Pager, a nine year old Macaque Monkey had bilateral neuralink implants placed on each side of his brain. The Neuralinks or 'links' download neuronal activity which can then be paired to a decoder algorithm that is then paired with a wireless electrical device such as a game console. In this latest experiment, Pager is able to play pong with brain activity alone!
If you wanted a deeper dive into Neuralink, see our article on a prior experiment with Gertrude the pig here.
How did they train Pager? They rewarded him with a banana is the simple answer.
The more detailed answer is that they implanted two links in Pager's brain right on the motor cortex which is a section of the brain that controls movement. Different areas of the motor cortex firing correspond to different muscle groups becoming activated and voila--movement! The link itself is pretty small. In order to achieve the ability to record neurons firing, it has to use neural threads--small flexible threads that contain electrodes to detect electrical activity in the cortex. This is far more accurate than an EEG placed on the skin surface. Now with the links in place, Pager simulated hand movements on a joystick and the motor cortex readings were recorded. Do this enough times and you'll be able to tell which readings correspond with an up, down, left, or right hand movement. Then in the second part of the experiment, the joystick is disabled but the links are able to decode the new neuron firings as up, down, left, right and transmit those signals to the screen. Thereby allowing Pager to play pong on a screen using brain signals only.
The idea of a Brain Controlled Interface (BCI) or Brain Machine Interface (BMI) or Brain Computer Interface (BCI) or just simply a man-machine interface has been known for a while. In fact you can't find a scientific study that doesn't reference a 1970 paper by Donald R. Humphrey, E. M. Schmidt and W. D. Thompson titled Predicting Measures of Motor Performance from Multiple Cortical Spike Trains which successfully recorded cortical activity of unanesthetized monkeys as they performed arm movements.
There are multiple studies and progress since then including the use a neural interface system called the BrainGate2 in 2012 to allow tetraplegic patients to direct movement of robotic arms. This required a microelectrode array to be implanted in the motor cortex in order to record neural signals similar to Elon Musk's Link today. While you may hear that scientists and physicians are doubting Neuralink's success--that really can't be true since its the same experiments that have been done for decades.
What is new about neuralink is the miniaturization of the device, the ease of implanting the link (developed special implant procedure), the amount of data collected, and the backend algorithms that are able to process this information. The links in Pager's experiment took 6 weeks to achieve a high enough accuracy. Soon it will take a few minutes of calibration (joystick) and decoding (without joystick).
To work for paralyzed individuals, it would need a fast feedback loop where said person would 'think' of moving right and the link would record that movement--repeat enough times and moving a cursor to the right on a screen becomes possible. However again to clarify--this was actually achieved in 2006 where tiny electrodes were implanted in a man paralyzed below the neck after which he was able to move the cursor control on a screen. Proving it works is not what Elon is doing--we know it works!
What Elon is doing is commercializing the entire implant to rehab to remote software updates lifecycle. That's what we currently lack--the optimization of the device and processes such that it can be commercialized at scale to impact all those suffering today. He is such a good marketer going from pig to monkey to human eventually and giving them all names (hopefully the human comes with their own name already). That's how you build marketing momentum!
The full video of Pager's success is shown below:
They are actively hiring for the next phase of growth--so If you happen to be a pathologist looking to get out of the basement of your hospital and work on an interesting project that is more importantly funded for years to come then apply here.