No mind-reading yet, but scientists eavesdrop on brain impulses
You've heard of mind reading, but how about mind listening?
In a move that brings us one step closer to a world in which Big Brother could listen in on what you're hearing from inside your head, scientists have found that they can re-create a single word that a person has just heard by tracking the brain's electrical response to the sound.
Brian Pasley, a neuroscientist at UC Berkeley and lead author of the paper "Reconstructing Speech From Human Auditory Cortex," explained that the brain analyzes speech by its acoustic frequency, and that different sites in the brain respond to different frequencies. To listen in on what the brain is hearing, Pasley and his team essentially created a model, or map, of which part of the brain responded to which frequency.
But it's not like a brain wiretap is on its way anytime soon. The researchers' brain code allows them to translate only words that the brain actually hears, not words that the brain thinks up on its own.
Also, the process of listening in on what the brain hears is not a simple one — at least not yet. For this study, researchers worked with people who already had an array of electrodes placed directly on top of their actual brain as part of a treatment for eplilepsy.
"For what we are studying, it was a really unique window into what the brain is doing when we are trying to understand speech," said Pasley. "The types of signals you are getting when you are recording directly from the brain are much more precise than other methods."
Still, he said he had to play these kind volunteers a single word for five or 10 minutes before he got enough data from the brain to re-create it.
— Deborah Netburn
Image: An illustration showing a human brain with the electrode array. Credit: Adeen Flinker / UC Berkeley.