How Listening to Live and Pre-Recorded Music Changes Brain Activity
Post by Meredith McCarty
The takeaway
Listening to music is not only an enjoyable and common pastime but has been found to correlate with changes in brain activity in many key regions involved in emotional processing. Live music is found to be more closely correlated with increased activity in key brain networks involved in emotional processing than pre-recorded music.
What's the science?
Music listening evokes strong feelings in listeners and has also been found to correlate with increased activity across the affective brain network which is involved in emotional processing and emotional recognition. Key regions associated with this affective network are the limbic system, most notably including a brain region called the amygdala, which is involved in emotional processing and processing of music-evoked emotions. Because of the influence of music listening on activity in this affective brain network, music can be a powerful tool to help us better understand brain dynamics. This week in PNAS, Trost and colleagues use a novel closed-loop music performance experimental setup in order to better understand the dynamics of music listening in the brain.
How did they do it?
To study how music listening affects brain activity, the researchers designed a novel closed-loop music performance setup, where the musician and the listener are influencing each other in real time. The researchers recruited 27 participants who had no musical experience to listen to different music through in-ear headphones while in a functional magnetic resonance imaging (fMRI) scanner. The fMRI scan captures brain dynamics that are then shown on a screen to a piano performer who can then adjust their playing to try and increase activity in key regions, including the amygdala. The performers were instructed to change the dynamics, density of notes, and articulation of the piece to try and increase activation in the amygdala of the listener.
The musicians performed 12 30-second pieces that varied in their musical features (arousal, valence, and acoustic features). Six pieces were composed to be perceived as “pleasant” and six as “unpleasant”. The key comparison in this study was that participants listened to the same series of musical pieces both live (with real-time feedback to the performer) and pre-recorded (from the same performer, but with no feedback aspect). Live and pre-recorded pieces were both played on the same digital piano connected to headphones; the only ‘live’ aspect of the live music was the use of the participants’ neurofeedback by the performers. Through analyzing changes in brain activation, as well as changes in information flow between regions of the brain, this design allows for the careful study of music perception in the brain, and how differences in music performance change brain activation.
What did they find?
When comparing overall activation in different brain regions, the researchers found that live music significantly increased activity in the amygdala and other music-processing regions when compared with pre-recorded music. This suggests that live music has features that increase emotional music processing in the listener’s brain. In a novel finding, the pulvinar nucleus of the thalamus showed significantly elevated activation in response to live music, suggesting that live music involves higher attentional demands than pre-recorded music.
The directed functional connectivity analysis, which quantifies information flow between regions of the brain, revealed overall increased connectivity between numerous limbic regions for live music more so than pre-recorded music. Live unpleasant music recruited an even larger network of regions than live pleasant music, indicative of greater emotional processing.
When comparing how correlated the musical features of the piano performance were with the listener’s brain dynamics during the real-time feedback condition, the researchers found high correlations for live music and an absence of this correlation in the pre-recorded music condition. Interestingly, the auditory cortex showed the most significant correlation between recorded brain activity and musical features, indicating an important role for this region in emotional information integration.
What's the impact?
This study found that live music consistently elicits higher brain activity in key limbic regions, including the amygdala, relative to pre-recorded music. As the first study to implement a real-time neural feedback design where the performer and the listener influence each other, these results have strong implications for research into how music is processed in the brain.