Neuroscientists Decoded People’s Thoughts Using Brain Scans

Much like Dumbledore’s magical staff, a scanning technique can extract lengthy narratives directly from someone’s mind — granted the individual is willing.

Detailed on May 1 in Nature Neuroscience, this “telepathic” achievement is still in its infancy and not yet ready for deployment beyond advanced labs. However, the eventual aim is to develop user-friendly tools that aid those with communication challenges.

The findings, though, ignite debates over potential privacy intrusions due to unwanted brain monitoring. Unlike recently successful embedded devices, this novel approach doesn’t necessitate invasive procedures.

Differing from other non-invasive methods, this one yields continuous word sequences, bypassing limited word banks. In the conducted research, three participants spent a minimum of 16 hours inside a sizable MRI apparatus.

They were engrossed in stories, primarily from The Moth podcast, as functional MRI screenings monitored brain blood flow variations, which, albeit not flawless, indicate brain activity.

Using this neural information, computational neurologists Alexander Huth and Jerry Tang from the University of Texas at Austin, along with their team, could associate specific brain activity with particular words and thoughts.

Their technique leveraged a language model developed using GPT, a precursor to current AI conversational systems. Understanding the brain activity aligned with story words enabled the scientists to reverse-engineer, utilizing brain patterns to anticipate fresh words and concepts.

This method was iterative: A decoding system gauged potential subsequent words based on prior ones, consulting brain patterns to select the most fitting term, eventually discerning the core message.

Interestingly, it was evident that these decoders had issues with pronouns, and the reason remains elusive to the team. The decoding tools could also approximate narratives in two situations: when individuals mentally recited a memorized tale and while observing mute films.

The rapid progression in neural decoding prompts contemplation on mental confidentiality, which the researchers acknowledged. However, they discerned that their technique isn’t universally applicable.

Each decoder was tailored to the individual whose neural information contributed to its design. Importantly, an individual’s conscious participation was essential for successful decoding.

If they diverted their attention from an auditory tale, the decoder failed to interpret it. Participants could deter any invasive attempts by simply diverting their focus—whether contemplating animals, solving arithmetic, or immersing in an alternative narrative.