Are Emotions Contagious?
Mirror neurons fire in the brain when an act is both performed and observed. In a study where participants were shown faces for a mere 30 milliseconds, their faces activated the muscles to mimic that facial expressions even before they could recognize the expression.
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Key Facts In This Video
Humans mimic each other's facial expressions, postures, and elements of speech without realizing it. (0:18)
Human brains have "mirror neurons", neurons that fire when an action is performed and when it is observed. (0:46)
Some neuroscientists believe mirror neuron theory has been over-generalized. (2:34)