Dynamic Facial Expressions of Emotion Transmit Hierarchical Information over Time

Facial expressions have evolved to be a near-optimal system of communication. Jack et al. show that dynamic facial expressions of emotion transmit a developing hierarchy of information over time. Early on, they transmit few, biologically rooted signals (such as eyelid raising), which gives rise to specific confusions (such as fear or surprise); more complex signals support the discrimination of all six e