 Welcome to Spotlight. I'm Colin Lovre. And I'm Liz Wade. Spotlight uses a special English method of broadcasting. It is easier for people to understand, no matter where in the world they live. Today's Spotlight is on laughter. Lord Byron was an English poet who lived 200 years ago. He said, Always laugh when you can. It is cheap medicine. Charles Dickens was a famous English writer in the 19th century. In his book, A Christmas Carol, he said, There is nothing in the world so infectious as laughter and good humor. Martin Luther King Jr. was a leader in the U.S. Civil Rights Movement in the 1960s. He said, It is cheerful to God when you rejoice or laugh from the bottom of your heart. At about the same time, Audrey Hepburn was a Hollywood film actor. She said, I love people who make me laugh. I honestly think laughing is the thing I like most. It cures a lot of problems. It is probably the most important thing in a person. These people describe laughter as a medicine, an infection, praise to God, and the thing they like most. How can it be all these things? We often laugh at jokes and funny stories, but scientists have studied laughter. They tell us that laughter is about far more than jokes and funny stories. Professor Robert Provine is a neuroscientist at the University of Maryland in the United States. He discovered that we are 30 times more likely to laugh when we are with other people. He said that laughter is a signal we send to other people. It is a sort of language. If we are alone, laughter almost disappears. In the web journal Psychology Today, he explains, Laughter is mainly a social voice that joins people together. It is a hidden language that we all speak. It is not a learned group reaction. It is a natural behavior. Professor Sophie Scott is a neuroscientist, too. She works in the United Kingdom at University College London. She is also a part-time comedian. She tells jokes to audiences. She wrote for the BBC about how this laughing language works. When we talk with our friends, we laugh at their comments. The comments may not even be funny, but we show our friends that we like them and agree with them by laughing. She writes, The science of laughter is telling us that laughter is less to do with jokes and more a social behavior. We use it to show people that we like them and that we understand them. So we all speak the language of laughter and we all recognize laughter. But people in different cultures use humor and laughter in different ways. People in one culture may find something funny, but people in another culture may not find the same thing funny. And people in different cultures do not always agree when it is correct behavior to laugh. People in the United Kingdom and the United States may use humor in a business meeting. But people from Germany or Japan would not usually do this. People can also catch laughter. For example, one friend will start to laugh, then another joins in, and then another, and another. You may have experienced this. Earlier we heard that Charles Dickens said that laughter is infectious. This makes laughter sound like a disease. In fact, in an incident from 1962, laughter seemed like a virus. In that year, three girls started to laugh at their school in Tanzania. They could not stop laughing. More girls started to laugh. Six weeks later, 95 girls were laughing and could not stop. The school had to close. The laughing spread to other schools and villages. By the end of the incident, about 1,000 people had been affected. But for most people, laughing is not a problem. As Lord Byron suggested, laughter can be like a medicine. Many researchers have studied how laughter has the power to reduce pain. In one study, researchers tested how long people could suffer pain. They did this by putting something frozen on people's arms. Half of the group watched something funny. The other half watched something neutral. The researchers found that people who had watched something funny increased the time they could suffer pain. Professor Robin Dunbar of Oxford University led this research. He believes that when we have great big laughs, the body releases natural chemicals called endorphins. These chemicals act as painkillers. Other experts have suggested that laughing makes us think about other things than the pain. Or laughing makes muscles relax, so they are not painful anymore. Many scientific studies show that humour also has a positive effect on the immune system. This is the system that defends a body from infections. Paul McGee is an expert who writes and speaks about laughter in the United States. He advises building more laughter into your life helps you to have all the natural healing resources of your body ready for use. Other experts believe that laughter may even help prevent heart disease. Michael Miller is the director of the Center for Preventative Cardiology at the University of Maryland in the United States. He has been involved in research in this area. He says the recommendation for a healthy heart may one day be exercise, eat right and laugh a few times a day. You may now think of laughter as being like medicine, but could it be medicine for a nation too? In South Sudan, the United Nations mission in South Sudan even tried to use laughter as a way to help heal a nation. South Sudan has suffered from a civil war. In 2016, South Sudan held a festival called Let Us Laugh. During the event, comedians told jokes about politics and life. A U.N. press release about the event told about Tong Tong. He is a student in South Sudan. He explained why the event was so important. This is good for South Sudan. It is the way to go for peace. Laughing together is good because if we can all laugh together at the same things, it will be harder to see each other as enemies. We can be friends instead of fighting each other. What makes you laugh? Has laughing ever helped you? Tell us what you think on our website or email us at radio at radioenglish.net. You can also comment on Facebook at facebook.com slash spotlight radio. The writer of this program was Katie Blake. The producer was Bruce Gulland. The voices you heard were from the United Kingdom and the United States. All quotes were adapted for this program and voiced by Spotlight. You can listen to this program again and read it on the internet at www.radioenglish.net. This program is called A Good Laugh. Look for our listening app in the Google Play Store and in iTunes. We hope you can join us again for the next Spotlight program. Goodbye.