, several articles, such as this one from The Independent, reported that DJ Seo, the co-founder of Neuralink, revealed that a whopping 10,000 patients are already interested in the brain implant after the worldwide Patient Registry list opened earlier this year. This indicates the implant might be of widespread use very soon and that Neuralink is leading a large technological shift that society may not be ready for, especially since Musk hopes to expand the use of the implant to those without disabilities who want upgrades, creating a possible “neuro-elite” class.
Despite the ethical implications, it will be nice to see lasting benefits from the procedure for those with disabilities for many years to come.
Krystal Jacques
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