When people listen to stories, they subconsciously synchronise their heart rates with the narrative — and, therefore, each other — a study has demonstrated.
The finding builds on previous studies that found that people often sync up bodily functions like heartbeats or breathing when undergoing a shared experience.
Experts led from the Paris Brain Institute found a similar phenomenon occurs even when people are listening to a story on their own, as long as they pay attention.
The finding could help to develop a new and easy-to-administer hospital test to determine the level of a given patient’s consciousness.
When people listen to stories, they subconsciously synchronise their heart rates with the narrative — and, therefore, each other — a study has demonstrated
Your heart rate explained
Your heart rate is the number of times your heart beats per minute (bpm).
A normal heart rate is between 60 and 100 bpm while you’re resting.
However, it will vary depending on when it’s measured and what you were doing immediately before the reading.
Your target heart rate (THR) is between 50% and 70% of your maximum heart rate.
You should aim to exercise with your heart rate between these two figures.
Your target heart rate will make sure you increase your fitness and strength safely.
‘There’s a lot of literature demonstrating that people synchronize their physiology with each other,’ said paper author and biomedical engineer Lucas Parra of the City College of New York.
However, he explained, usually ‘the premise is that somehow you’re interacting and physically present the same place.’
‘What we have found is that the phenomenon is much broader, and that simply following a story and processing stimulus will cause similar fluctuations in people’s heart rates,’ he added.
‘It’s the cognitive function that drives your heart rate up or down.’
‘What’s important is that the listener is paying attention to the actions in the story,’ added fellow paper author and neuroscientist Jacobo Sitt of the Paris Brain Institute.
‘It’s not about emotions, but about being engaged and attentive, and thinking about what will happen next. Your heart responds to those signals from the brain.’
In their study, the team conducted a series of four experiments, all of which involved participants following along with an audio story or video while their heart rate was measured using an electrocardiogram.
For the first test, 27 adults listened to a 16-minute excerpt from the opening of Jules Verne’s 1870 science fiction adventure, ‘Twenty Thousand Leagues Under the Seas’.
‘The text is relatively suspenseful as it describes reports of an unknown monster that destroys ships,’ the researchers noted in their paper.
Based on the electrocardiogram readings, the team found that subjects’ heart rates changed based on what was happening in the narrative, with most experiencing increases and decreases in heart rate at the same points in the tale.
The next experiment involved five instructional videos which, unlike the audiobook excerpt, had no underlying emotional variation, allowing the team to show that emotional engagement with the story did not play a role in the synchronisation.
The finding builds on previous studies that found that people often sync up bodily functions like heartbeats or breathing when undergoing a shared experience. Experts led from the Paris Brain Institute found a similar phenomenon occurs even when people are listening to a story on their own — as long as they pay attention
Playing the clips to 27 students from the City College of New York, the researchers found once again that the subjects’ heart rates showed similar fluctuations as they watched the video.
The clips were then played again, but this time the participants were asked to watch the videos while counting backwards in their heads from a starting number between 800–1,000 in steps of seven.
This led to a decrease in the synchronisation between heart rate and video across all the subjects, indicating that attention must play an important role.
Building on this, the third test saw 21 adults asked to recall facts from a series of short children’s stories, some of which they were allowed to listen to attentively and some of which they were distracted by the researchers.
The team found that the more synchronised the participants’ heart beats were with the narrative, the more likely they were to be able to accurately recall the details.
This, the researchers said, demonstrates that the changes in heart rate are as signal of the conscious processing of the narrative.
The finding could help to develop a new and easy administer hospital test to determine the level of a given patient’s consciousness. Pictured: a hospital patient in a coma
In their final experiment, the researchers recruited 19 patients suffering from disorders of consciousness, such as being in a coma, or a persistent vegetative states, and compared them with 24 healthy control subjects.
As with the previous test, each participant was played a a children’s audio story.
The team found that, as anticipated, the patients had lower rates of synchronisation than the healthy subjects who were better able to follow along with the narrative, but also that some of the patients who showed higher levels of synchronisation went on to regain some consciousness in the following six months.
Based on the findings, the researchers propose that such a test could be used to easily assess a patient’s state of consciousness.
‘This study is still very preliminary, but you can imagine this being an easy test that could be implemented to measure brain function,’ said Professor Sitt.
‘It doesn’t require a lot of equipment. It even could be performed in an ambulance on the way to the hospital.’
However, the neuroscientist added, further tests with larger numbers of patients will be needed to verify the results, alongside comparisons to scans of brain function such as can be produced with electroencephalogram and functional MRI machines.
According to Professor Parra, research like this is important for understanding such topics as the brain–body connection and mindfulness.
‘Neuroscience is opening up in terms of thinking of the brain as part of an actual anatomical, physical body,’ he explained.
‘This research is a step in the direction of looking at the brain-body connection more broadly, in terms of how the brain affects the body.’
The full findings of the study were published in the journal Cell Reports.
The human ‘mind meld’: Our brains synchronize when we converse with another person
Having a conversation causes the brains of the participants to begin to work simultaneously, researchers have found.
Researchers analysed the brain activity of two strangers who had a conversation for the first time, finding that the movement of their brain waves took place at the same time.
This pattern is so significant that the researchers were able to find out if two people were having a conversation solely by analysing their brain wave.
The findings could have applications for cases where people have difficulties with communication.
The study , conducted by researchers at the Basque Centre on Cognition, Brain and Language (BCBL), confirmed by recording brain activity that the neuronal activity of two people involved in an act of communication ‘synchronise’ in order to allow for ‘connection’ between both subjects.
‘It involves interbrain communion that goes beyond language itself and may constitute a key factor in interpersonal relations and the understanding of language,’ Jon Andoni Duñabeitia, a co-author of the study, told SINC .
The rhythms of the brainwaves corresponding to the speaker and listener adjust according to the physical properties of the sound of the verbal messages expressed in a conversation.
‘The brains of the two people are brought together thanks to language, and communication creates links between people that go far beyond what we can perceive from the outside,’ said Dr Duñabeitia
‘We can find out if two people are having a conversation solely by analysing their brain waves.’
To conduct the study, the researchers analysed the brain waves of 15 pairs of people of the same sex, where complete strangers to each other an were separated by a folding screen.
This was to ensure that the connection generated was actually due to communication that was established.
They used a technique called electroencephalography (EEG) which measures the electrical activity in the brain.
It’s a non-invasive procedure that uses flat metal disc electrodes attached to the scalp.
To be able to know if two people are talking between themselves, and even what they are talking about, based solely on their brain activity is something truly marvellous,’ said Dr Duñabeitia.
‘Now we can explore new applications, which are highly useful in special communicative contexts, such as the case of people who have difficulties with communication.’
The researchers say that in the future, the understanding of this interaction between two brains could allow for analysis of complex aspects of the fields of psychology, sociology, psychiatry, or education.
‘Demonstrating the existence of neural synchrony between two people involved in a conversation has only been the first step’ said Dr Alejandro Pérez, a co-author of the study.
‘There are many unanswered questions and challenges left to resolve.’
Dr Pérez also says that the practical potential of the study is huge.
‘Problems with communication occur every day, said Dr Pérez.
‘We are planning to get the most out of this discovery of interbrain synchronisation with the goal of improving communication.’
As a next step, the researcher plan to apply the same technique and pair dynamic to see if the brains of two people ‘synchronise’ in the same way when the conversation takes place in their non-native language.