The brain chip, which Musk describes as a “Fitbit for your skull,” was implanted in its first live patient at the beginning of 2024. It allows the patient, who lost all movement and sensation in his arms and legs after an accident, to operate a computer and play Chess using this mind.

Neuralink will start high-volume production of brain-computer interface devices and move to a streamlined, almost entirely automated surgical procedure in 2026. Device threads will go through the dura...