Rapid mouth covering is a body language consistent with a high empathy quotient. It is seen during moments of high surprise and disbelief - either with something very wonderful or very awful. Those who rarely do exhibit this and other gestures have relatively low empathy.
This phenomenon results from an emotional overload and is a nonverbal signal that the brain is rapidly processing new data. The emotional brain is essentially playing catch-up to what the logical brain already knows.
This image shows Ireen Wüst (Netherlands) during her gold medal award ceremony for the 3000 meter speed skating event. She became the first openly gay athlete to medal at the Sochi Olympic Games.
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