If a great singer seems to light up your mind, it’s not your imagination.
Researchers at Massachusetts Institute of Technology (MIT) have identified a group of neurons in the brain that react to singing but not to other types of music.
“This was a finding we really didn’t expect, so it very much justifies the whole point of the approach, which is to reveal potentially novel things you might not think to look for,” said lead author Sam Norman-Haignere. He is a former MIT postdoctoral researcher who is now an assistant professor of neuroscience at University of Rochester Medical Center, in New York.
Norman-Haignere and his team said the neurons respond to the specific combo of voice and music, but not to instrumental music or regular speech. The song-specific hotspot is located at the top of the temporal lobe, near brain areas involved in music and language.
The location suggests that these neurons may respond to singing-related features such as perceived pitch, or the interaction between words and perceived pitch, before relaying information to other parts of the brain for more processing.
This is the first study to identify these neurons, and more research is needed to determine exactly what these singing-specific neurons are doing, according to the authors of the paper published Feb. 22 in Current Biology.
The researchers had previously used functional MRI (fMRI) to identify a population of neurons in the brain’s auditory cortex that responds specifically to music.
In this new study, the investigators used recordings of electrical activity taken at the surface of the brain as 15 volunteers heard the same 165 sounds used in the previous study.
The newly identified neurons had very weak responses to either speech or instrumental music, showing that they’re distinct from the music- and speech-selective neurons previously identified, according to the researchers.
“There’s one population of neurons that responds to singing, and then very nearby is another population of neurons that responds broadly to lots of music,” Norman-Haignere said in an MIT news release.
“At the scale of fMRI, they’re so close that you can’t disentangle them, but with intracranial recordings, we get additional resolution, and that’s what we believe allowed us to pick them apart,” he explained.
The researchers said they also want to find out whether infants have music-selective brain areas in order to find out when and how they develop.
For more on music and your brain, go to the University of Central Florida.
SOURCE: Massachusetts Institute of Technology, news release, Feb. 22, 2022