Dancing At Garden Grove October 17th 2009

Did you know? - Laughter is an audible expression or appearance of happiness, or an inward feeling of joy (laughing on the inside). It may ensue (as a physiological reaction) from jokes, tickling, and other stimuli. Inhaling nitrous oxide can also induce laughter; other drugs, such as cannabis, can also induce episodes of strong laughter. Strong laughter can sometimes bring an onset of tears or even moderate muscular pain.

Laughter is found among various animals, as well as in humans. Among the human species, it is a part of human behavior regulated by the brain, helping humans clarify their intentions in social interaction and providing an emotional context to conversations. Laughter is used as a signal for being part of a group — it signals acceptance and positive interactions with others. Laughter is sometimes seemingly contagious, and the laughter of one person can itself provoke laughter from others as a positive feedback. This may account in part for the popularity of laugh tracks in situation comedy television shows.

Scientifically speaking, laughter is caused by the epiglottis constricting the larynx, causing respiratory upset. The study of humor and laughter, and its psychological and physiological effects on the human body is called gelotology.