Chrome and Consequences: The Science and Fiction of Cyberpunk’s Implants

In Night City, getting an upgrade is as normal as getting a haircut. You walk into a ripperdoc’s clinic, choose a new pair of eyes or a faster spine, and walk out a little less human. That idea, that the body is just hardware waiting for better parts, sits at the centre of Cyberpunk 2077 and of the anime Cyberpunk: Edgerunners.

With Edgerunners 2 landing on Netflix three days ago, this felt like the right month to step away from research papers and ask a different question: how much of Night City’s chrome could we actually build? I go through six implants from the game and the series, find the closest real technology for each, and look at two darker ideas the story keeps returning to: machines that think for themselves, and minds that crack under too much metal.

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The chrome catalogue: fiction against today

Here are six implants from the game and the series, each set against the closest thing that exists in 2026. Tap a marker on the body, or a tab, to see what each implant does in Night City, its closest real counterpart, and how far that counterpart has got.

Sandevistan: the reflex booster

The Sandevistan is the implant that defines Edgerunners. Installed along the spine, it boosts the user’s nervous system so that everything around them seems to crawl. In the game it is an operating system for your body; in the anime it is the military-grade chrome David Martinez builds his life around.

A real human reaction is surprisingly slow. Light has to be turned into nerve signals in the eye, the brain has to recognise what it saw and decide, and the command has to travel down nerves to a muscle that then needs time to tense. In a lab, pressing a button when a light comes on takes most people around a quarter of a second.

No technology speeds up thought itself, but one clever experiment skips part of the queue. Shunichi Kasahara, Jun Nishida and Pedro Lopes used electrical muscle stimulation to fire the arm’s muscles 160 ms after a target appeared, before most people would have moved on their own. In their first study, participants reacted about 80 ms faster, and most still felt the movement was their own. Fire the stimulation much earlier and the gain grows, but people start to feel that the machine moved them.

The real version is far less cinematic. Here is what that 80 ms head start looks like, slowed down ten times.

Arms and hands: Gorilla Arms and Mantis Blades

Night City sells arms that punch through car doors and forearms that unfold into blades. Real prosthetic arms are far more modest, but they are no longer just hooks. Myoelectric hands read the electrical signals of the muscles left in the arm, the DEKA “LUKE” arm was cleared in the US in 2014, and bone-anchored implants let a prosthesis attach straight to the skeleton. The hard part isn’t strength, which a motor can supply easily. It is control and feeling: getting many fingers to do what you intend, and getting touch to flow back to the brain.

Legs: Reinforced Tendons and Lynx Paws

In the game, leg chrome gives you a double jump and silent footsteps. The real headline is quieter but remarkable. In 2024 an MIT team led by Hugh Herr reported a bionic leg controlled directly by the nervous system. Surgeons reconnected pairs of muscles in the residual limb so they still pull against each other, which lets the brain sense where the artificial ankle is. Seven people with these connections walked with a more natural gait and reached top walking speeds 41% higher than a matched group without them. Not a double jump, but a body that treats the machine as its own.

Optics: Kiroshi eyes

Kiroshi optics zoom, scan people for data and overlay a heads-up display on the world. Real implants are still fighting to restore basic sight. The PRIMA chip from Science Corporation is just 2 × 2 mm and sits under the retina, turning infrared light from a camera in a pair of glasses into signals for the remaining retinal cells. In a trial reported in the New England Journal of Medicine in October 2025, 38 people with age-related macular degeneration took part, and 80% of them gained clinically meaningful reading vision, on average 25 more letters on an eye chart. It has a CE mark in Europe. The images are grainy and black and white, and nobody is zooming, but people who couldn’t read are reading again.

Biochips: a computer in your head

The Relic is the chip at the heart of Cyberpunk 2077: an Arasaka biochip that can hold a human mind, slotted into the back of your neck. The real counterpart is the brain–computer interface. Neuralink had implanted 21 people in its trials by January 2026, letting people with paralysis move a cursor or type by thought, alongside devices from groups such as BrainGate, Synchron and Precision. These read intentions from a small patch of cortex. None of them stores memories, writes thoughts, or holds a personality.

Engrams: a mind as data

The game’s big twist is that the Relic carries an engram, a digital copy of the rockerboy Johnny Silverhand, made by a program called Soulkiller. Johnny slowly overwrites the mind of the player character, V. It is the most fictional idea here, and also the one that connects most closely to real neuroscience.

To copy a mind you would first need its wiring. In my Talk 08 review, the first complete wiring diagram of an adult fly brain had 139,255 neurons. In 2025 the MICrONS project mapped one cubic millimetre of mouse brain, 84,000 neurons and over 500 million synapses, in 1.6 petabytes of data after almost a decade of work. A human brain has around 86 billion neurons. And even a perfect map isn’t a mind: when I ran a published model of the fly brain as a hobby project, it predicted feeding behaviour well, but it leaves out chemistry, learning and everything that makes one fly different from another.

Talk 08: The Whole Fly, Wired → · My fly brain simulation →

Every real implant in this list restores something a person lost. None of them yet makes a healthy person more than human.