A monkey controls his robotic arm with a brain-machine interface.
If this monkey can eat marshmallows with his robotic arm, mind-controlled prosthetics for humans can’t be far off, right? Well, that’s true if all you ever wanted to do with your prosthetic was sit strapped in a chair reaching for marshmallows. But as Michael Chorost explains in a recent feature for Wired, challenges abound when building an arm that works in everyday life.
Over the course of a day, you might use your arm to pick up a chair, unzip your jacket, or scratch your neck—each one of these actions are unique. But statistical algorithms used now can translate the firing of neurons into only a few stereotyped motions. And it’s not just about writing better algorithms; it’s an input problem too. Getting electrodes to pick up signals from the same neurons over time is a continuous battle against the body’s natural defenses: