Synchron · Grey Matter

Synchron is a neurotechnology company, started in Australia and now based in New York, that develops the Stentrode, a brain-computer interface placed through the blood vessels instead of through the skull, and it was the first company to receive US permission to test a permanently implanted BCI.

Synchron. Synchron is a neurotechnology company, started in Australia and now based in New York, that develops the Stentrode, a brain-computer interface placed through the blood vessels instead of through the skull, and it was the first company to receive US permission to test a permanently implanted BCI.

Its bet is on the procedure more than the signal. The Stentrode reaches the motor cortex by catheter through the jugular vein, the way stents reach the heart, so implantation needs a catheter lab and an interventional specialist rather than open neurosurgery. The cost is resolution: sixteen electrodes inside a vein record population activity, enough for reliable clicks and selections, short of the fine control that penetrating arrays give.

Its first evidence came from animals. The stent electrode was shown in sheep in 2016, recording cortical activity from inside a vein over months with the device incorporated into the vessel wall.

Its trials have moved from Australia to the United States. Four people were implanted in Australia, then six in the US COMMAND early feasibility study, which reported no serious device-related adverse events.

It is preparing a pivotal trial, the step before applying for market approval, funded by a 200 million dollar round closed in November 2025.

Questions: How does Synchron's Stentrode reach the motor cortex without opening the skull? It travels through the veins. A catheter enters the internal jugular vein in the neck and is steered up into the superior sagittal sinus, a large vein along the top of the brain that lies against the motor cortex, where a self-expanding stent carrying 16 electrodes is released against the vessel wall. A lead runs back down the vein to a unit in the chest that transmits the signals wirelessly, and the whole procedure resembles placing a stent in the heart more than brain surgery. What happens to people with implants if the company that made them stops supporting the device? The precedent is the Argus II retinal implant: its maker, Second Sight, stopped producing it in 2019 and nearly shut down in 2020, leaving more than 350 implanted people without repairs, replacement parts or reliable information for medical procedures. Every young neurotechnology company, Synchron among those now preparing for market approval, faces the same question, since venture-funded firms can pivot, merge or fail while their devices stay in people's bodies. Reviews of neural device research ask that support after a trial, and plans for a company's failure, be settled before implantation rather than after.