Music emphasizes brain synchrony and enhances empathy in music ensemble

Can you imagine a day without music? Probably not. Music permeates every aspect of our lives – parties, rituals, workouts, and even scientific studies. A growing field of research is exploring the connection between music and brain synchrony. This study investigates the brain oscillatory dynamics and synchrony of two persons engaged in a piano duet performance in a hyperscanning setting.

Brain Synchrony EEG

Whether we’re creating it or just listening, music has a profound effect on our brains. But what if we could dive deeper and understand the exact relationship between music and the brain synchrony? This study has done that, utilizing a Hyperscanning EEG technique.

The Motivation Behind the Study

The science of the brain’s response to music has been a hot topic for researchers. The researchers wanted to dig into the mysterious link between our brains and music. Their primary motivation was to understand how two pianists synchronize their performances. In other words, they investigated how their brains “talk” to each other during a duet.

The main hypothesis was that the individual rhythms, in piano duets, influence the partners’ ability to sync up.

The researchers predicted that “syncing” occurs in the brain during the duet, as brainwave activity matches the duet’s pace. They suggested that increased brain activity should connect to better musical timing. Additionally, partners’ brainwaves should mirror each other, reflecting a shared brain rhythm during the duet.

Setting the Stage: Hyperscanning EEG setup

To gain a comprehensive understanding, researchers designed the following setup (depicted in the Figure below). Forty pianists were randomly split into 20 pairs. Each pair was wearing a wireless EEG device SMARTING during the performance. This way the pianists were able to move naturally, giving a more accurate picture of the neural processes.

Two identical digital keyboards, facing each other, were used for the duet experiment. There was a barrier between pianos to avoid visual cues from affecting the performance. Piano Key presses were captured and sent as MIDI data using software.

The data was sent to a computer and synchronized with EEG data via lab streaming layer (LSL) protocol over a local area network (LAN).

Brain synchrony, a Hyperscanning EEG setup with two pianos
The experimental setup and synchronization of (A) MIDI and multiple EEG data over the LSL protocol and (B) Order of experimental tasks

Piano duets

Pianists were randomly paired, and their EEG was recorded in a Hyperscanning setup. This way, the researchers could understand how our brains interact and synchronize during a musical duet.

In duets, partners alternated as the leader, setting the performance pace, rather than following a pre-set rhythm. The study was divided into two phases: the rehearsal and the performance.

During rehearsal, musicians practiced the piece together until they felt ready for the stage. In the performance phase, they played spontaneously, mimicking the unpredictability and creativity that characterizes a live performance.

The Harmony of Findings: Results from the Study

The researchers found that the pianists’ ability to synchronize their performances was connected to their individual spontaneous performance rates. Partners who had greater differences in spontaneous performance rates showed larger asynchronies, suggesting that their performances were less synchronized.

These findings align with theories that predict period coupling between oscillations as function of difference in their natural frequencies (like brain activities).

What effect does music have on a brain synchrony?

The study shows that music triggers oscillatory processes within and between the performers’ EEG. These processes play a significant role in how the performers synchronize their actions. Furthermore, the research suggested that synchronization accuracy is tied to leadership behavior.

An interesting aspect of the research is the phenomenon of amplitude envelope coupling. This is where the pianists’ brainwave patterns fluctuate in harmony throughout the performance. It is suggested that this could be a distinctive auditory-motor pattern unique to each performance.

EEG spectral power was analysed to understand brain activity during different roles as Leader or Follower. The findings, depicted in Figure below, showed a peak in spectral power at the Duet Performance Rate. This peak was stable across musical roles, showing no significant change between Leaders and Followers.

The spectral power was notably higher at the Duet performance rate than surrounding frequencies, with the power being maximal at fronto-central sites. These areas are often associated with auditory-motor perception and production.

Brain synchrony showed through the mean power spectra.
Top panel: Noise-normalized power spectra from a sample pair of duet pianists for First-Leader (solid lines) and Second-Leader conditions (dashed lines); Bottom panel: Mean power spectra centered at the frequency of each Duet performance, shown for each pair in thin gray lines and grand average across pairs in blue for auditory-motor channels (FC1, FC2, Fz and Cz)

Corelation between duets synchronization accuracy and PSD

a correlation was found between the synchronization accuracy of the Duet pairs and spectral power. Leaders who had larger Power Spectral Density (PSD) values were found to have smaller Duet asynchrony. There was also a sign of similarity in amplitude fluctuations across the time series within each Duet condition.

Relationship between brain synchrony and empathy

Interbrain synchrony was also found to correlate with the degree of empathy. Empathy is a trait tied to understanding and sharing feelings with others. The musicians weren’t just creating music together. They were also building a shared emotional experience.

Difference in brain synchrony during Rehearsal and Performance

The EEG patterns differed between the rehearsal and performance phases.

During rehearsal, pianists focus on technical accuracy. Their brain activity displayed a specific pattern linked to attention and cognitive control. Yet, during the performance, a different pattern emerged. The pattern associates with creativity, improvisation and music perception.

This change offers insight into how the brain switches between practice and actual performance.

Making Sense of the Symphony: The Connection Between Music and the Brain

This pioneering research offers valuable insights into the neuroscience of music performance. By highlighting the links between spontaneous performance rates, synchronization, and brain synchrony. The study has deepened our understanding of connection between music and the brain.

The results underline the incredible capabilities of the human brain and its reaction to music. It’s evident that music isn’t just a form of entertainment. It’s a powerful tool that can stimulate our brains in ways we’re only beginning to understand.

The researchers’ exploration into the world of brain synchrony and music performance serves as a stepping stone for future studies. Music is more than a universal language. It’s a universal stimulus, resonating deep within our neural pathways and shaping our cognition.

The original publication source: https://www.frontiersin.org/articles/10.3389/fnhum.2021.717810/full

Recommended reading