Female funny bone begins in brain

When a particular joke goes over well with one sex and not the other, you might chalk it up to biology. Apparently, there are differences in humor appreciation between the sexes.

Using functional MRI, Stanford University researchers found that women and men had similar neurological responses to a series of black-and-white cartoons. Women, however, tended to make greater use of the nucleus accumbens, implying greater reward network response (Proc Natl Acad Sci USA 2005;102[45]:16496-16501).

The nucleus accumbens is associated with psychological reward, including situations of self-reported happiness, monetary reward, the processing of attractive faces, and cocaine-induced euphoria.

Researchers said that insight into these sex differences may aid in understanding the pathogenesis of neuropsychiatric disorders, most notably depression, an affliction that strikes twice as many women as men, with dramatic effects on the capacity to experience reward.