Scientifically Speaking | When brainwaves can drum up Floyd
Scientists recreated Pink Floyd’s iconic 'Another Brick in the Wall (Part 1)' from brain activity. This and other studies herald the dawn of a new era.
Earlier generations cherished long-playing vinyl records. I grew up with cassettes, which eventually gave way to CDs. Today, I have embraced streaming music online. But what comes next? Surprisingly, an unexpected detour on our musical journey might be the recreation of music directly from brain activity. This is precisely what a study published in the journal PLoS Biology last week suggests.
Music, often hailed as the universal language, resonates deeply with us. Imagine the brain as a sophisticated radio, receiving and playing tunes. Researchers at Albany Medical Centre in New York demonstrated this by recreating Pink Floyd’s iconic 'Another Brick in the Wall (Part 1)' from the brain activity.
The study involved 29 individuals, aged between 16 and 60 years, all with electrodes surgically implanted in their brains to treat drug-resistant epilepsy. Importantly, each participant confirmed they had normal hearing.
Utilising intracranial electroencephalography (iEEG), the scientists recorded the participants' brain activity as they listened to the song. For song recreation, the team adopted two techniques: A straightforward linear method and a more intricate nonlinear approach. Their findings indicated that the nonlinear approach was more accurate in capturing song details.
Interestingly, it wasn’t the number of electrodes, but their placement in the brain that was pivotal in decoding the song. Just as with speech recognition, various parts of the brain engage in musical perception. The researchers pinpointed the superior temporal gyrus in the right hemisphere as particularly significant.
Comparing the recreated track to the original, I noticed the former was somewhat muddy. However, the resemblance was uncanny. While the clarity of the recreation might not rival Pink Floyd's rock classic, the study's real revelation is our newfound ability to identify a song merely from brain activity.
Why did the scientists choose Pink Floyd, you might wonder. 'Another Brick in the Wall (Part 1)' has complex musical elements with multiple layers of harmonies, chords, and notes, they reveal. Ultimately, the deciding factor might have been the scientists' and participants’ fondness for the song.
Almost at the same time, in a preprint posted on the repository arXiv, researchers at Osaka University and Google show that it is possible to find out the kind of music someone is listening to without surgically implanted electrodes. This study, which has not yet been published in a peer-reviewed journal, analyzed data from brain scans produced through a technique known as functional magnetic resonance imaging (fMRI).
The music from fMRI scans is strikingly similar to what the participants were hearing, but not a perfect match. It did not achieve the level of precision with surgically implanted electrodes used in iEEG. As the authors of the PLoS Biology study note, "combining iEEG with computer modelling provided the first recognizable song reconstructed from direct brain recordings.”
But there is potential for mind reading beyond music. An emerging trend in neuroscience seeks to interpret perceptions directly from thoughts.
Earlier this year, in the journal Nature Neuroscience, scientists reported the creation of a decoder that can reconstruct language from fMRI scans. Three volunteers spent hours inside a scanner, listening to naturally spoken narrative stories. The decoder utilised the GPT-1, an earlier version of ChatGPT, to map brain patterns with meanings. Then, these participants were scanned while hearing a different story or imagining they were telling one. While this decoder didn’t always match exact words, around 50% of the time it was often the gist of what participants were thinking.
These studies herald the dawn of a new era. In 'Brain Damage', Pink Floyd sang, "And if the cloud bursts thunder in your ear / You shout and no one seems to hear."
Now, it appears science has found its way to listen.
Anirban Mahapatra is a scientist by training and the author of a popular science book on COVID-19. The views expressed are personal.
