The idea of connecting a human brain directly to a computer has been a staple of science fiction for decades. But it is no longer fiction. Brain-computer interfaces, or BCIs, are real devices that translate neural activity into digital signals, and Neuralink is the company that has pushed them furthest into the public spotlight. Here is what the technology actually does, how it works, and what the road ahead looks like.
A Brief History of Brain-Computer Interfaces
The concept of reading electrical signals from the brain dates back to the 1920s, when German psychiatrist Hans Berger recorded the first human electroencephalogram, or EEG. He placed electrodes on the scalp and measured the faint electrical patterns generated by neurons firing in concert. It was a crude beginning, but it proved a fundamental point: the brain’s activity could be measured from outside.
By the 1960s and 1970s, researchers were implanting electrodes directly into animal brains and demonstrating that individual neurons could be recorded. In 1998, the first implanted BCI allowed a locked-in patient — someone fully conscious but unable to move — to control a computer cursor using brain signals alone. The BrainGate project, launched in the early 2000s, built on this work and showed that paralyzed humans could type, browse the web, and even control robotic arms through implanted electrode arrays.
These early systems were groundbreaking but limited. The electrode arrays were rigid, the surgery was invasive, and the devices could record from only a few hundred neurons at a time. Neuralink entered the picture with a plan to change all of that.
How Neuralink’s Device Works
Neuralink’s implant, called the N1, is a small disc-shaped device roughly the size of a coin. It sits flush with the surface of the skull, completely hidden beneath the skin. From the bottom of the device, thin flexible threads extend down into the brain’s cortex.
The N1 Chip. The N1 contains custom-designed chips that amplify, digitize, and wirelessly transmit neural signals. It has 1,024 electrodes distributed across 64 threads, each thinner than a human hair. The chip processes signals on board, compressing the data before sending it via Bluetooth to an external device like a phone or computer. It is powered by a small battery that charges wirelessly through the skin, similar to how a wireless phone charger works.
Electrode Threads. The threads are one of Neuralink’s key innovations. Earlier BCI systems like the Utah Array used rigid silicon needles that could damage brain tissue over time. Neuralink’s threads are made of a flexible polymer, which moves with the brain rather than against it. This flexibility is intended to reduce the inflammatory response that causes scar tissue to form around implants, which gradually degrades signal quality. Each thread carries multiple electrodes along its length, allowing the device to record from neurons at different depths in the cortex.
The Surgical Robot. Implanting threads thinner than a hair into brain tissue is not something a human surgeon can do by hand with sufficient precision. Neuralink developed a custom surgical robot, called the R1, to handle the insertion. The robot uses a needle finer than a sewing needle to stitch each thread into the brain while avoiding blood vessels visible on the surface. The goal is to make the procedure as fast and minimally invasive as possible, ideally something that could eventually be performed as an outpatient procedure.
Human Trials
Neuralink received FDA approval for human clinical trials in 2023 and implanted its first human patient, Noland Arbaugh, in early 2024. Arbaugh, a quadriplegic, was able to control a computer cursor and play video games using only his thoughts within days of the surgery. He described the experience as intuitive, comparing it to using the Force from Star Wars.
The early results were not without complications. Some of the threads retracted from the brain tissue after implantation, reducing the number of functioning electrodes. Neuralink adjusted its software algorithms to compensate, and subsequent patients have reportedly experienced improved outcomes. As of early 2025, Neuralink has implanted several patients and continues to refine both the hardware and the surgical process.
The company’s stated near-term goal is to restore autonomy to people with severe paralysis — enabling them to control phones, computers, and eventually robotic limbs with their thoughts. The longer-term vision, as described by founder Elon Musk, extends to cognitive enhancement and what he calls “symbiosis with artificial intelligence,” though those ambitions remain far from realization.
The Competition
Neuralink gets the most attention, but it is not the only company building brain-computer interfaces. Understanding the competitive landscape helps put its approach in context.
Synchron takes a less invasive approach. Instead of opening the skull, Synchron threads a small electrode array called a Stentrode through the blood vessels, navigating it to the brain’s motor cortex the same way a cardiologist threads a stent to the heart. The device records signals through the vessel wall. It captures fewer neurons than Neuralink’s implant, but the procedure is dramatically simpler and has already been performed on multiple human patients. Synchron received FDA approval for human trials before Neuralink did.
Blackrock Neurotech has the longest track record. Its Utah Array has been used in BCI research for over two decades and has been implanted in more human patients than any other device. Blackrock is developing next-generation arrays with more electrodes and wireless capabilities, aiming to bridge the gap between research-grade hardware and a commercial product.
Precision Neuroscience was founded by a Neuralink co-founder and uses a thin-film electrode array that sits on the brain’s surface rather than penetrating it. This approach sacrifices some signal resolution but is reversible and less risky.
Each company represents a different tradeoff between invasiveness, signal quality, and safety. It is not yet clear which approach will win out, and the answer may depend on the application.
Ethical Concerns
Brain-computer interfaces raise ethical questions that are as complex as the technology itself.
Privacy. A device that reads brain activity generates extraordinarily sensitive data. Neural signals can potentially reveal not just motor intentions but emotional states, cognitive patterns, and eventually even fragments of thought. Who owns this data? Who can access it? Current privacy laws were not written with brain data in mind, and the regulatory framework is still catching up.
Equity and access. If BCIs eventually enhance cognitive performance, they could create a new dimension of inequality. People who can afford neural implants might gain advantages in learning, memory, or decision-making that are unavailable to everyone else. This is not an immediate concern — current devices are focused on restoring lost function, not augmenting healthy brains — but the trajectory demands proactive consideration.
Consent and autonomy. For patients with severe disabilities, the benefits of a BCI may clearly outweigh the risks. But as the technology becomes more capable, the line between medical device and consumer product will blur. Questions about informed consent, the right to disconnect, and the psychological effects of merging human cognition with machine intelligence will need answers.
Security. Any wireless device connected to the brain is, in principle, hackable. The consequences of a security breach in a neural implant are far more serious than a compromised email account. Neuralink and its competitors will need to meet security standards that do not yet exist.
What Comes Next
The near future of BCIs is focused on medical applications. Restoring communication and mobility to people with paralysis is an achievable, meaningful goal that justifies the risks of an invasive procedure. Beyond that, researchers are exploring BCIs for treating depression, epilepsy, PTSD, and chronic pain by modulating neural circuits directly.
The further future is harder to predict. If BCIs become safe, reliable, and affordable, the potential applications expand enormously — from immersive computing interfaces that bypass screens and keyboards to direct brain-to-brain communication. These possibilities are speculative but no longer absurd.
What is certain is that the barrier between biology and technology is getting thinner. Neuralink did not invent the brain-computer interface, but it has accelerated the field, attracted public attention, and forced a broader conversation about what it means to connect a human mind to a machine. The answers to that question will shape not just medicine, but the future of what it means to be human.