01/30/2015 08:17 am ET Updated Jan 30, 2015

The Technology That Unmasks Your Hidden Emotions

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Paul Ekman, perhaps the world’s most famous face reader, fears he has created a monster.

The 80-year-old psychologist pioneered the study of facial expressions in the 1970s, creating a catalog of more than 5,000 muscle movements to show how the subtlest wrinkling of the nose or lift of an eyebrow reveal hidden emotions.

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