What occurs within the human brain? For years, scientists have tried to understand what and how the brain senses. A new study has made strides in the neural field by successfully “decoding” the brain’s electrical activity and reconstituting it as recognized music.
Pink Floyd’s renowned “Another Brick in the Wall Part 1” was played to 29 individuals while the researchers analyzed their brain activity using arrays of electrodes put directly on the brain’s surface. The tune was then reconstructed using advanced AI models from the electrical activity captured.
The findings of the study were published in PLOS Biology on August 15th.
This is the first time scientists have used neural data to recreate a recognized, albeit slightly distorted, song
Scientists have already succeeded in reconstructing what the brain senses from recorded neural signals. There have been successful attempts in the past to recreate words and images using signals acquired by implanted electrodes.
However, this is the first time scientists have used neural data to recreate a recognized, albeit slightly distorted, song.
What is the significance of recreating a Pink Floyd song from listeners’ brain waves?
The findings of this study could aid in the development of better brain-computer interfaces and assistive devices that translate brainwaves into speech for people who are unable to communicate due to stroke paralysis. After he lost his ability to talk, he communicated through a speech-generating apparatus, which improved over time. Even at its best, the generated speech sounded robotic, with no expression.
According to the study’s primary author, Ludovic Bellier, “No matter the language, speech contains melodic nuances, such as tempo, stress, accents, and intonation… [which] carry meaning that we can’t communicate with words alone.”
Electrodes inserted on the surface of the brain
While promising, there are significant obstacles to overcome before this type of technology can be made available to customers, perhaps none more so than the insertion of electrodes on the brain itself.
The current technology for recording the necessary brain waves is simply not sensitive enough to function on the scalp itself. This necessitates surgical implants, which would deter the average buyer.
The 29 test volunteers all had epilepsy and had implants placed into their brains to establish the cause of their seizures. These patients gave their permission for the researchers to conduct this study.
Furthermore, despite placing electrodes directly on the brain, the music was somewhat distorted due to the quantity of electrodes crammed there. The researchers expect to get even better resolution by increasing the density of electrodes on the brain (number of electrodes/surface area).
Focus on auditory regions for speech reproduction
Despite its current limits in real-world application, scientists have obtained some critical information during this exercise.
Importantly, the researchers were able to determine which areas of the brain respond to various types of stimulation. They discovered that specific parts of the superior temporal gyrus, which is located slightly below and above the ear and is related to auditory processing, respond to the commencement of speech, while other areas respond to other aspects of the music.
Previously, researchers focused on the motor cortex of the brain, which is connected with movements of the lips and vocal cords, to replicate the acoustics of speech. The new study may point scientists in a different direction.
The study also discovered that music perception required both hemispheres, with a preference for the right.
