Do Our Brains Sync Up With Others When We Listen to the Same Song?
Image Source: MRI Audio
If you and your friend are listening to the same Coldplay song for the first time, your brains might respond very similarly. But interestingly, the more times you hear the song, the less alike your brain activity might look.
A recent study published in the journal Cortex by Sternin et al. investigated this phenomenon during the COVID-19 pandemic. Using functional magnetic resonance imaging (fMRI), the researchers were able to measure brain responses when participants listened to familiar versus new music. Through this, the study was able to see how closely human brain activities sync up to the same parts of a new song, and how that changes with more exposure to that song. This activity was seen in both younger and older adults.
The authors introduced a term that is important to understand. Intersubject synchrony sounds complex, but it simply describes how similarly human brains react when experiencing the same thing. For example, if you and your friends are watching a movie for the first time, most of your brains will show similar activity at the same moments, whether it is a horror movie jump scare or a funny joke. But Sternin et al. wanted to take this notion further and determine whether this shared brain activity is stronger the more we hear the same thing over and over again. The researchers tested this by having younger and older adults listen to short audio clips of various original songs.
When in the fMRI scanner, participants passively listened to the songs and researchers kept track of how many times they heard it. Participants were also told to listen to it multiple times per week.
As time went on, the researchers wanted to test how familiar they had become with the song. First, they asked participants questions about the lyrics of the song. Second, they listened to 2 seconds of the song to see if they recognized it.
Contrary to their original prediction, the researchers found that participants did not demonstrate intersubject synchrony the more times they heard the song. Rather, there was more synchronization of brain activity to new stimuli in comparison to familiar stimuli, regardless of how familiar it had been.
The researchers were also able to pinpoint the parts of the brain that had shared synchrony. In younger adults, synchrony between participants’ brains was observed in their temporal lobes, the parts of your brain necessary for processing auditory information, and the frontal orbital cortex, which is involved in a wide range of decision-making processes. In older adults, this was only seen in the temporal lobes. This suggests that the parts of your brain involved in understanding sound and making decisions are both important for shared brain responses across people.
Overall, the study helped the researchers get one step closer to understanding the effects of repeated exposure on synchrony. Researchers believe there are multiple reasons and experiences that might be shaping how we process things we already know. Our brains are more alike when we experience something together.
Featured article: Avital Sternin, Lucy M. McGarry, Bobby Stojanoski, Jessica A. Grahn, Adrian M. Owen. The effect of repetition on intersubject synchrony assessed with fMRI, Cortex, Volume 167, 2023, Pages 51-64, ISSN 0010-9452, https://doi.org/10.1016/j.cortex.2023.05.020.