Overview

An AI-powered technique designed to decode brain scans lets scientists know what you’re thinking. While reading someone’s thoughts might sound a bit “creepy”, this technology could help those who are unable to communicate through speaking or typing.

The science and other stuff to know

The new non-invasive breakthrough was developed by a group of scientists at the University of Texas, The Scientist reported. According to the study, preprinted in BioRxiv, the method works by feeding functional magnetic resonance imaging (fMRI) to a decoder, which then reconstructs arbitrary stimuli that the person is hearing or thinking into natural language. This is a significant advancement, as previously, mind-reading techniques depended on implanting electrodes deep within peoples’ brains

The team scanned the brains of one woman and two men in their twenties and thirties for the new study, which has not yet been peer-reviewed. Over several scanner sessions, each participant listened to a total of 16 hours of various podcasts and radio shows. These scans were then fed into a computer algorithm known as a “decoder,” which compared patterns in the audio to patterns in the recorded brain activity.

Although the technique isn’t able to break down every “word” in the individual’s thoughts, it’s able to decipher the story each subject heard, providing an idea of what they are thinking. It could even retell a story that the participants imagined telling in their heads.

The algorithm, however, isn’t foolproof as it did a few mistakes, like switching up characters’ pronouns and the use of the first and third person. It “knows what’s happening pretty accurately, but not who is doing the things,” senior author Alexander Huth, a neuroscientist at the University of Texas at Austin, told The Scientist.

So what?

“If you had asked any cognitive neuroscientist in the world 20 years ago if this was doable, they would have laughed you out of the room,” Huth told The Scientist. Until now, reading someone’s thoughts has only been achieved by implanting electrodes in the brain. But this new method is noninvasive and produces better results than previous techniques.

In the long term, the research team aims to develop this technology so that it can be used in brain-computer interfaces designed for people who can’t speak or type. It could also help investigate mental heal conditions.

What’s next?

Previous studies have demonstrated it’s possible to know what someone is thinking by scanning their brain. Some scientists have even developed a mind-reading tech that translates brainwaves into photos. But this new study is a huge step into solving one of the mysteries of our mind as it can decipher thoughts into texts.

Despite some privacy concerns, researchers assured that their new technique couldn’t be used to read a person’s mind without their knowledge or consent. “A decoder trained on one individual’s brain scans could not reconstruct language from another individual,” Huth said.