What is the meaning of the smile? Recent research has shown that one type of smile — the enjoyment smile — seems to be associated with positive emotion, whereas other types of smiles are not.The facial expression commonly referred to as “a smile” is, in fact, not a singular category of facial behavior.
As far back as 1862, French anatomist G. B. Duchenne noted that the orbicularis oculi muscle, which surrounds the eye, is recruited in smiles that occur with spontaneously experienced enjoyment but not in smiles that are posed.Only in the last few decades have researchers gathered the empirical evidence to confirm Duchenne’s observation.
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