Study: lovers synchronise on a brain level more strongly than friends do
Researchers from China have found that brain activity of lovers is more synchronised than that of close friends.
This discovery demonstrates that relationships between romantic partners and friends have different neural mechanisms, which is reflected not only in behaviour but also in brain function.
These findings were published in the scientific journal NeuroImage.
The experiment involved 50 couples: half of them were heterosexual romantic partners and the other half were opposite-sex friends. The length of each couple's relationship ranged from three months to three years, and all were considered close enough to participate in the study.
Participants in the experiment watched videos lasting between 50 and 250 seconds that evoked a variety of emotions - happiness, sadness, fear, disgust and anger. During the viewing, scientists used EEG hyperscanning to monitor the brain activity of both participants in the pair at the same time, which allowed them to assess their neural synchronisation. After each video, the participants gave their subjective ratings of their emotional response to the video.
The results showed that romantic couples had higher brain activity synchronisation than friends, especially during moments of processing strong emotions. More interestingly, couples with lower relationship quality showed higher synchronisation of brain activity in the prefrontal cortex, while those who rated their relationships as more harmonious had better behavioural synchronisation.
One of the study authors noted: We were surprised that relationship quality was negatively correlated with prefrontal synchronisation. This may suggest compensatory mechanisms where couples with poor relationship quality increase brain activity to maintain emotional connection.
Particularly strong synchronisation was found when processing negative emotions such as anger and sadness, whereas this phenomenon was less pronounced for positive emotions such as joy. Researchers suggest that such findings may require further validation in more diverse samples, as the study involved mostly people with high levels of education.
Ultimately , the study confirms that love and friendship are two different types of relationships that fulfil different functions and involve different neural mechanisms. Even if friends seem very close, their relationship cannot compare to that between lovers.