Hi Laura,
I'm interested in exploring this topic, too, because I know people who laugh at odd moments... or maybe not laugh, but let off a few... well, almost snide "chuckles"... about the strangest things, like when mentioning a news story about someone who's just passed away.
Here's a bit from Wikipedia, just for starters:
http://en.wikipedia.org/wiki/LaughterAbnormal laughter
Researchers frequently learn how the brain functions by studying what happens when something goes wrong. People with certain types of brain damage produce abnormal laughter. This is found most often in people with pseudobulbar palsy, gelastic epilepsy and, to a lesser degree, with multiple sclerosis, amyotrophic lateral sclerosis (ALS) , and some brain tumors. Inappropriate laughter is considered symptomatic of psychological disorders including dementia and hysteria. Some negative medical effects of laughter have been reported as well, including laughter syncope, where laughter causes a person to lose consciousness.[3]
[edit] Why we laugh
A number of competing theories have been written. For Aristotle, we laugh at inferior or ugly individuals, because we feel a joy at being superior to them. Socrates was reported by Plato as saying that the ridiculous was characterized by a display of self-ignorance. Francis Hutcheson expressed in Thoughts on Laughter (1725) what became a key concept in the evolving theory of the comic: laughter as a response to the perception of incongruity.[4] Schopenhauer wrote that the perceived incongruity is between a concept and the real object it represents. Hegel shared almost exactly the same view, but saw the concept as an "appearance" and believed that laughter then totally negates that appearance. For Freud, laughter is an "economical phenomenon" whose function is to release "psychic energy" that had been wrongly mobilized by incorrect or false expectations.
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Philosopher John Morreall theorizes that human laughter may have its biological origins as a kind of shared expression of relief at the passing of danger. The General Theory of Verbal Humor (GTVH) proposed by Victor Raskin and S. Attardo identifies a semantic model capable of expressing incongruities between semantic scripts in verbal humor; this has been seen as an important recent development in the theory of laughter. Recently Peter Marteinson theorized that laughter is our response to the perception that social being is not real in the same sense that factual states of affairs are true, and that we subconsciously blur the distinctions between cultural and natural truth types, so that we do not normally notice their differing criteria for truth and falsehood. This is an ontic-epistemic theory of the comic (OETC).
Robert A. Heinlein's view of why people laugh is explained in one of his most praised novels, Stranger in a Strange Land, "because it hurts", is empathic but also a release of tension.
Laughter can also be used as a coping mechanism for when one is upset, angry or sad. It does not necessarily always occur in a humorous or comedic tone. However, the 'comedic tone' is not an existing reality; rather, the reality becomes 'comedic' only when laughter ensues. This concept is intended to debunk the false categorization of 'funniness' to a situation.
I'm looking forward to hearing others' stories/opinions about this and will keep reading. Thanks for the topic, Laura.
Hope