Neuralink has an amazing monkey who writes words with his brain

Elon Musk is trying to help the paralyzed to move again, through electrodes in the cerebral cortex.
Stephen Vicinanza
Elon Musk's Neuralink.
Elon Musk's Neuralink.

Jakub Porzycki/NurPhoto via Getty Images

Neuralink, the strange and somewhat vague brainchild of Elon Musk, held an event Wednesday that the CEO of Tesla, SpaceX and Twitter called a “show and tell.” And show and tell it did — as a monkey welcomed the audience by typing a message through a brain-computer interface.

Neuralink's product records action potentials of neurons in the brain. This is done by placing an electrode close enough to the synapse of two neurons in the brain and taking a recording of its electrical impulse.

The National Institute of Health has determined that this methodology does not cause neuronal damage, nor does it cause harm to the host patient where the electrode is implanted. Its technical name is Deep Brain Stimulation (DBS).

Neuralink is working on an ambitious project to allow the paralyzed to move again. The project would stimulate and mirror the movement centers of the brain, where synaptic activity no longer happens, and stimulate those centers via a computer.

Show and tell

The Neuralink event started off with a slow series of letters typed out to read: “Welcome to Show and Tell.” The typist was a monkey controlling a computer with his brain. In fact, the monkey controlled the computer in a series of complex learning behaviors.

The staff at Neuralink explained how they trained the monkey to react to numbers and letters on the display. The team rewarded the monkey for tracing letters and numbers, gradually shifting to more complicated numbers and words. This led to the monkey finally producing a sentence.

An implant in the monkey's brain translates the neuronal activity in an ordered fashion. The monkey learns to control the screen by thinking about the letters.

The key to joining the brain and the computer is the electrodes implanted in the monkey's brain. These electrodes are long, thin strands of metalized fibers. They are between five and 50 microns thick, smaller than human hair. They are so light that if dropped into the air, they would float away on wind currents too weak to even move a hair.

The term high fidelity is used throughout the event, to mean a good quality response to electric stimulation. The electrodes are recording neuronal activity, signals are released from the neurons, recorded by the chip in the computer, then mapped, organized and reproduced.

The road to understanding the brain was described by one Neuralink engineer to be likened to a mile long strip that represented all the things a brain can do. If the road to understanding were a mile, we have currently only traveled the first few inches.

Neuralink revealed plans to have a one implant system, that can have ten thousand electrodes in any one thread of electrodes. The robot that implants the electrodes now is a surgical robot. The neurosurgeon preps the patient, then the robot places the implants in the brain. Because the threads of electrodes are so delicate, they cannot be held by a human hand.