In the study, 76 blind Judo competitors and 82 sighted competitors were photographed immediately after important matches, when recieving a medal and standing on the podium.

The researchers found that whether the athletes became blind later in life, were born blind or were sighted made no difference to their facial expression.

“We also see that blind athletes manage their expressions in social situations the same way sighted athletes do." claims author of the study David Matsumoto, PhD, of San Francisco State University.

The difference between a genuine smile showing uncontrolled elation and a polite smile covering up sadness or contempt, Matsumoto said, “is a genuine smile engages the muscles that lift the corner of the mouth upward and laterally and includes the eyes (orbicularis oculi muscles). One of the telltale signs for this is crow’s feet by the eyes. A social or lying smile does not use these upper face muscles but instead uses the muscles in the lower part of the face. People smile like this to be socially gracious in uncomfortable situations.”

These findings may offer new ways of understanding the mechanisms by which individuals learn to regulate their emotional displays, suggesting that visual observation may not be necessary for such learning to occur, said Matsumoto. “This raises questions of what mechanism controls individuals, blind or not, to learn to manage their emotional expressions,” he said.

Reference

"Spontaneous Facial Expressions of Emotion of Congenitally and Noncongenitally Blind Individuals,” David Matsumoto, PhD, San Francisco University and Bob Willingham, PhD, Center for Psychological Studies, Journal of Personality and Social Psychology, Vol. 96, No.1.

Source: Adapted from materials provided by EurekAlert (Press Release)