Memory and learning are more difficult in advanced age, and improving these skills improves quality of life for older adults. Mounting research, like this new study, shows that humor might be appropriately viewed as a complementary therapy to overcome these age-related cognitive abilities. Formal laughter therapy programs and even laughter yoga – a group practice involving voluntary laughter – have emerged in recent years as prescribed therapies for patients with cancer, diabetes, high blood pressure, high cholesterol, depression, anxiety, and many other conditions. Interestingly, the benefits of laughter appear to be the same whether the laughter is spontaneous or self-induced and whether it occurs with or without humor.

That last sentence IS interesting. Makes me wonder what the essence of laughter is.