Like fear, disgust is required for
survival. A species can cling to precious
life based on their ability to find that piece of
brown,
rotting, smelling meat too wretched to
eat.
There is actually a 25 year old man who had a stroke that destroyed the area of his brain where he once experienced disgust. While he recognized all other facial expressions(happy, fearful, angry, sad, and surprised) he was unable to detect disgust. This was not only for faces, he also did not recognize retching sounds or numbers recited in a disgusted manner.
Even disgusting ideas, such as friends who only change their underwear once a week did not insight a response in this man.
This study shows that the area of the brain used to interpret an emotion is the same as the emotion itself. It is an insight into how emotions tend to spread throughout a group.
It is interesting to think about the range of occupations such a man could bear without this section of his brain... Crime scene cleaner? Solid waste engineer? Prison guard? Call girl? Social worker? The opportunities are endless in the seemingly large disgusing segment of the world.