We’ve all been there before. One person tells a joke that you might not think is particularly funny, or something happens that causes one person around you to laugh. That person begins laughing, and they don’t stop. Next thing you know, another person around you is laughing, and then another until you find yourself laughing along.
But why do we laugh when others are laughing? Is laughter really contagious?
The Brain Responds Directly to Laughter

According to a recent study from Live Science, laughter truly is contagious. As the study explains, the brain quite literally responds to the sound of laughter by moving one’s facial muscles into the form of a smile in response.
Positive Sounds are More Contagious than the Negative
The same study also confirmed that the brain tends to react to all sorts of social sound patterns similarly. However, this phenomenon is much more prevalent in positive situations, such as laughter. The study attributes this to a direct effort to avoid negative sounds and reactions like not wanting to cry when others are crying. But when it comes to laughter, people are much more susceptible to letting it catch on.
A Face of Socialization

A separate study published in the Proceedings of the National Academy of Sciences cites this phenomenon as a direct reaction to attempted socialization. This is because humans often want to demonstrate a direct response to other people’s emotions to strengthen the bond between them. While this is likely all happening subconsciously, it occurs to bring people together quite literally by causing them to laugh together.
Lack of this Response Linked to Mental Disorders
If you often find yourself laughing along with those around you, feel assured that your brain is working the way it’s intended to.
According to that same study, because this trait is linked to proper socialization, those who do not innately demonstrate this response may be suffering from a mental disorder. Lack of connectedness and appropriate emotional responses may be directly related to social disorders.
Contagious Laughter Operates Like Contagious Smiles

According to both studies, the same receptor allows one to laugh continuously as to smile continuously. People who want to feel closer to others will often repeat the laughter of those around them while also mirroring their smiles.
Contagious Laughing Fits
It is likely the exact reason pairs or groups of friends often find themselves in echoed laughing fits. If one person starts laughing and another begins to laugh with them, the two would probably continue laughing to continue demonstrating this response with one another. The laughter may sustain itself for a long while, with the entire group building off the energy of one another.
Laugh and the Whole World Laughs With You
It seems that both studies have found that laughter is truly contagious, making the old axiom “laugh and the whole world laughs with you” ring true. The next time you want to try lightening the mood in a room, why not try making yourself laugh? It is likely others will laugh right along with you.