We always admire Mona Lisa because it has the most famous smile in the world. However, in a recent announcement recently proved the exact opposite.
The thing is, that smile may not be authentic at all, based on new research. And it might have even been the artist's intention.
Three neuroscientists, including Luca Marsili of the University of Cincinnati, have been studying Mona Lisa's smile to find out the truth behind it. They've discovered that, rather than implying she had some kind of secret, the smile is actually a forced expression and Leonardo da Vinci deliberately portrayed her that way.
"Our results indicate that happiness is expressed only on the left side," the authors wrote in a new paper. "According to some influential theories of emotion neuropsychology, we here interpreted the Mona Lisa asymmetric smile as a non-genuine smile, also thought to occur when the subject lies."
With Lucia Ricciardi from the St George's University of London and Matteo Bologna from the Sapienza University in Rome, Marsili studied the iconic smile using the "chimeric face" technique. They cut Mona Lisa's smile exactly in half and placed each piece alongside a mirror image of itself. They then asked 42 people to judge which of the six basic emotions each side expressed.
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Thirty-nine of the participants said the left half of the smile indicated happiness, while none could say the same of the right. In fact, 35 of them felt that they understood the right side smile to indicate disgust or sadness, or was just neutral.
The researchers also pointed out that the painting's smile depicts no upper-face muscle activation. This is called a Duchenne smile, where the cheeks rise and the eyes crinkle, and it's considered a sincere smile. By contrast, Mona Lisa has neither of those.
According to the authors, that means Mona Lisa's smile "reflects a non-genuine emotion and is thought to occur when the subject lies." Which is understandable really, given that no one could find it easy posing with a smile for hours on end while sitting for a portrait.
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"We know that Leonardo was a master of 'sfumato'-the technique of shading which is used to demonstrate expression," Ricciardi said. "He deliberately raised her left lip, as if to paint a smirk. He would have known that curving the lip on both sides and adding folds around the eyes would have shown a genuine smile, and he had this knowledge hundred of years before Duchenne's work in the 1800s."
So the question then is, why did da Vinci deliberately give his subject a forced smile? Well, we still have no idea. "While the Mona Lisa smile continues to attract the attention of its observers," the researchers wrote, "the true message it conveys remains elusive and many unsolved mysteries remain to be elucidated, perhaps via the knowledge of emotion neuropsychology."
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