 Maybe you're not as funny as you think you are. Picture this. You're watching TV alone and you see a celebrity you don't like make a joke. You don't laugh. Your best friend, however, tells you the exact same joke to your friend group years later and now it's the funniest joke in the world. Why is this? Contrary to what you may believe, laughter is not solely dependent on how objectively funny a joke is. Neuroscientist Sophie Scott says that most laughter is due to social circumstances. She believes that we don't laugh at jokes, but we laugh to show others we understand them, agree with them, and that we like them. This explains why we are more likely to laugh at a friend than a stranger. Research suggests that the younger you are, the more contagious laughter is. As you get older, laughter becomes less contagious. This could be because older people understand laughter better. Older people are more likely to tell the difference between posed and real laughter because of past experience. Therefore, they don't feel the need to respond with laughter when they see it. Looking to science, in 2007, an FMRI scanner measured how volunteers' brains responded to a range of sounds. These sounds were either positive, like laughter, or negative, like screaming. The sounds encouraged a reaction in the premotor cortical region of their brains, which is the area that encourages facial muscles to move. The highest response was for positive sounds, giving us insight into why we laugh when we hear someone tell a joke. Certain research suggests that laughter was used as a forerunner to language by our ancestors to show that they meant no harm. In other words, laughter was not used to benefit us, but rather as a means of being accepted by potential threats. In 1974, a study showed that people were more likely to find jokes funny when in a group. This could explain why we find pleasure when watching movies. The characters are relatable, and we feel like we know them. The question then arises. Can contagious laughter benefit us? Robert Wellington conducted a longitudinal study on stressful conversations with couples. He found that couples who laughed during their stress made each other feel better. This shows how laughing together can be relaxing and can bring couples together. Studies have also shown that embarrassing situations can be lessened by laughter. If your friend falls over and you respond by laughing, provided that they are not seriously hurt, then they might start laughing too. Laughing at yourself can help reduce your humiliation and prevent an entire loss of dignity. A laughter epidemic happened on the 30th of January 1962 in a boarding school in Tanganyika, where three young girls began giggling at a joke. Their laughter spread throughout 95 of the 159 students who spread it to their parents once they left. One child laughed for 16 days straight. The school was closed temporarily as it spread to home villages, affecting hundreds of people. The cause of this was theorized to be mass hysteria or mass psychogenetic illness. The incident was stress-induced, supposedly due to the fact that Tanganyika had just won independence and students were suffering from high expectations from teachers and parents. How's that for laughter getting out of hand? So the next time you laugh in a social situation, think about why you're laughing. Did you really think that joke was funny or were you just trying to please who you were with? Have you ever laughed at a joke for a long time only to realize it wasn't actually that funny? Comment below. We'd love to hear your laughing stories.