Hahahaha
For the 2002 rock album, see Laugh (Keller Williams album).
Two girls laughing
Late 19th century or early 20th century depiction of different stages of laughter on advertising cards
Laughter is an audible expression, or appearance of merriment or happiness, or an inward feeling of joy and pleasure (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 a part of human behaviour regulated by the brain.
It helps humans clarify their intentions in social interaction and provides 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. An extreme case of this is the Tanganyika laughter epidemic. This may account in part for the popularity of laugh tracks in situation comedy television shows.
The study of humor and laughter, and its psychological and physiological effects on the human body is called gelotology.
Laughter in animals
Laughter is not confined or unique to humans, despite Aristotle's observation that "only the human animal laughs".
However, some behavioral psychologists argue that self-awareness of one's situation, or the ability to identify with another's predicament are prerequisites for laughter, and thus certain animals are not laughing in the "human manner".
Laughter is a rich experience and expression in human beings. Owners of pets can vouch on this point, if they understand when their pet is happy and how it expresses the same.
According to Dr.
Shriniwas Kashalikar, self awareness is conscious concommitant of the physiological processes involving laughter or smiling reflex and its grades, degrees or spectrum varies according to phylogenetic development, with no clear cut demarcation. The emotional ingredients are variable and involve different neurophysiological and physiological processes.
Self awareness and ability to identify with another's predicament may be prerequisite to intellectual jokes with specific references and contexts, but not for laughing behavior as such.
Laughing also feels good.
An Orangutan "laughing"
Research of laughter in animals may identify new molecules to alleviate depression, disorders of excessive exuberance such as mania and ADHD, or addictive urges and mood imbalances.
Non-human primates
Chimpanzees, gorillas, bonobos and orangutans show laughter-like vocalizations in response to physical contact, such as wrestling, play chasing, or tickling. Chimpanzee laughter is not readily recognizable to humans as such, because it is generated by alternating inhalations and exhalations that sound more like breathing and panting.
The differences between chimpanzee and human laughter may be the result of adaptations that have evolved to enable human speech. It is hard to tell, though, whether or not the chimpanzee is expressing joy.
One study analyzed and recorded sounds made by human babies and bonobos (also known as pygmy chimpanzees) when tickled. It found that although the bonobo’s laugh was a higher frequency, the laugh followed the same spectrographic pattern of human babies to include as similar facial expressions.
Humans and chimpanzees share similar ticklish areas of the body such as the armpits and belly. These are certain areas of the body that generate more laughter response than others.
The laughter is associated with positive emotional feelings and social bonding occurs with the human tickler, resulting in the rats becoming conditioned to seek the tickling. Additional responses to the tickling were those that laughed the most also played the most, and those that laughed the most preferred to spend more time with other laughing rats.
The initial goal of Jaak Panksepp and Jeff Burgdorf’s research was to track the biological origins of joyful and social processes of the brain by comparing rats and their relationship to the joy and laughter commonly experienced by children in social play. Panksepp & Burgdorf 2003 Chirping by rats is also reported in additional studies by Brain Knutson of the National Institutes of Health.
Rats chirp when wrestling one another, before receiving morphine, or when mating. Science News 2001
Dogs
The dog laugh sounds similar to a normal pant.
When this recorded dog-laugh vocalization is played to dogs in a shelter setting, it can initiate play, promote pro-social behavior, and decrease stress levels. Dogs ranging from 4 months to 10 years of age were compared with and without exposure to a dog-laugh recording.
The stress behaviors measured included panting, growling, salivating, pacing, barking, cowering, lunging, play-bows, sitting, orienting and lying down. The study resulted in positive findings when exposed to the dog laughing: significantly reduced stress behaviors, increased tail wagging and the display of a play-face when playing was initiated, and the increase of pro-social behavior such as approaching and lip licking were more frequent.
There are thousands of languages, hundreds of thousands of dialects, but everyone speaks laughter in pretty much the same way.” Everyone can laugh. Children who are born blind and deaf still retain the ability to laugh.
“Even apes have a form of ‘pant-pant-pant’ laughter.”
Provine argues that “Laughter is primitive, an unconscious vocalization.” And if it seems you laugh more than others, Provine argues that it probably is genetic. Provine reports that “until they met each other, neither of these exceptionally happy ladies had known anyone who laughed as much as she did.” They reported this even though they both had been brought together by their adoptive parents they indicated were “undemonstrative and dour.” Provine indicates that the twins “inherited some aspects of their laugh sound and pattern, readiness to laugh, and perhaps even taste in humor.” WebMD 2002
Raju Mandhyan states "The physical and psychological benefits of laughter come second only to the physical and psychological benefits of sex."
Gender differences
Men and women take jokes differently.
A study that appeared in Proceedings of the National Academy of Sciences found in a study, 10 men and 10 women all watched 10 cartoons, rating them funny or not funny and if funny, how funny on a scale of 1–10. Women’s brains showed more activity in certain areas, including the nucleus accumbens.
When women viewed cartoons they did not find humorous, their nucleus accumbens had a “ho-hum response.” A man's nucleus accumbens did not react to funny cartoons, and its natural activity level dropped during unfunny cartoons.
Researchers suspect the element of surprise may be at the heart of the study. They suggested that maybe women did not expect the cartoons to be funny, while men did the opposite.
When the men in the study “got what they expected, their nucleus accumbens were calm.” However, the women’s brains could have had increased activity when they were “pleasantly surprised” by the cartoons’ humour. Researchers also suspect that men might have been “let down by unfunny cartoons, causing a dip in that brain area’s activity.”
It was indicated that this study might be a clue about the different emotional responses between men and women and could help with depression research.
So while purely emotional responses such as laughter are mediated by subcortical structures, especially the hypothalamus, and are stereotyped, the cerebral cortex can modulate or suppress them."
Causes
Common causes for laughter are sensations of joy and humor, however other situations may cause laughter as well.
A general theory that explains laughter is called the relief theory. This theory is one of the justifications of the beliefs that laughter is beneficial for one's health. This theory explains why laughter can be as a coping mechanism for when one is upset, angry or sad.
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.
For example, this is how this theory works in the case of humour: a joke creates an inconsistency, the sentence appears to be not relevant, and we automatically try to understand what the sentence says, supposes, doesn't say, and implies; if we are successful in solving this 'cognitive riddle', and we find out what is hidden within the sentence, and what is the underlying thought, and we bring foreground what was in the background, and we realize that the surprise wasn't dangerous, we eventually laugh with relief.
Otherwise, if the inconsistency is not resolved, there is no laugh, as Mack Sennett pointed out: "when the audience is confused, it doesn't laugh" (this is the one of the basic laws of a comedian, called "exactness"). It is important to note that the inconsistency may be resolved, and there may still be no laugh.
Due to the fact that laughter is a social mechanism, we may not feel like we are in danger, however, the physical act of laughing may not take place.