Appreciation of humor doesn't change with age

A Canadian study of humor in older adults has found that appreciation and emotional reactiveness to humor doesn't change with age. Older adults still enjoy a good laugh.

However, the ability to comprehend more complex forms of humor diminishes in later years.

The findings are published in the September issue of the Journal of the International Neuropsychological Society. Lead researcher Dr. Prathiba Shammi, a psychologist with Baycrest Centre for Geriatric Care, conducted the study with the supervision of Dr. Donald Stuss, psychologist and Director of The Rotman Research Institute at Baycrest. The research was part of Dr. Shammi's doctoral thesis at the University of Toronto.

Shammi and Stuss captured world attention in 1999 for their landmark study (published in the journal BRAIN) showing the 'right' frontal lobe plays a pre-eminent role in our ability to appreciate humor. They found that subjects with right frontal damage -- from stroke, tumor or head trauma -- not only had difficulty getting punch lines, but preferred slapstick humor.

In this current study, a second phase of the earlier study, Shammi and Stuss explored the effects of normal aging on humor comprehension and appreciation.

Humor 'comprehension' is defined as the ability to cognitively or intellectually understand humorous material, which may be assessed by the ability of the responder to select appropriate punch lines to jokes or provide appropriate logical reasoning as to why a stimulus is humorous. Humor 'appreciation' is the affective or emotional response to humorous stimuli (such as smiling, laughing) once the humor has been cognitively processed and understood at some level.

"The good news is that aging does not affect emotional responses to humor -- we'll still enjoy a good laugh when we get the joke," says Dr. Shammi. "This preserved affective responsiveness is important because it is integral to social interaction and it has long been postulated that humor may enhance quality of life, assist in stress management, and help us cope with the stresses of aging."

However, results from the study also suggest that the ability to comprehend more complex forms of humor may diminish in our later years. Why? The cognitive abilities required for humor comprehension include abstract reasoning, mental flexibility and working memory -- all are complex, higher mental functions believed to be associated with the frontal lobes. Biological evidence suggests that the brain's frontal functions may be the first to deteriorate with aging. While scientists continue to debate this evidence, it may explain why older adults can have difficulty understanding more complex forms of humor.

Participants in the study included 20 healthy older adults (average age 73)and 17 healthy younger adults (average age 28), all right-handed and conversationally fluent in English. They were asked to complete three separate humor tests: appreciation of humorous verbal statements; joke and story completion; and nonverbal cartoon appreciation.

In the first test, participants were presented with 21 humorous and seven neutral written statements and asked to pick out the humorous ones. Examples of humor statements included: (i) Sign in a tailor shop -- "Please have a fit upstairs"; and (ii) Sign in a hotel -- "Guests are invited to take advantage of the chambermaid". An example of a neutral statement included: (i) Sign in a hotel -- "Visitors are requested to turn off the lights when they leave the room".

In the second test, participants were asked to select the correct punch lines for 16 incomplete joke stems. Each joke stem had four different endings of which only one was the correct (humorous) punch line. The four different endings included the funny correct ending (FC), the logical straightforward ending (SF), the slapstick humorous non sequitur ending (HNS), and the unrelated non sequitur (UNS). For example: The neighbor approached Mr. Smith at noon on Sunday and inquired, 'Say Smith, are you using your lawnmower this afternoon?' 'Yes I am,' Smith replied warily. Then the neighbor answered -- 'Fine, you won't be wanting your golf clubs, I'll just borrow them' (FC); 'Oops!' as the rake he walked on barely missed his face (HNS); 'Oh well, can I borrow it when you're done, then?' (SF); and 'The birds are always eating my grass seed' (UNS).

In the third test, participants looked at 10 different cartoon drawings. Each cartoon consisted of a series of four similar drawings, only one of which had a funny detail. Participants were asked to select the correct funny version.

Researchers found that the older adults performed just as well as their younger counterparts in the first simple test: differentiating humorous from neutral verbal statements. However, older adults made significantly greater errors in the other two more cognitively challenging tests: selecting the correct punch lines to joke stems AND selecting the correct funny cartoon from an array of cartoons.

A series of neuropsychological tests were also administered to assess cognitive abilities in abstract reasoning, mental flexibility and working memory. Researchers compared these tests to performance on the humor tests for the older group only and found a "significant co-relation" between the decline in these cognitive abilities and a higher error rate on selecting correct punch lines and funny cartoons.

Despite these deficits in humor 'comprehension', older adults did not differ from the young in terms of their affective responses (i.e. appreciation of humor). They reacted appropriately with a smile or laugh when they understood the humor. This suggests that, while cognitive abilities thought to be mediated by dorsolateral frontal regions related to humor may deteriorate with aging, affective processing related to orbital and medial prefrontal regions may remain intact.

The authors caution against over-interpreting the results of this preliminary study. Although the results suggest a difficulty with processing complex humorous material with age, many factors such as cohort differences in the type of humor preferred, social setting, and health all contribute to our response to humorous situations.

The study was funded by the Canadian Institutes of Health Research. Baycrest Centre for Geriatric Care is an academic health sciences centre affiliated with the University of Toronto.