Humour is a universal human characteristic; it may even define us (Image: Bill Truslow/Stone/Getty) All jokes rely on some kind of incongruity that can be resolved to a greater or lesser degree – a process that is reflected in a region of the brain known as the temporoparietal junction. This cartoon is an example of a straighter, more resolvable joke, where the incongruity (the replacement of Pavlov’s dog with a salivating Pavlov) is very easily explained (Image: www.CartoonStock.com) In some jokes, however, the incongruities are harder to resolve. These cartoons appeal more to a psychological group known as “experience seekers”, who are defined by their desire to pursue novel sensations. These people show greater activity in their temporoparietal junction, hippocampus and prefrontal cortex as they explore all the possible angles of the joke (Image: www.CartoonStock.com) Many cartoons, dubbed theory-of-mind jokes, rely on the viewer understanding a situation from two different peoples’ points of view (in this case, the cat and the scientist’s mindsets). These jokes are particularly difficult for people with autism to understand (Image: www.CartoonStock.com) Autistic people prefer visual puns, which do not rely on an understanding of the character’s mindset, to the theory-of-mind jokes. Here, the joke relies on the viewer understanding the fact that one visual element (in this case, the crab’s claw/spanner) represents two things simultaneously (Image: www.CartoonStock.com)

TWO polar bears are perched on a block of floating ice. One says to the other: “Do you know, I keep thinking it’s Thursday…”

To some, this kind of surreal humour is side-splitting. Others are baffled by it and can’t even raise a smile. …