Scientists recreate Pink Floyd song by reading brain signals

Scientists have trained a computer to analyse the brain activity of someone listening to music and, based only on those neuronal patterns, recreate the song. The research, published on Tuesday, produced a recognizable, if muffled version of Pink Floyd’s 1979 song, “Another Brick in the Wall (Part 1).”

Before this, researchers had figured out how to use brain activity to reconstruct music with similar features to the song someone was listening to. Now, “you can actually listen to the brain and restore the music that person heard,” said Gerwin Schalk, a neuroscientist who directs a research lab in Shanghai and collected data for this study.

The researchers also found a spot in the brain’s temporal lobe that reacted when volunteers heard the 16th notes of the song’s guitar groove. They proposed that this particular area might be involved in our perception of rhythm.

The findings offer a first step toward creating more expressive devices to assist people who can’t speak. Over the past few years, scientists have made major breakthroughs in extracting words from the electrical signals produced by the brains of people with muscle paralysis when they attempt to speak.

But a significant amount of the information conveyed through speech comes from what linguists call “prosodic” elements, like tone — “the things that make us a lively speaker and not a robot,” Dr. Schalk said.

By better understanding how the brain metabolises music, scientists hope to build new “speech prosthetics” for people with neurological diseases affecting their vocal production. The aim is for these devices to relay not only what someone is trying to say, but retain some of the musicality, rhythm and emotion of the organic speech.

To collect the data for the study, the researchers recorded from the brains of 29 epilepsy patients at Albany Medical Center in New York State from 2009 to 2015.

As part of their epilepsy treatment, the patients had a net of nail-like electrodes implanted in their brains. This created a rare opportunity for the neuroscientists to record from their brain activity while they listened to music.

The team chose the Pink Floyd song partly because older patients liked it. “If they said, ‘I can’t listen to this garbage,’” then the data would have been terrible, Dr. Schalk said. Plus, the song features 41 seconds of lyrics and two-and-a-half minutes of moody instrumentals, a combination that was useful for teasing out how the brain processes words versus melody.

Robert Knight, a neuroscientist at the University of California, Berkeley, and the leader of the team, asked one of his postdoctoral fellows, Ludovic Bellier, to try to use the data set to reconstruct the music “because he was in a band,” Dr. Knight said. The lab had already done similar work reconstructing words.

By analysing data from every patient, Dr. Bellier identified what parts of the brain lit up during the song and what frequencies these areas were reacting to.