Search Here

It starts with a chuckle, then the next second, one finds themselves laughing uncontrollably, only because their friend started to. Why does this happen?

Much like yawning, smiling and laughter are contagious, and it works because of the brain's mirror neuron system. Neurons in the brain become active when one person observes another's actions. Instinctively, humans will mimic what they see, which is why babies learn from example.

Sociability: Laughter before language

In a study from 2017, social laughter was linked to endorphin release in specific regions of the brain. Participants of the study who observed friends laughing showed an increase in endorphin release in various parts of the brain, which correlated with more opioid receptors and a higher chance of susceptibility to contagious laughter. The researchers explained that the release of endorphins could be related to the sense of safety, which improves social bonds.

This factor of sociability can be related to an earlier report, where neuroscientist Sophie Scott explained how some scientists believe that laughter could be older than language, which meant that ancestors might have communicated through laughter.

Less contagion: Risk for psychopathy?

On the other hand, another study explored how boys at risk for psychopathy responded to laughter. Researchers found that boys with disruptive behavior and callous-unemotional traits were less likely to engage in social laughter. They alsho showed reduced activity in parts of the brain linked to emotional response. 

However, the researchers said that the results did not necessarily predict antisocial behavior. Further studies need to be done to be able to provide effective intervention methods for various antisocail and psychopahy cases in adolescents.