THE ESSENTIAL
- Singing is different from speech and instrumental music, so different neurons are involved.
- Vocal melodies, compared to instrumental ones, are better memorized by humans.
For several years, music has been used by doctors for therapeutic purposes, so this means that melodies produce effects on our neural system. But, according to a new study published in the journal Current Biology, another art form, very close, might also have a different impact on our brain: singing. During their work, the researchers wanted to identify the neurons that were specifically concerned with singing, because they had already, duringa previous studyidentified those responding to music in general.
Two methods combined to identify neurons
To go further, the researchers this time combined two methods. First of all, that which makes it possible to identify neuronal populations from functional magnetic resonance imaging (fMRI) data. They had already used it in their first study. These fMRIs make it possible to see the reaction of hundreds of thousands or millions of neurons because they use a very small unit of measurement. Then they paired it with higher-resolution data obtained by electrocorticography (ECoG). “This way of combining ECoG and fMRI is a significant methodological advance. Combining the improved resolution of ECoG with data from fMRI allows for better localization of global responses” in the brain, said Josh McDermott, one of the study’s authors in a statement. A total of 15 patients participated in this clinical trial. The researchers analyzed the data and were thus able to identify the neurons that specifically reacted to the song.
The neurons of music and singing very close
Singing-specific neurons are located in the auditory cortex at the top of the temporal lobe, near regions selective for language and music. “There’s a population of neurons that responds to singing and another nearby that responds more broadly to music. On the fMRI scale, they’re so close you can’t identify them, but with ECoGs, we get extra resolution, and that’s what we think allowed us to tell them apart.”explained Sam Norman-Haignere, one of the authors.
In detail, the researchers discovered that the information relating to the song must first be processed by the primary auditory areas and then be sent to those sensitive to the song. This path therefore involves a certain time to arrive in the right processing areas of the brain, which is not the case with speech. In the future, the scientists plan to continue their research, in particular to determine whether infants also have specific areas for music and singing.