Discrimination and imitation of facial expression by neonates.

Human neonates (average age, 36 hours) discriminated three facial expressions (happy, sad, and surprised) posed by a live model as evidenced by diminished visual fixation on each face over trials and renewed fixations to the presentation of a different face. The expressions posed by the model, unseeen by the observer, were guessed at greater than chance accuracy simply by observing the face of the neonate, whose facial movements in the brow, eyes, and mouth regions provided evidence for imitation of the facial expressions.