Jimmy Carr and the science of laughter.

This Horizon Special explores the science of laughter. Jimmy Carr is joined by Professor Sophie Scott who explains that there are a set of basic human emotions that are shared across all cultures although what makes us laugh varies a lot. She also talks about the physiological process of laughing. Professor Robin Dunbar also participates in the programme; he studies pain and, in particular, the way that laughter can alter pain thresholds. The different types of laughter are analysed including real laughter and posed laughter. Peter McGraw discusses the three main theories of comedy - superiority theory, release / relief theory and incongruity theory. Professor Jaak Pansek describes his research into proving that rats laugh. The conclusion is that laughter is a social emotion which makes you healthier whilst comedy helps us to see what's wrong with the world.