Parts Of Brain Gate

The Chip

A 4-millimeter square silicon chip studded with 100 hair-thin microelectrodes is embedded in Nagle’s primary motor cortex — the region of the brain responsible for controlling movement.

The Connector

When Nagle thinks “move cursor up and left” (toward email icon), his cortical neurons fire in a distinctive pattern; the signal is transmitted through the pedestal plug attached to his skull.

The Converter

The signal travels to a shoebox-sized amplifier mounted on Nagle’s wheelchair, where it’s converted to optical data and bounced by fiber-optic cable to a computer.

The Computer

Brain Gate learns to associate patterns of brain activity with particular imagined movements — up, down, left, right — and to connect those movements to a cursor.