Laughing is also infected

If you see two people laughing at a certain story, chances are you will smile too, even if you're not aware of this. A new study has confirmed that laughter is also infected.

"It seems that this statement is true: Smile and the world will laugh at you," said Sophie Scott, a neuroscience scientist at the University of London. "We already know that when talking to someone, people often reproduce their behavior, use the right words they use and imitate the gesture. Now we have found the same thing in laughter." .

The team found that the human brain reacted to the sound of laughter and pushed the facial muscles into engaging play. In the study, Scott and colleagues gave volunteers a variety of sounds and measured brain reactions using magnetic resonance imaging. Some positive sounds like laughing or shouting, some negative like screaming or vomiting.

The results show that all sounds cause a reaction in the pre-motor cortex - which functions to make the facial muscles move accordingly to the sound. Respond more clearly to positive sounds - proving they are more contagious than negative sounds. This also explains why we laugh outside intentionally when we see others laugh.

The group also examined facial muscles and found that people often smiled when they heard laughter, but did not show a grimace when hearing the sound of vomiting. This is because people tend to avoid negative emotions and sounds.

Infection of positive emotions can be an important social factor. Some scientists argue that human ancestors laughed together before speaking and laughter could be a precursor to language.

"We often encounter positive emotions, such as laughing or shouting, in collective situations, such as watching comedies or watching football with friends ," Scott said. "This brain reaction - automatically pushing us to smile or laughter, is a way to simulate other people's behavior, help us communicate more easily. It also plays an important role in setting establish relationships in the collective ".

Scott and his colleagues will continue to explore these emotional responses in people with autism, which are poor in social interaction and emotional handling - to understand more about the disease.

MT