An attack of the giggles can sometimes appear at the strangest moments . Whether it 's during a speech or in a meeting , helpless laughter is one of our most insightful behaviours , according to neuroscientist Sophie Scott . In a recent Ted Talk in Vancouver , Professor Scott revealed that laughter often is n't to do with comedy value , but with our relationships with others . Laughter is often used as a tool for social bonding rather than in reaction to something that has comedy value , according to UCL Professor Sophie Scott . Pictured are Prime Minister David Cameron and US President Barack Obama during a basketball game . According to David Robson at BBC Future , Scott 's study of people in Nambia revealed that laughter is a key cultural mechanism that helps social bonding . When Scott asked indigenous Namibians and English people to listen to recordings of each other and describe the emotions , laughter was the most recognisable . 'People genuinely think they are mostly laughing at other people 's jokes , but within a conversation , the person who laughs most at any one time is the person who is talking , ' she told the BBC . The University College London professor 's current research aims to distinguish the difference between fake laughs used during conversation , and involuntary giggles . She has carried out brain scans on volunteers listening to expressions of disgust , a real belly laugh and a realistic fake one . Laughter activates the brain 's mirror regions that mimic other 's actions , and she says this is the reason behind why laughing can be so contagious . So far , her research has found that volunteers were almost always able to identify a false laugh . She has also discovered that less authentic tones are more nasal , and belly laughs never come through the nose . Researchers from Indiana State University found that with laughter can boost the immune system by up to 40 per cent . The study tested 33 healthy women . Half of the women watched a comedy video together while the others watched a dull video on tourism . When the films were over , scientists took samples of the women 's immune cells , known as natural killer cells , and mixed them with cancer cells to see how effectively they attacked the disease . They found that the women who had found the comedy funny enough to laugh out loud had significantly healthier immune systems afterwards than those who had watched the tourism film . Meanwhile , MRI scans revealed how hearing real and fake laughter activates two different areas of our brains . Fake laughter triggers more brain activity – in the medial prefrontal cortex , associated with problem-solving – as we try to work out why the person is doing it . Genuine laughter simply activates auditory areas in the temporal lobe – where we process all sound . But both activate the brain 's mirror regions that mimic other 's actions , and she says this is the reason behind why laughing can be so contagious . 'You are 30 times more likely to laugh if you 're with someone else , ' she claims . To further her work , Scott has recently set up an experiment at London 's Science Museum , where she will be asking visitors to judge the authenticity of different clips of people laughing . And she believes far more research needs to be done on this cultural tic . 'If you search on the Web of Science database for papers on the emotion of fear , you 'll get back 6,477 published papers , ' Professor Scott writes on Ted . 'Search for papers on laughter and you 'll get a paltry 175 . Why the disparity ? Well , one reason might be that laughter , like other positive emotions , feels less important than negative emotions . 'Sometimes people think that laughter is a ridiculous , trite , pointless topic to research…I think it 's a fascinating social behaviour , it is essential to study . ' In a separate study last year , psychologist Dr Carolyn McGettigan from the Royal Holloway University of London measured brain responses of volunteers as they listened to genuine laughter on YouTube clips . Each participant was asked to pick clips they found funny . This ranged from comedy shows , such as Flight Of The Conchords , and even the Eurovision Song Contest . The results were then compared to how their brains responded to fake laughter . The findings revealed participants , none of which were told the study was about laughter perception , could unconsciously tell when the chuckles were insincere . Dr McGettigan said : 'It 's fascinating to consider the way our brain is able to detect genuine happiness in other people . 'Our brains are very sensitive to the social and emotional significance of laughter .
Professor Sophie Scott says laughter often is n't to do with comedy value . In a conversation , the person who laughs most is usually the one talking . People are up to times more likely to laugh if they are with someone else . It also triggers brain 's mirror region which explains why it is contagious .