Their heartbeats appear to speed up or slow down at the same points during the story.

We have known for some time that under certain circumstances people attune some bodily mechanisms to each other. For example, research has shown that the hearts of lovers beat at the same speed. We also know that bodily functions such as heart rate or breathing often synchronize when people share an experience. “The starting point here is that you have a bond with each other and are physically present in the same place,” says researcher Lucas Parra. “What we have discovered, however, is that the phenomenon is much broader.”

Heartbeat

An new study has shown that even when people listen intently to a story together, their hearts start beating in sync. Their heartbeats appear to speed up or slow down at the same points during the story. “So simply listening to a story can cause similar heart rate fluctuations,” says Parra. “It’s the cognitive function that drives your heart rate up or down.”

When people listen to the same story, they unconsciously synchronize their heartbeats with the story – and therefore with each other. Image: Perez and Madsen et al.

However, the condition is that people listen attentively. Because various experiments show that the heartbeats of test subjects only synchronized when they showed interest. “What’s important is that the listener pays attention to the story,” emphasizes researcher Jacobo Sitt. “It’s not about emotions, it’s about being involved and attentive and thinking about what’s going to happen. Your heart responds to those signals from the brain.”

Listen

The researchers conducted a series of experiments to investigate the role of consciousness and attention in the synchronization of participants’ heartbeats. In the first experiment, the subjects listened to an audiobook while their heart rate was monitored using an electrocardiogram. The researchers found that the participants’ heart rates changed based on what happened in the story. At the same points throughout the story, the heartbeat accelerated or slowed down.

Instructional Videos

Even while watching short, boring instructional videos, heartbeats seem to synchronize. For example, the researchers observed similar fluctuations in the test subjects. And that while these videos were purely educational. This shows that emotion is not an advantage for the synchronization of heartbeats. However, this experiment shows that attention is important. When the subjects were asked to count backwards in their heads while watching the video, this lack of attention resulted in unevenly beating hearts.

Breathing
Incidentally, the participants’ breathing does not appear to synchronize while listening to stories or watching videos. And that’s quite surprising. It is known that breathing influences the heart rate. Yet the participants each breathe in and out at their own pace.

According to the researchers, the results from this study are not only interesting facts, they could also clarify things about the connection between the brain and the body. “Neuroscience increasingly sees the brain as part of an anatomical, physical body,” Parra says. “This research is a step toward taking a broader view of the brain-body connection and how the brain affects the body.”