Tag: braingate

  • Can Brain-Computer Interfaces Restore Movement After Paralysis? The Current Evidence

    There is a man with ALS who has been using a brain-computer interface at home, independently, for over two years. Four microelectrode arrays sit in his left motor cortex, recording from 256 electrodes. He uses the system to control his personal computer—typing, browsing, communicating—through a multimodal BCI that decodes both his attempted speech into text and his attempted hand movements into cursor movements and clicks. In structured tests, the system is 99 percent accurate at outputting his intended words. Over 4,800 hours of use, he has communicated more than 237,000 sentences at roughly 56 words per minute. He works full-time.

    That’s not a laboratory demonstration. That’s not a press release. That’s a BrainGate2 clinical trial participant living his life with a brain-computer interface, reported at Neuroscience 2025 and representing the most sustained, independent, real-world use of a speech and movement BCI ever documented. And it’s one data point in a field that, after two decades of incremental academic progress, is now moving fast enough that the clinical evidence is outpacing most people’s mental model of what’s possible.

    So: can BCIs restore movement after paralysis? The honest answer requires separating three very different things that get conflated in headlines—restored communication (controlling a cursor or generating speech), restored functional movement (moving a paralyzed limb), and restored independent mobility (walking). The evidence is strongest for the first, genuinely promising for the second, and early but real for the third.

    Communication: the problem that’s closest to solved

    The clearest clinical wins in BCI right now are in restoring communication for people who’ve lost the ability to speak or type. This is where BrainGate has the deepest data.

    A March 2026 study published in Nature Neuroscience demonstrated that two BrainGate participants—one with ALS, one with a cervical spinal cord injury—could type on a standard QWERTY keyboard layout by attempting finger movements. Not imagined cursor movements. Not an abstract mental task. Actual attempted typing—the participants thought about pressing specific keys with specific fingers, the implanted microelectrode arrays recorded the neural patterns associated with each attempted movement, and a decoder translated those patterns into keystrokes in real time. The system achieved speeds approaching 90 characters per minute, which is in the range of normal phone typing for a non-disabled person.

    A separate BrainGate participant at UC Davis achieved 97 percent accuracy on a speech BCI that translates attempted speech into text—the most accurate speech neuroprosthesis ever reported, published in the New England Journal of Medicine. The system reconstructed the patient’s voice from pre-disease recordings, so the synthesized output sounds like him, not like a generic computer voice. That distinction matters more than the engineering might suggest—hearing your own voice come back to you after disease has taken it is not a technical specification, it’s a human experience.

    Neuralink’s participants have demonstrated cursor control, web browsing, and social media use through the N1 implant, with 21 patients now enrolled globally. Synchron’s endovascular BCI—threaded through the jugular vein, no craniotomy required—has enabled an ALS patient to control an iPad, an Apple Vision Pro, and Amazon Alexa using thought alone, all through native accessibility protocols on consumer devices. These are real outcomes in real patients. The communication problem for severe paralysis is not solved, but the clinical evidence now clearly demonstrates that implanted BCIs can restore functional digital communication at speeds that make them practical for daily life.

    Functional movement: the harder problem

    Restoring communication means decoding neural signals and routing them to a computer. Restoring movement means decoding neural signals and routing them back into the body—either to a robotic limb, a functional electrical stimulation system, or a spinal cord stimulator that reactivates the patient’s own muscles below the injury. The decoding part is the same. The output part is enormously more complex.

    BrainGate participants have controlled robotic arms using neural signals since the early 2010s—the 2012 demonstration where a woman with tetraplegia used a BCI-controlled robotic arm to drink coffee from a bottle was a watershed moment in the field. Nathan Copeland, implanted in 2015, used a BCI-controlled robotic arm to fist-bump President Obama in 2016 and later demonstrated bidirectional BCI capability—not just controlling the arm with his brain, but receiving tactile sensation feedback through intracortical microstimulation of his somatosensory cortex. He could feel when the robotic hand touched an object. That sensory feedback loop—reaching, grasping, and feeling what you’ve grasped—is where BCIs start to approximate actual limb function rather than just cursor control applied to a mechanical arm.

    A landmark Neuroscience 2025 report provided the most extensive human safety data ever published on intracortical microstimulation for artificial touch. Five participants received millions of electrical stimulation pulses to their somatosensory cortex over a combined 24 participant-years. The stimulation evoked stable, high-quality tactile sensations in the hand without serious adverse effects. More than half the electrodes continued functioning reliably even after a decade of implantation in one participant. That’s the kind of long-duration safety data the field has needed—demonstrating that you can stimulate the brain to create artificial sensation chronically, over years, without breaking things.

    The most dramatic functional movement results, however, are coming not from BCIs alone but from the combination of BCIs with spinal cord stimulation—and this is where the story gets genuinely exciting.

    Spinal cord stimulation: the other half of the equation

    ONWARD Medical’s ARC-EX system received FDA clearance in December 2024—the first non-invasive spinal cord stimulation device cleared for spinal cord injury. The system places electrodes on the skin at the back of the neck and delivers programmed electrical stimulation to the cervical spinal cord. In the pivotal Up-LIFT trial, published in Nature Medicine, 90 percent of participants with chronic incomplete tetraplegia showed improved upper-limb strength or function. Eighty-seven percent reported improved quality of life. Four participants demonstrated changes in their neurological level of injury, and three improved their AIS (American Spinal Injury Association Impairment Scale) classification—including one participant who moved from complete to incomplete spinal cord injury. That last detail is worth pausing on: a person classified as having a complete injury—no motor or sensory function below the level of the lesion—regained measurable function.

    ONWARD’s implantable system, ARC-IM, goes further. Epidural leads are placed directly on the spinal cord and deliver targeted stimulation that can restore stepping movements in people with complete paraplegia. The research, led by Grégoire Courtine and Jocelyne Bloch at EPFL and Lausanne University Hospital, has produced videos that are almost surreal to watch—people who have been told they will never walk again, standing up and taking steps with epidural stimulation active. A 2025 paper in Science Translational Medicine demonstrated that high-frequency epidural stimulation reduced spasticity and facilitated walking recovery in patients with spinal cord injury, establishing another mechanism by which electrical stimulation of the spinal cord can restore function that was thought to be permanently lost.

    The next logical step—and ONWARD is actively developing this—is pairing spinal cord stimulation with a brain-computer interface. The ARC-BCI system would use a cortical implant to decode the patient’s intended movements, then route those decoded intentions to the spinal cord stimulator, which would activate the appropriate muscles in the correct sequence to produce natural-feeling movement. Brain thinks “step forward.” Decoder translates the intention. Stimulator activates the leg muscles. The patient walks. Not with a robotic exoskeleton strapped to the outside of their body, but with their own legs, driven by their own neural intentions, bridged across the injury by electronics.

    This hasn’t been demonstrated in a full clinical trial yet. It’s in feasibility studies. But every component has been individually validated in humans: the cortical decoder works, the spinal cord stimulator works, and the closed-loop integration is an engineering challenge, not a science challenge. The gap between “each piece works separately” and “the integrated system works reliably in daily life” is real—and it’s the kind of gap that takes years to close—but it’s a gap measured in engineering iterations, not fundamental breakthroughs.

    What “restored movement” actually looks like in practice

    Here’s the part that gets lost in the headlines. When a BCI study reports “restored movement,” the movement being restored is typically not what a healthy person would recognize as normal motor function. A BCI-controlled robotic arm reaches more slowly, grasps less precisely, and fatigues faster (in terms of signal quality, not muscle fatigue) than a biological arm. Spinal-cord-stimulation-assisted walking involves extensive preparation, careful calibration, and a level of concentration from the patient that makes it exhausting rather than automatic. These are real functional gains—the difference between being able to grasp a cup and not being able to grasp a cup is enormous when you’re the person holding the cup—but they’re not the seamless restoration of pre-injury function that the promotional materials sometimes imply.

    The trajectory matters more than the current state. The BrainGate participant typing at 90 characters per minute in 2026 is operating a system that typed at roughly 15 characters per minute a decade ago. The speech BCI achieving 97 percent accuracy in 2025 is operating a system that achieved roughly 70 percent accuracy five years earlier. The decoders are getting better because the AI is getting better, the electrode technology is improving, and the cumulative participant-hours of data are feeding algorithms that learn to interpret neural patterns with increasing precision. The slope of this curve matters as much as the current position on it.

    The honest timeline

    BCIs that restore functional communication for people with severe paralysis will be commercially available medical devices within three to five years—probably led by Synchron’s endovascular approach or a Neuralink-derived product, with BrainGate’s academic work continuing to push the frontier of what’s decodable. BCIs that restore basic upper-limb movement—grasp, reach, manipulation—through robotic arms or functional electrical stimulation are probably five to ten years from routine clinical use. Integrated BCI-plus-spinal-cord-stimulation systems that restore walking for people with paraplegia are further out—likely a decade or more from anything resembling standard clinical practice—but the foundational work is human-validated and advancing.

    None of this is speculation. It’s extrapolation from clinical data that exists, published in Nature, Nature Neuroscience, the New England Journal of Medicine, and Science Translational Medicine. The field has moved past proof of concept and into the phase where the questions are about reliability, scalability, durability, and insurance coverage—which are the boring questions that mean the technology is real.

    We cover the full landscape of brain-computer interfaces and neuroprosthetics—from the earliest experiments to every company and approach described above—across 48 lectures in our Neuroprosthetics & Brain-Computer Interfaces course. If the BrainGate typing data or the spinal cord stimulation results changed what you thought was possible, the course goes considerably deeper.

  • Brain-Computer Interfaces in 2026: Where the Technology Actually Stands

    When I read headlines about brain-computer interfaces—and there’s a new one roughly every 72 hours, each seemingly announcing that the future has arrived—I’m reading them with the same part of my brain that reads MRI reports and discharge summaries. I’m looking for the mechanism, the sample size, the follow-up period, and the part of the press release that got quietly omitted. And what I keep finding is a field where the actual science is genuinely remarkable, the engineering is legitimately impressive, and the gap between what’s been demonstrated and what’s being promised is roughly the width of the Grand Canyon.

    So here’s where brain-computer interfaces actually stand in March 2026. Not the press release version. Not the “we’re five years from The Matrix” version. The clinical reality, company by company, with the caveats attached.

    What a BCI actually does (the 30-second version)

    Your motor cortex generates electrical signals when you intend to move. In a healthy nervous system, those signals travel down your spinal cord, through peripheral nerves, and to your muscles. In someone with a spinal cord injury or ALS, the signals still fire at the top—the brain is still doing its job—but the wiring downstream is broken. A brain-computer interface picks up those electrical signals directly from the cortex and routes them to an external device instead of to muscles. You think about moving your hand, the electrodes record the neural activity, a decoder translates it into a digital command, and a cursor moves on a screen or a robotic arm reaches for a cup. That’s it. That’s the core mechanism. Everything else is engineering.

    The engineering, of course, is where it gets complicated—and where the companies diverge in ways that matter enormously for which patients actually benefit, when, and at what risk.

    Neuralink: The one you’ve heard of

    Neuralink gets roughly 95% of the media coverage in this space despite being neither the first nor the furthest along clinically. What they have is Elon Musk, which in the attention economy is worth more than a decade of peer-reviewed publications. The N1 implant is a coin-sized device with 1,024 electrodes distributed across 64 ultra-thin polymer threads, inserted into the motor cortex by a custom surgical robot. The threads are thinner than a human hair—about 5 microns—and that’s genuinely impressive from a materials science standpoint. The pitch is high electrode count plus wireless transmission plus a cosmetically invisible implant that sits flush with the skull.

    As of early 2026, Neuralink has 21 participants enrolled in its global clinical trials, up from 12 in September 2025. The first patient, Noland Arbaugh—quadriplegic from a diving accident—demonstrated the ability to control a cursor, play video games, browse the internet, and post on social media using the implant. The third patient, Brad Smith, who has ALS and is ventilator-dependent, can type using the device. These are real outcomes. They matter. A person who cannot move anything below the neck using thought alone to navigate a computer is not a small thing.

    But—and this is where my press release detector starts going off—Musk announced on December 31, 2025, that Neuralink would begin “high-volume production” of BCI devices and move to “almost entirely automated surgical procedures” in 2026. He also announced the Blindsight implant for restoring vision in the blind would begin its first patient trial this year. If you’ve followed Musk’s timeline promises across any of his companies—Tesla Full Self-Driving, the Cybertruck, the Boring Company’s Vegas Loop—you know that announced timelines and delivered timelines have a relationship best described as aspirational. “High-volume production” in 2026 from a company with 21 trial participants is a claim that requires a lot of intermediate steps that haven’t been publicly demonstrated: manufacturing consistency, surgical standardization, long-term safety data, and FDA clearance for anything beyond an investigational device. None of those things have happened yet.

    The first patient also had a documented issue: some electrode threads retracted from the cortex after implantation, reducing the number of functional electrodes. Neuralink adjusted its approach for subsequent patients, but this is exactly the kind of biocompatibility challenge that doesn’t show up in the demo reel. Brain tissue is not a circuit board. It’s alive, it moves, it forms scar tissue around foreign objects, and it does not appreciate being punctured by 64 threads, no matter how thin they are.

    Synchron: The one that doesn’t require brain surgery

    Synchron is doing something fundamentally different, and I think the approach deserves more attention than it gets. Their Stentrode device is an endovascular BCI—it’s threaded up through the jugular vein and deployed inside a blood vessel on the surface of the motor cortex, using the same catheter techniques that interventional neurologists (my people) use every day to treat strokes and aneurysms. No craniotomy. No opening the skull. No penetrating brain tissue. The median procedure time in their COMMAND trial was 20 minutes.

    The tradeoff is resolution. The Stentrode has 16 electrodes compared to Neuralink’s 1,024. It’s sitting inside a blood vessel, not directly in cortical tissue, so the signals it picks up are less granular—think of it as the difference between sitting in the front row at a concert versus listening from the parking lot. You can still hear the music, but you’re not picking up the individual instruments. For the current application—point-and-click cursor control, typing, navigating apps—that’s sufficient. An ALS patient in their trial became the first person to control an iPad with a BCI, using Apple’s native Switch Control accessibility feature. He later connected to an Apple Vision Pro and Amazon Alexa using only his thoughts. These are consumer devices, unmodified, working with a brain implant through standard accessibility protocols. That’s a very different value proposition than a research demo in a lab.

    Synchron’s COMMAND trial—six patients, 12-month follow-up—met its primary safety endpoint with no device-related serious adverse events to the brain or vasculature. They raised $200 million in Series D funding in late 2025, backed by Bezos, Gates, and the Qatar Investment Authority, and are preparing pivotal trials for 2026 ahead of commercial approval. They’ve also announced a next-generation whole-brain interface with significantly higher channel counts, though details won’t arrive until later this year.

    The strategic bet Synchron is making is that a lower-resolution device implanted through an existing, well-understood medical procedure will reach more patients faster than a higher-resolution device that requires brain surgery. From a regulatory and clinical adoption standpoint, that bet has a lot of logic behind it. Interventional neuroradiologists already know how to navigate catheters through cerebral vasculature. The training curve is short. The risk profile maps onto procedures we’ve been doing for decades.

    BrainGate and Blackrock Neurotech: The ones that were here first

    The BrainGate consortium—a collaboration across Mass General Brigham, Brown University, Stanford, and several other institutions—has been running clinical trials of implantable BCIs since 2004, which is two decades before Neuralink implanted its first patient. Their technology is built on Blackrock Neurotech’s Utah Array, a grid of 96 silicon microelectrodes that penetrates the cortex. It’s the workhorse of the field. Nathan Copeland, implanted in 2015, holds the record for longest continuous use of a brain-computer interface. In 2016, he used a robotic arm to fist-bump Barack Obama, which remains the single best piece of BCI marketing ever produced despite not being marketing at all.

    In 2025, a BrainGate team at UC Davis demonstrated that a man with ALS could speak through a BCI-driven voice synthesizer reconstructed from recordings of his pre-disease voice. More recently, a BrainGate study published in Nature Neuroscience showed two paralyzed patients typing on a standard QWERTY keyboard layout using attempted finger movements—not imagined cursor control, actual attempted typing—at speeds approaching 90 characters per minute. That’s not far from the average typing speed of a non-disabled person on a phone. The decoder is getting better because the algorithms are getting better, and the algorithms are getting better because we have more data from more patients over longer periods. This is the boring, incremental, deeply important work that doesn’t generate Musk-level headlines but is actually what moves the field forward.

    Precision Neuroscience: The one designed to come back out

    Founded by Neuralink co-founder Benjamin Rapoport, Precision takes yet another approach. Their Layer 7 Cortical Interface is an ultra-thin film—one-fifth the thickness of an eyelash—studded with 1,024 platinum microelectrodes. It sits on the brain surface without penetrating tissue, slipped through a small slit in the skull. The critical difference: it’s designed to be safely removable. Every other invasive BCI is essentially permanent. Precision’s device can come out without damaging the cortex, which is a significant advantage for a field where the long-term effects of brain implants are still being studied.

    Precision received FDA 510(k) clearance—the first full regulatory clearance for any of the new commercial BCI technologies—for implants lasting up to 30 days, and they’ve performed 38 human implant procedures. Their current application is short-term brain mapping and neural data collection, not yet chronic implantation for daily use. But the data they’re collecting is building the training sets for neural decoding algorithms that could eventually power long-term devices.

    What’s actually hard (the part nobody puts on the slide deck)

    Here’s what I think about when I read BCI press releases, and what I wish the coverage spent more time on:

    Signal degradation over time. The brain forms glial scar tissue around penetrating electrodes. The signal quality starts high and degrades over months to years as the immune response walls off the foreign object. This is the single biggest unsolved problem in chronic invasive BCIs, and no company has publicly demonstrated a solution that works at scale over five-plus years.

    The decoder problem. Current BCIs require calibration—sometimes daily—because the neural signals drift. The relationship between a specific pattern of neural activity and an intended movement isn’t fixed. It shifts as neurons adapt to the implant, as the user’s neural strategies change, and as electrodes move or degrade. Making decoders that stay accurate without constant recalibration is an active area of research, and AI is helping, but it’s not solved.

    Surgical risk. Any procedure involving the brain carries risk. Infection, hemorrhage, device failure requiring revision surgery—these are not theoretical concerns. They’re the everyday calculus of neurosurgery. Neuralink’s thread retraction in their first patient is a concrete example. Synchron’s endovascular approach has a lower risk profile precisely because it doesn’t penetrate the brain, but even catheter-based procedures have complication rates.

    The regulatory path. These devices are in early feasibility trials. The road from there to FDA-approved commercial products typically takes years—pivotal trials with larger patient populations, long-term follow-up data, manufacturing quality controls, post-market surveillance plans. Musk saying “high-volume production in 2026” doesn’t change the regulatory timeline. The FDA moves at the speed of evidence, not the speed of X posts.

    Where this goes

    The honest assessment: BCIs for people with severe paralysis will almost certainly become commercially available within the next three to five years. Not as consumer products—as medical devices, implanted by neurosurgeons, prescribed for specific clinical indications, and covered (eventually) by insurance. The first approved products will probably do what the current trials are demonstrating: cursor control, typing, basic device navigation. Not telepathy. Not memory enhancement. Not uploading your consciousness to the cloud.

    The longer-term applications—speech decoding for people who’ve lost the ability to talk, sensory feedback for prosthetic limbs, treatment of neuropsychiatric conditions—are genuinely possible but further out. They require higher-resolution interfaces, better algorithms, and a much deeper understanding of neural coding than we currently have.

    What I want people to take away from this is that the technology is real, the progress is meaningful, and the patients benefiting from these devices are experiencing something that would have been science fiction 20 years ago. But the field is in its early clinical phase, and the distance between “a paralyzed person can move a cursor” and “BCIs are a consumer product” is enormous—measured not in engineering breakthroughs but in safety data, regulatory milestones, and the slow, grinding, essential work of proving that these devices help more than they harm over the long term.

    We cover the full history, science, and engineering of brain-computer interfaces—from the earliest EEG experiments to every company and approach described above—across 48 lectures in our Neuroprosthetics & Brain-Computer Interfaces course. If this piece made you want the granular version, that’s where it lives.