In January 2024, a 29-year-old quadriplegic named Noland Arbaugh underwent a two-hour surgery at the Barrow Neurological Institute in Phoenix during which a robotic system threaded 64 ultra-thin polymer filaments — each thinner than a human hair — carrying 1,024 electrodes into the motor cortex of his brain. The device they were connected to, Neuralink’s N1 implant, is a wireless, rechargeable chip roughly the size of a quarter that sits flush against the skull, invisible from the outside. On his first day using the device, Arbaugh broke the world record for brain-computer interface cursor control speed, hitting 4.6 bits per second. By May 2024, he’d pushed that to 8.0 bits per second. By the end of the year, Neuralink claimed he’d exceeded 9 bits per second — approaching the median able-bodied mouse user’s roughly 10 bits per second. He was playing chess, browsing the internet, drawing digital images, playing Civilization VI and Mario Kart, sending messages, and livestreaming on X, all by thinking about moving his fingers. He hadn’t moved his fingers since a diving accident dislocated two vertebrae in 2016. “Y’all are giving me too much,” Arbaugh said in an early update. “It’s like a luxury overload. I haven’t been able to do these things in 8 years, and now I don’t know where to even start allocating my attention.”
That was Patient 1. As of early 2026, Neuralink has implanted 21 people.
What the first patients experienced
The story of the first year of human Neuralink implants is a story about a device that works, a device that broke, and a device that was fixed — in that order. About a month after Arbaugh’s surgery, the thread retraction problem hit. Several of the ultra-thin electrode threads pulled back from Arbaugh’s brain tissue, reducing the number of active electrodes to roughly 15% of the original 1,024. Performance degraded sharply. Arbaugh described the prospect of losing the device’s benefits as emotionally devastating — he’d had eight years of quadriplegia, six weeks of restored digital independence, and was now watching that independence degrade in real time. The FDA had flagged thread retraction as a potential risk during the approval process. Reuters reported that Neuralink had observed similar retraction in animal testing. The fact that the most predictable failure mode was the one that actually materialized was not reassuring.
Neuralink’s response was a software workaround. Engineers modified the decoding algorithms to extract more signal from fewer electrodes, compensating for the hardware loss through computational gain. By July 2024, the threads had stabilized — no further retraction — and Arbaugh’s performance had recovered to competitive levels. For subsequent patients, Neuralink modified its surgical technique. The second patient, identified publicly only as “Alex,” received his implant in July or August 2024 and did not experience thread retraction. Alex — who has a spinal cord injury — has used the device for CAD design work, gaming, and daily computer tasks. A third patient was disclosed by Elon Musk in January 2025 during an online interview. By mid-2025, nine patients had been implanted. Two of them received their implants on the same day in late July 2024 — a scheduling milestone that signaled Neuralink’s surgical capacity was scaling faster than the typical early-stage medical device trial, where patients are separated by weeks or months for safety monitoring.
The most consequential patient story after Arbaugh belongs to Brad Smith, an ALS patient who is completely non-verbal and cannot move anything except his eyes. Smith relies on a ventilator to stay alive. Before Neuralink, his communication options were limited to eye-tracking systems with slow, frustrating interfaces. After receiving the N1 implant, Smith used the device to control a computer cursor, navigate a MacBook Pro, and — in an April 2025 video posted on X — narrate his own story using an AI-generated replica of his pre-ALS voice, cloned from past recordings and controlled in real time through the brain-computer interface. The practical consequence of combining a Neuralink BCI with voice-cloning AI is that a person who has lost the ability to speak can produce speech that sounds like them, in real time, by thinking about what they want to say. Whether that qualifies as “communicating using telepathy,” as Neuralink has described it, depends on your tolerance for marketing language. What it definitely qualifies as is a functional communication channel that didn’t exist for Smith before the implant.
What the device actually is — and isn’t
Arbaugh’s 10-hour-per-day usage by August 2025 — 18 months post-surgery — is the most important data point in the entire PRIME study, because it’s a usage metric, not a performance metric. Usage measures whether a real person with a real disability finds the device useful enough to use it all day. The answer, for Arbaugh, is yes: he uses the Neuralink to study, read, game, schedule interviews, manage everyday tasks, and communicate. He has re-enrolled in college and started a business. The device needs to be charged roughly every five hours, which means he charges it during breaks the way someone charges a phone — an annoyance, not a dealbreaker. Calibration is a more significant friction. Arbaugh has described spending as long as 45 minutes recalibrating the mapping between his imagined movements and the cursor — a process that degrades over hours and days as neural patterns shift. Neuralink’s engineering team has been iterating on the calibration software throughout the trial, and the recalibration time has reportedly decreased, but it remains the single biggest UX friction in the system.
The N1 implant is wireless — a meaningful distinction from competitors like Blackrock Neurotech, whose Utah Array system requires a wired connection through the skull to an external receiver. Wireless operation means patients can use the device without being tethered to equipment, which is the difference between a research tool and something that functions in daily life. The tradeoff is battery life, power management, and data throughput — the wireless link constrains how much neural data can be transmitted in real time, which in turn constrains the decoding algorithms’ resolution.
What the device is not — at least not yet — is a general-purpose neural interface. The N1 implant records from the motor cortex, which handles planned movements. The current decoding pipeline translates imagined finger and hand movements into cursor position. It does not read thoughts. It does not access memory. It does not interface with emotions or subjective experience. It maps one specific category of neural activity — motor intention — to one specific category of output — cursor control. Within that narrow channel, it works remarkably well. The breadth of what Arbaugh does with cursor control — gaming, browsing, studying, communicating — demonstrates that cursor control on a standard computer is a surprisingly powerful restoration of independence for someone who previously needed a mouth stick placed by a caregiver to interact with a screen.
The competitive landscape
The framing that Neuralink is “first” requires qualification. A 2025 systematic review estimated that approximately 80 people worldwide had received implantable brain-computer interfaces before Arbaugh’s surgery. BrainGate, the academic BCI consortium led by Brown University, has been implanting patients since 2004 using Blackrock Neurotech’s Utah Array — a rigid silicon electrode array that preceded Neuralink’s flexible threads by two decades. Arbaugh was the first recipient of a Neuralink implant. He was not the first person to control a cursor with a brain implant. What Neuralink brought to the field was engineering scale: wireless operation, 1,024 electrodes (versus BrainGate’s roughly 100), robotic surgical insertion, and — critically — the funding and marketing infrastructure to run a multi-country clinical trial at a pace academic labs cannot match.
The competitors are not standing still. Synchron, an Australian-American company, takes a less invasive approach — its Stentrode device is inserted through the jugular vein and lodged in a blood vessel adjacent to the motor cortex, avoiding open brain surgery entirely. Synchron has its own human patients and its own clinical trial. Precision Neuroscience uses a thin, flexible electrode array called Layer 7 that sits on the brain’s surface rather than penetrating it, and can be removed without permanent tissue damage. Blackrock Neurotech has two decades of implant data and is developing its own wireless system. Paradromics is building a high-bandwidth BCI called Connexus designed for thousands of simultaneous channel recordings.
Each approach trades off invasiveness against signal quality. Neuralink’s penetrating electrodes produce the highest-resolution recordings but carry the highest surgical risk and face challenges like thread retraction. Synchron’s endovascular approach is safer but records from fewer neurons at lower resolution. Precision’s surface electrodes are reversible but may not capture the single-neuron resolution that enables the fastest cursor control. The field is converging on the same functional goals — motor control restoration, communication for non-verbal patients, and eventually sensory restoration — through fundamentally different engineering strategies.
What’s coming next
Neuralink’s pipeline beyond the N1 motor cortex implant includes two FDA Breakthrough Device designations that define where the company is heading. In September 2024, the Blindsight implant — designed to stimulate the visual cortex to restore limited vision in people who have lost both eyes or their optic nerve — received Breakthrough Device status. Musk has claimed Blindsight will enable blind people to see, though IEEE Spectrum and other expert outlets have noted that the resolution achievable with current electrode density is likely to produce something closer to phosphene patterns than natural vision. Human trials for Blindsight were projected for late 2025 or early 2026. In May 2025, Neuralink received a second Breakthrough Device designation for a speech restoration system targeting people with ALS, stroke, cerebral palsy, and spinal cord injuries — a system that would decode attempted speech movements from motor and language areas, potentially enabling more natural communication than cursor-based text output.
The operational scale is also shifting. Neuralink’s PRIME trial expanded from the United States to Canada (with Toronto’s University Health Network performing Canada’s first Neuralink surgeries in August and September 2025), the United Kingdom, and the United Arab Emirates. The trial enrolled 21 participants by early 2026. A $650 million Series E round in June 2025 valued the company at $9 billion. Neuralink has announced plans for high-volume production and automated surgical procedures targeting 2026 — a transition from artisanal neurosurgery to something closer to industrial medical device deployment. Whether the surgical robot, the implant reliability, and the regulatory pathway support that transition at Musk’s stated timeline is the open question. If any theme emerges from Neuralink’s first two years of human data, it’s that the device works better than skeptics expected and slower than Musk promised — which, for a medical device that is literally inside someone’s brain, is probably the right place to be.
The honest assessment
Neural engineering expert Kip Ludwig, quoted by Reuters after Arbaugh’s initial demonstration, said the results were promising but not a breakthrough — that the technology remained at an early stage. Neuroscientist Miguel Nicolelis noted that similar multi-electrode recordings had been achieved in his laboratory in the early 2000s. Both points are technically accurate and contextually incomplete. What Neuralink has done that prior BCI research did not is produce a wireless, fully implanted, cosmetically invisible device that a quadriplegic person uses for 10 hours a day to manage his daily life, attend college, and run a business — and then demonstrated it could be replicated across 21 patients in four countries within two years. The individual technical components are not novel. The integration into a device that functions as a consumer product for people with severe disabilities — rather than as a laboratory research tool — is novel. Whether the thread retraction problem, the calibration friction, the five-hour battery life, and the motor-cortex-only decoding pipeline are solvable engineering problems or fundamental constraints will determine whether Neuralink becomes a medical device company or remains an expensive research project. The first two years of human data suggest the former, but the history of medical devices that looked promising at 21 patients and failed at 2,100 is long enough that no honest assessment would call the outcome settled.
This is the kind of technology our Neuroprosthetics course was built to explain — where a chip the size of a quarter and 1,024 electrodes thinner than a human hair gave a man who hadn’t moved his fingers in eight years the ability to beat the world record for BCI cursor control on his first day, and then spent the next 18 months teaching us what “working” actually means when the device is inside a living brain.