New research suggests that the highest functions of our brains handle the lowest form of wit.
The research has found that the ability to understand sarcasm depends on a carefully orchestrated sequence of complex cognitive skills in specific parts of the brain.
Dr Shamay-Tsoory, a psychologist at the Rambam Medical Centre in Haifa and the University of Haifa, says that sarcasm is related to our ability to understand other people's mental state and is not just a linguistic form, it is related to social cognition.
The research revealed that areas of the brain that decipher sarcasm and irony also process language, recognise emotions and help us understand social cues.
Simone Shamay-Tsoory and colleagues say that understanding other people's state of mind and emotions is related to our ability to understand sarcasm.
The team recruited 41 people who had suffered mild brain damage following accidents or illness together with 17 healthy volunteers, and the scientists looked at how they understood neutral and sarcastic statements read by actors.
One sarcastic example was, "Joe came to work and instead of beginning to work he sat down to rest. His boss noticed his behaviour and said 'Joe don't work too hard'."
In the neutral version, Joe begins to work as soon as he arrives and his boss's reaction is the same.
The study showed that people with damage in the prefrontal lobe struggled to pick out sarcasm. The others, including people with similar damage to other parts of the brain, were able to correctly place the sharp-tongued words into context.
The prefrontal lobe is known to be involved in pragmatic language processes and complex social cognition. The ventromedial section is linked to personality and social behaviour.
Dr Shamay-Tsoory said the loss of the volunteers' ability to understand irony was a subtle consequence of their brain damage, which produced behaviour similar to that seen in people with autism.