The purity in Kids smile, the romance in your crush smile, the nudity of a nasty fellow's smile, the fake smile when you see you boss and there are more.
A smile seems to have a favorable influence upon others and makes one likable and more approachable. In the social context, smiling and laughter have different functions in the order of sequence in social situations:
Smiling is not a pre-laughing device and is a common pattern for paving the way to laughter;
Smiling can be used as a response to laughter in the previous turn.
Smiling is a signaling system that evolved from a need to communicate information of many different forms. One of these is advertisement of sexual interest. Female smiles are appealing to heterosexual males, increasing physical attractiveness and enhancing sex appeal. However, recent research indicates a man's smile may or may not be most effective in attracting heterosexual women, and that facial expressions such as pride or even shame might be more effective. The researchers ignored the role of smiles in other sexual preferences.
There are 18 different smiles including polite, cruel, false, self-effacing and so on., but you know only one smile, the Duchenne smile, reflects genuine happiness. It has been named in honor of the French neurologist who determined this phenomenon, Guillaume-Benjamin-Amand Duchenne (de Boulogne).
Duchenne smile
A Duchenne smile engages the muscles around the mouth and eyes.
While conducting research on the physiology of facial expressions in the mid-19th century, French neurologist Guillaume Duchenne identified two distinct types of smiles. A Duchenne smile involves contraction of both the zygomatic major muscle (which raises the corners of the mouth) and the orbicularis oculi muscle (which raises the cheeks and forms crow's feet around the eyes).
A non-Duchenne smile involves only the zygomatic major muscle. "Research with adults initially indicated that joy was indexed by generic smiling, any smiling involving the raising of the lip corners by the zygomatic major. More recent research suggests that smiling in which the muscle around the eye contracts, raising the cheeks high (Duchenne smiling), is uniquely associated with positive emotion.".
The Pan Am smile, also known as the "Botox smile", is the name given to a fake smile, in which only the zygomatic major muscle is voluntarily contracted to show politeness. It is named after the now defunct airline Pan American World Airways, whose flight attendants would always flash every passenger the same perfunctory smile. Botox was introduced for cosmetic use in 2002. Chronic use of Botox injections to deal with eye wrinkle can result in the paralysis of the small muscles around the eyes, preventing the appearance of a Duchenne smile.
Keep smiling !!