Jennifer Ouellette in Ars Technica:
Coming on the heels of the Neuralink announcement earlier this month—complete with video showing a monkey playing Pong with its mind, thanks to a wireless brain implant—researchers with the BrainGate Consortium have successfully demonstrated a high-bandwidth wireless brain-computer interface (BCI) in two tetraplegic human subjects. The researchers described their work in a recent paper published in the journal IEEE Transactions in Biomedical Engineering.
BCIs interact with brain cells, recording the electrical activity of neurons and translating those signals into action. Such systems generally involve electrode sensors to record neuronal activity, a chipset to transmit the signals, and computer algorithms to translate the signals. BCIs can be external, similar to medical EEGs in that the electrodes are placed onto the scalp or forehead with a wearable cap; or they can be implanted directly into the brain. The former are less invasive but can be less accurate because there is more noise interfering with the signals; the latter require brain surgery, which can be risky.