(NEW YORK) -- Ever have trouble remembering where you just left your keys? Just laugh it off. New research suggests that humor can improve short-term memory in older adults. In a recent small study conducted at Loma Linda University in Southern California, 20 normal, healthy, older adults watched a funny video distraction-free for 20 minutes, while a control group sat calmly with no video.
Afterwards, they performed memory tests and had saliva samples analyzed for stress hormones. Those who got to laugh the 20 minutes away with the funny video scored better on short-term memory tests, researchers said. And salivary levels of the stress hormone cortisol -- a memory enemy of sorts -- were significantly decreased in the humor group.
"Learning ability and delayed recall become more challenging as we age," said study author Dr. Gurinder S. Bains, a Ph.D. candidate in Rehabilitation Sciences. "Laughing with friends or even watching 20 minutes of humor on TV, as I do daily, helps me cope with my daily stressors."
The less stress you have, researchers said, the better your memory. It works like this: humor reduces stress hormones, lowers your blood pressure, and increases your mood state, according to Dr. Lee Berk, a co-author of the study and associate professor of Allied Heath.
The act of laughter-- or simply enjoying some humor-- increases endorphins, sending dopamine to the brain to provide a sense of pleasure and reward, Berk said.
That, in turn, makes the immune system work better and changes brain wave activity towards what's called a "gamma frequency," amping up memory and recall.
Want to lower your stress levels?
"Begin by laughing more daily," Bains said. "It will improve your quality of life."
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