neurophysiologist katherine rankin at the university of california, SF, has recently discovered that sarcasm plays an important part in human social interaction. like we didn't already know that. according to the good doctor, those who can't readily discern sarcasm appear to have less functional/evolved parahippocampal gyrus regions in their right brain. that cortex of the brain not only controls certain memory recall functions and visual recollections, but registers social contexts. she notes that people with dementia, or head injuries in that area, often lose the ability to pick up on sarcasm, and so they don’t respond in a socially appropriate ways. (which makes me wonder if damn near ALL of my relatives weren't dropped on their heads as children).
we use sarcasm to form alliances with people with whom we are socially compatible and to pick out "enemies" who, to simplify, may represent a threat to our personal advancement. it is this mastery of "social intelligence" (which encompasses humor, conversational ability, friend/foe recognition, and sarcasm), anthropologists say, that has allowed the human race to thrive and evolve. (and i thought it was TV that brought us this far)