Art is supposed to be a highly subjective experience, contradicting science's focus on objective conclusions. But a team of neuroscientists believe they've arrived at a definitive interpretation about Leonardo da Vinci's famous Mona Lisa. According to their research, the subject in the painting is putting on a forced smile.
In a paper published in the journal Cortex, researchers from the U.S. and Europe set out to examine the smirk of the painting's subject, believed to be a woman named Lisa Gherardini, whose husband commissioned the painting as a gift. First, they created chimeric images of the Mona Lisa's expression by bisecting her face and mirror-imaging the left or right sides to create full smiles. Then, they asked 42 study participants to describe the images from a list of six different emotions. Thirty-nine said the left side was expressing happiness. No one in the group labeled the right side as appearing happy. Most said it was neutral, while five said it was actually displaying disgust.
Conclusion? The happiness of the smile appeared only on the left, and was therefore asymmetrical and "non-genuine."
Coupled with their observation that the face of the Mona Lisa appears expressionless around the cheeks and eyes, the researchers surmised that the woman in the painting was appearing to be insincere. They argue that Leonardo likely took his model's blank expression and added a slight smirk on the left side: perhaps Gherardini simply couldn't maintain a pleased expression while sitting for the duration of the work. They also speculate that Leonardo may have known an asymmetrical smile was thought to be non-genuine and purposely depicted it to draw more reactions out of the painting's viewers.
It's also possible that none of these theories is correct. Like any great work of art, its meaning could remain enigmatic for another five centuries at least.