<p class="title">Mona Lisa's famed smile may be forced, according to a study which suggests that Italian polymath Leonardo da Vinci deliberately portrayed her that way.</p>.<p class="bodytext">Researchers at the St George's University of London in the UK set out to investigate the truth of Mona Lisa's expression and apply neuroscientific principles to the world's best-known painting.</p>.<p class="bodytext">They investigated the mechanism of the expression and used a 'chimeric face' technique; cutting the mouth in half and placing each half alongside its mirror image.</p>.<p class="bodytext">The two chimeric images were judged by a group of 42 healthy subjects and rated according to the expression perceived.</p>.<p class="bodytext">The subjects agreed that the left-left image showed happiness, while the right-right side image was less expressive, being perceived as neutral or even sad.</p>.<p class="bodytext">The research, published in the journal Cortex, concluded that the Mona Lisa is smiling asymmetrically.</p>.<p class="bodytext">The researchers, including Luca Marsili of the University of Cincinnati in the US and Matteo Bologna of Sapienza University of Rome, Italy, then applied their neuroscientific knowledge to this conclusion.</p>.<p class="bodytext">"According to the most accredited neuropsychological theories, if a smile is asymmetric it is usually non-genuine," said Lucia Ricciardi at St George's, University of London.</p>.<p class="bodytext">"While what we call a Duchenne' smile, a genuinely spontaneous smile, is bilateral and symmetrical. It's also characterised by upper face activation and that also doesn't seem to be the case in this portrait," Ricciardi said.</p>.<p class="bodytext">Recent research has suggested that asymmetric smiles can be a sign of insincerity or of a lie.</p>.<p class="bodytext">"Of course, we know that posing for a picture for many hours will result in a forced expression. But we also know that Leonardo was a master of 'sfumato' -- the technique of shading which is used to demonstrate expression," Ricciardi said.</p>.<p class="bodytext">"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.</p>.<p class="bodytext">"And he had this knowledge hundreds of years before Duchenne's work in the 1800s. So we have enjoyed hypothesising that this asymmetry was a deliberate action. What we still don't know is the reason that he portrayed her this way -- so her smile is as elusive as ever," he said.</p>
<p class="title">Mona Lisa's famed smile may be forced, according to a study which suggests that Italian polymath Leonardo da Vinci deliberately portrayed her that way.</p>.<p class="bodytext">Researchers at the St George's University of London in the UK set out to investigate the truth of Mona Lisa's expression and apply neuroscientific principles to the world's best-known painting.</p>.<p class="bodytext">They investigated the mechanism of the expression and used a 'chimeric face' technique; cutting the mouth in half and placing each half alongside its mirror image.</p>.<p class="bodytext">The two chimeric images were judged by a group of 42 healthy subjects and rated according to the expression perceived.</p>.<p class="bodytext">The subjects agreed that the left-left image showed happiness, while the right-right side image was less expressive, being perceived as neutral or even sad.</p>.<p class="bodytext">The research, published in the journal Cortex, concluded that the Mona Lisa is smiling asymmetrically.</p>.<p class="bodytext">The researchers, including Luca Marsili of the University of Cincinnati in the US and Matteo Bologna of Sapienza University of Rome, Italy, then applied their neuroscientific knowledge to this conclusion.</p>.<p class="bodytext">"According to the most accredited neuropsychological theories, if a smile is asymmetric it is usually non-genuine," said Lucia Ricciardi at St George's, University of London.</p>.<p class="bodytext">"While what we call a Duchenne' smile, a genuinely spontaneous smile, is bilateral and symmetrical. It's also characterised by upper face activation and that also doesn't seem to be the case in this portrait," Ricciardi said.</p>.<p class="bodytext">Recent research has suggested that asymmetric smiles can be a sign of insincerity or of a lie.</p>.<p class="bodytext">"Of course, we know that posing for a picture for many hours will result in a forced expression. But we also know that Leonardo was a master of 'sfumato' -- the technique of shading which is used to demonstrate expression," Ricciardi said.</p>.<p class="bodytext">"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.</p>.<p class="bodytext">"And he had this knowledge hundreds of years before Duchenne's work in the 1800s. So we have enjoyed hypothesising that this asymmetry was a deliberate action. What we still don't know is the reason that he portrayed her this way -- so her smile is as elusive as ever," he said.</p>