By Jennifer Viegas
                                                      Special to ABCNEWS.com 2000

                       A new study suggests sense of humor is a learned trait, influenced by family
                   and cultural environment.
                        The study, published in this week’s New Scientist, laughs off the theory
                   that humans possess a joke gene, because genetic factors don’t seem to have
                   any impact on humor appreciation.

                   Cartoon Connoisseurs
                   Researchers came to this conclusion after studying 127 pairs of female twins
                   at the Twin Research Unit, St. Thomas Hospital, London. Seventy-one of the
                   twin pairs were identical, meaning that they possess the same genes, while the
                   rest of the test subjects were fraternal twins who, on average, share about 50
                   percent of their genes — no more than do ordinary siblings.
                        In what had to be one of the most fun scientific studies ever, the twins
                   were asked to go into separate rooms and rate five Gary Larson The Far
                   Side cartoons from zero to 10. Zero meant the cartoon was a boring dud, 5
                   indicated the joke was fair, and 10 meant it was one of the funniest things
                   they’d ever seen.
                        Fans of The Far Side might recall the cartoons that were used in the test.
                   Tim Spector, director of the Twin Research Unit, and lead author of the
                   study, describes three of them:
                              1. A dog tethered to the mast of a Viking ship wags its tail as its
                   owner and other Vikings return from a burning and presumably pillaged
                   castle.
                              2. A group of people stands in a doorway to a room in which a
                   composer sits at his piano. The composer’s head is slumped against the
                   keyboard and his arm, or the skeletal remains thereof, hangs to his side. The
                   caption below reads “shhhh! the Maestro is decomposing!”
                              3. A woman stands in her living room, peering into a fishbowl; her
                   eye magnified and distorted by the water. Meanwhile, an enormous eye fills
                   the window of the room she’s in, staring at her.

                   No Difference
                   Surprisingly, the identical twins shared no more common responses to the
                   jokes than did the fraternal twins during the study. In fact, the fraternal twins
                   often were in closer agreement as to which jokes seemed funny, and which
                   cartoons appeared to be a waste of paper.
                        “We found that between one-third and two-thirds of the variability in
                   reaction to the cartoons was due to shared environmental effects such as
                   family upbringing,” says Spector. “Genetic factors did not appear to
                   contribute at all.”
                        He adds that teachers, classmates, “dad’s jokes,” culture and religion all
                   help to shape sense of humor.

                   Why The Far Side?
                   One of the reasons Larson’s cartoons were chosen for the study is that they
                   contain cognitive, or “off the wall,” humor. Spector explains, “Cognitive is the
                   good sensation that comes over you when you get the joke.” Such a sensation
                   comes from the sudden mental integration of incongruous ideas, attitudes or
                   situations.
                        Spector chose to use this kind of humor for the study because responses
                   to it are variable. He says some people love The Far Side, for example,
                   while others just don’t get it at all. Also, cognitive jokes make good test
                   material because they’re generally not offensive.
                        The three other defined humor types are not quite as sophisticated.
                   “Conative” humor produces a smug feeling of superiority from other people’s
                   misfortune, such as when we laugh at someone tripping on a banana peel.
                   “Affective” humor involves racial or smutty jokes. “Orectic” humor combines
                   the previously two mentioned types.

                   Men Are Another Story
                   The participants in this study were all females, but what about males? Spector
                   says other research indicates that both men and extroverted women tend to
                   appreciate orectic jokes. It’s not clear why, though.
                        Further, the mirth-meter for men and extroverts seems to depend upon, as
                   Spector puts it, “the cognitive demand of the stimulus and the individual’s
                   psychometric abilities.” That’s a scientific way of saying it helps to be smart
                   when presented with a more subtle, sophisticated cartoon or joke.
                        There is also evidence that humor appreciation varies with age and
                   personality. For instance, a more staid person is likely not to guffaw at a
                   liberal, racy joke.
                        Robert Plomin, a behavioral geneticist at the Institute of Psychiatry in
                   London, says Spector’s research “is interesting, because twin studies of
                   personality traits almost always show genetic effects.” However, he thinks a
                   larger research project is needed to confirm the findings.
                        Spector and his team next hope to test the other types of humor, including
                   sexual innuendo.

                    Brain Damaged People Prefer Slapstick Humor

                    Last year, scientists identified the part of the brain responsible for humor
                    appreciation. As it turns out, the right anterior frontal lobe is our
                    chuckle-producing chunk of gray matter, according to researchers at the
                    Rotman Research Institute of the University of Toronto. When this part of
                    the brain is damaged — such as by stroke, tumor or surgical removal —
                    humor appreciation is impaired.
                         The researchers came to this conclusion after asking study participants to
                    choose the appropriate punch line for a written joke. For example:
                         The neighborhood borrower approached Mr. Smith Sunday noon and
                    inquired, “Say Smith, are you using your lawnmower this afternoon?” “Yes,
                    I am,” Smith replied warily.
                         Then the neighborhood borrower answered:
                            A. “OOPS!” as the rake he walked on barely missed his face.
                    (slapstick)
                            B. “Fine, then you won’t be wanting your golf clubs, I’ll just borrow
                    them.” (correct, because it requires the reader to look for a higher level of
                    meaning amongst the other possible responses)
                            C. “Oh well, can I borrow it when you’re done, then?”
                    (straightforward logical choice) or
                            D. “The birds are always eating my grass seed.” (illogical)
                         Test results indicated that people with damage to the humor appreciation
                    part of their brain tended to choose the slapstick ending.