Today, music is as integral to society as culture is, as t has been ingrained in humanity's history across thousands of years. However, one question yet remains: how exactly do each one of our brains process it?
This is what researchers at UC San Fransisco endeavored to answer, through a study where they accurately mapped which parts of the brain are actively being used when listening to music.
Findings of the Study on the Brain's Melody Processing
What they figured out is that the brain is focused on simultaneously figuring out two things at once during the listening process: the pitch of a note itself and the most suitable extension of the melody.
The study, which was published last Feb. 16 in the "Science Advances" journal, also led to a clarification in regards to which neurons are responsible for processing melodies, a question that has left researchers stumped for years.
"We found that some of how we understand a melody is entwined with how we understand speech, while other important aspects of music stand alone," said Edward Chang, MD, one of the study's proponents and member of UCSF's Weill Institute for Neurosciences.
According to Chang, the first two groups of neurons have already been identified in a prior 2017 study, in which Chang was also involved. These particular chunks of neurons mainly focus on processing vocal pitch and extracting emotional meaning from speech.
The breakthrough, however, is with the third group which is only used when predicting musical melodies and is entirely separate from speech-processing neurons.
A Separate Part of the Brain is Used for Melodic Guesswork
Chang and his team said that even though this process is unique only to music processing, a similar set of specialized neurons are delegated to a specific "guessing" action realized during speaking. The researchers likened this unique process to the "auto-correct" function of smartphones.
Because of this, Chang and his colleagues knew what to look for, as they theorized that such specialized neurons should similarly exist for processing music.
They tested this hypothesis by recording the brain activity of eight volunteers, all of whom were undergoing their surgical workup for epilepsy, while they were listening to different melodic passages from Western music.
To account for the study's control, the participants also listened to passages of spoken English, and its hypothesis was proven to be accurate.
The data showed that the same group of neurons was being used in both the processing of pitch and speech, however, when it comes to predicting what new melodic note would come next or what word would follow in a sentence, each of the processes had dedicated groups of neurons.
"When we're listening to music, two things are happening simultaneously," explained Chang. "There's a low-level processing of the individual notes of the melody, and then this high-level, abstract processing of the context of these notes."
