Summary: The more a person is able to synchronize to a simple rhythm, the better they synchronize their pupils with those of another person.
Source: Dartmouth College
According to a new study from Dartmouth published in Scientific reports.
Previous work has demonstrated that the pupil dilation patterns of speakers and listeners synchronize spontaneously, illustrating shared attention. The team sought to understand how the tendency to synchronize in this way can vary at the individual level and generalize across contexts, as it has been widely debated whether one form of synchrony has a relationship to another.
“We were quite surprised to find that the way your pupils expand and contract to something as simple as a rhythmic beat would predict how well you attend the same way as another person,” explains the lead author Sophie Wohltjen, who was a graduate student in psychological and brain sciences at Dartmouth at the time of the study and is now a postdoctoral fellow at the University of Wisconsin-Madison.
“What this suggests is that there may be some sort of underlying mechanism that may unite many different ways of talking about synchrony.”
The research included two studies. In the first study, individuals listened to a series of tones and were asked which one was softer than the others while their students’ responses were tracked.
Each individual performed this “bizarre detection task” in nine separate sessions that took place on a different day and time for each session. The researchers found a stable, individual-specific variation in the amount trained by each bizarrely paced person.
Some people’s pupils dilated strongly in time with the rhythm, others less so, and as strongly as a synchronized person one day predicted how well they would synchronize the next.
In the second study, 82 people completed the bizarre task once and also listened to audio recordings of four emotional stories while their students’ responses were tracked. The storytellers’ pupil dilations were recorded earlier when they read the stories.
The researchers calculated the pupillary synchrony between the storyteller and the listener, then compared this synchrony to the strength with which the listener synchronized to the rhythmic rhythm of the bizarre task.
The results show that the more a person was trained in the rhythm of the task, the more likely they were to synchronize their students with those of the storyteller. As these individuals could not see the storyteller, the pupillary synchrony could not be explained as simple visual mimicry. Instead, this synchrony was proof that storyteller and listener were witnessing the story in the same way.
“To identify that these two forms of synchrony—simple metronomic entrainment and complex divided attention—are related is really interesting, because it opens up all sorts of larger questions about why this tendency to synchronize varies from person to person. other,” says lead author Thalia Wheatley, Lincoln Filene Professor of Human Relations and director of the Consortium for Interacting Minds at Dartmouth.
“Do musicians more easily synchronize their attention with others? Why are some people super-synchronizing while others are unable to completely synchronize? Do strong synchronizers find it easier to click with others? These are all questions we plan to explore further,” says Wheatley.
“This simple measure of the ability to train to a rhythm could have clinical implications for autism and other disorders, which not only relate to difficulties in social interaction, but also timing,” adds Wheatley.
The research into synchrony with a rhythm builds on the team’s previous work, which finds that the making and breaking of eye contact is linked to fluctuations in pupillary synchrony between conversational partners and makes conversation more engaging.
About this neuroscience research news
Author: Amy Olson
Source: Dartmouth College
Contact: Amy Olson – Dartmouth College
Picture: Image is in public domain
Original research: Free access.
“Synchrony with a Rhythm Predicts Synchrony with Other Minds” by Sophie Wohltjen et al. Scientific reports
Synchronization with a Rhythm Predicts Synchronization with Other Spirits
Synchrony has been used to describe simple beat entrainment as well as correlated mental processes between people, leading some to wonder if the term confuses separate phenomena.
Here, we ask whether simple synchrony (beat entrainment) predicts more complex attentional synchrony consistent with a common mechanism.
While following the eyes, participants listened for evenly spaced tones and indicated changes in volume. Across multiple sessions, we found a reliable individual difference: some people captured their attention more than others, as evidenced by rate-adapted pupil dilations that predicted performance.
In a second study, eye-tracked participants completed the beat task and then listened to a storyteller, which had been previously recorded while they were eye-tracked. An individual’s tendency to train to a rhythm predicted the strength of synchronization of his pupils with those of the storyteller, a corollary of divided attention.
Synchronization tendency is a stable individual difference that predicts attentional synchrony across contexts and complexity.