Scientists have uncovered hard evidence of a gender divide when it comes to appreciating humour.
Is the male sense of humour less analytical?
A Stanford University team monitored brain activity when men and women looked at funny cartoons.
They found areas of the brain involved in language processing, memory and generating reward feelings were more likely to be activated in women.
It is hoped the Proceedings of the National Academy of Sciences study may provide insights into depression.
It may also lead to a better understanding of other medical conditions, such as cataplexy - a sudden loss of control of movement linked to the emotions.
Men and women showed no significant difference in the number of cartoons they rated as funny
Women were quicker at identifying material they considered unfunny
Lead researcher Professor Allan Reiss said: "The results help explain previous findings suggesting women and men differ in how humour is used and appreciated."
The prefrontal cortex, which is involved in language processing and memory, is known to play a role in humour appreciation.
And the Stanford team has shown that the mesolimbic reward centre - responsible for generating the positive feelings associated with events such as monetary gain - is also activated by humour.
The latest study used sophisticated scans to monitor the brains of 10 men and 10 women as they watched 70 black-and-white cartoons.
The researchers found similarities between the way that male and female brains respond to humour.
But some brain regions were activated more in women, including both the left prefrontal cortex and the mesolimbic reward centre.
The researchers say their findings suggest women place a greater emphasis on the language of humour, possibly employing a more analytical approach.
They also believe that the women in the study were less likely to expect the cartoons to be funny - so when they were, their pleasure centre lit up with greater intensity than their male counterparts.
Professor Reiss said: "Women appeared to have less expectation of a reward, which in this case was the punch line of the cartoon.
"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 centre was activated in women.
That was not the case in men who seemed to "expect" the cartoons to be funny from the start.
Professor Reiss said the finding that women's reward centres might be more sensitive to emotional stimuli, if confirmed by follow-up studies, might explain why they appear to be more vulnerable to depression.
Professor Tonmoy Sharma, of the Clinical Neuroscience Research Centre in Dartford, Kent, said it was certainly the case that women were more likely to become depressed.
However, he told the BBC News website: "I would agree that women are much more analytical in terms of humour, but to extrapolate from this study, and draw conclusions about clinical depression is probably a step too far."