Brain-Computer Interface

A brain-computer interface (BCI) is a system that records neural activity and translates it into commands for an external device, or delivers information back into the nervous system, bypassing the body's normal muscular or sensory pathways. Jacques Vidal coined the term in 1973. Clinical BCIs advanced through the 2000s and 2010s with devices letting people with paralysis control cursors and robotic arms using implanted or surface electrodes, mostly in small university-run trials.

A commercial push followed in the mid-2020s. Neuralink's N1 implant, a coin-sized device reading from roughly 1,000 electrodes on threads placed by a surgical robot, began human trials in 2024 under its PRIME study. By mid-2026 the company reported around 21 to 26 participants across sites in the US, UK, Canada, and UAE. It had also tested a "transdural" insertion technique that threads electrodes through the brain's protective membrane without cutting it open, first used on a Canadian ALS patient in May 2026. Participants have used implants to control a cursor and games, and in individual cases a robotic arm and generative art tools. The FDA granted Neuralink a Breakthrough Device Designation for a speech-restoration application in May 2025. Competing approaches include Synchron's stent-based endovascular BCI, which reaches the brain through blood vessels rather than open surgery.

BCIs split broadly into invasive designs implanted under the skull, which offer higher resolution at surgical risk, and non-invasive designs such as EEG caps, which are safer but noisier. Every clinical BCI on the market remains an investigational device aimed at restoring function lost to conditions like ALS or spinal cord injury. Commentators have noted tension between that medical framing and public statements from BCI companies about enabling general human-machine "symbiosis," since regulatory approval and insurance reimbursement depend on the narrower, medical claim.