Laughter may not only be the best medicine; it may also offer a way to improve memory, according to a study presented at the 2014 Experimental Biology Meeting, held in April 2014 in San Diego.
Researchers from Loma Linda University in Loma Linda, California, presented the study, which examined the relationship between cortisol and memory, and investigated whether humor and laughter could reduce the damage that cortisol can cause to the brain. Cortisol, a stress hormone, is known to affect memory and learning ability in older adults.
Researchers showed a funny 20-minute video to two groups of elderly adults—one comprising healthy individuals and the other consisting of people with diabetes--and then asked participants to complete a test that evaluated learning, recall and sight recognition. Cortisol levels were measured before and after the video performance. Test results were compared against those of a control group that had not watched the funny video.
Data analysis showed that both groups that had watched the funny video had lower cortisol levels than the control group. The people with diabetes experienced the most change in cortisol totals, while the healthy older adults showed the most improvement in memory test scores. All funny-video viewers scored higher than control group members on every aspect of memory.
Lee Berk, DrPH, a study co-author, said in a press release from the Federation of American Societies for Experimental Biology, “It’s simple. The less stress you have, the better your memory. Humor reduces detrimental stress hormones like cortisol that decrease memory hippocampal neurons, lowers your blood pressure, and increases blood flow and your mood state. The act of laughter—or simply enjoying some humor—increases the release of endorphins and dopamine in the brain, which provides a sense of pleasure and reward. These positive and beneficial neurochemical changes, in turn, make the immune system function better. There are even changes in brain wave activity towards what’s called the ‘gamma wave band frequency,’ which also amp up memory and recall.”