Men expect something to be funny.
Women don't, and are therefore surprised.
http://www.eurekalert.org/pub_releases/2005-11/sumc-gda110205.php wrote:STANFORD, Calif. - Need more evidence that men and women are different? Look no further than the Sunday funnies. According to a new Stanford University School of Medicine study, gender affects the way a person's brain responds to humor.
The first-of-its-kind imaging study showed that women activate the parts of the brain involved in language processing and working memory more than men when viewing funny cartoons. Women were also more likely to activate with greater intensity the part of the brain that generates rewarding feelings in response to new experiences.
"The results help explain previous findings suggesting women and men differ in how humor is used and appreciated," said Allan Reiss, MD
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Reiss said he was taken off guard by the NAcc finding. After puzzling over it, he and his colleagues theorized that because the women in this study used more analytical machinery when deciphering humorous material, it signaled that they weren't necessarily expecting the cartoons to be as rewarding as did the men. When a woman's brain encountered the punch line, her reward center lit up. According to Reiss, the activation of this center not only signals the presence of something pleasant, but that the pleasure was unexpected.
"Women appeared to have less expectation of a reward, which in this case was the punch line of the cartoon," said Reiss. "So when they got to the joke's punch line, they were more pleased about it."
The researchers also found that the funnier the cartoon, the more the reward center was activated in women. That was not the case in men who seemed to "expect" the cartoons to be funny from the start.
