Biological Synchronization in Social Interaction

During social interactions, even with strangers, our biological signals can synchronize if we like each other and trust each other in the moment. This synchronization includes heart rates and breathing. Emotional contagion, a term often used, is a result of human nervous systems regulating each other because we are social animals. When someone else gets worked up, it is likely to affect and work up the other person too. People who say 'don't be sad or angry' may actually mean that they do not want to deal with those emotions themselves, leading to a desire for the other person to calm down.