Using brain interfaces to learn about learning
- Bryan Walsh, author of Axios Future

Illustration: Eniola Odetunde/Axios
A new study uses a brain-computer interface (BCI) to observe the neural activity in monkeys during the process of learning.
Why it matters: The internal state of the brain is often a mystery — including to ourselves — but new neural interfaces are making it easier for scientists to observe the mind in action.
How it works: In a paper published recently in Nature Neuroscience, a large team of researchers hooked up a group of monkeys to BCIs while the study subjects were trained to play a basic computer game.
Details: The researchers found that neural fluctuations took place when the monkeys were surprised by something happening during the game.
- Those monkeys that showed greater engagement performed better during following rounds of the test, indicating that arousal and engagement — internal states that can be difficult to track without a BCI — can affect the act of learning something new.
What they're saying: "Our understanding of what happens in the brain as one learns is super limited right now," says Byron Yu, a professor at Carnegie Mellon University and a co-author of the paper. But BCI "gives us an amazing window into how this happens."
Context: BCI technology has emerged as a major area of scientific research and increasingly consumer technology as the interfaces have slowly improved.
- On Friday, Elon Musk's BCI company Neuralink released a video of a monkey with chips embedded on each side of its brain as it played a basic video game using only its thoughts.

Yes, but: BCI technology would have to progress significantly — and the applications would need to go beyond video games — before many people would be willing to have an interface drilled into their skull.