Infants' Differential Reactions to Familiar and Distorted Faces

Four-month-old infants were presented four different three-dimensional representations of a human face: a regular face; a face in which the eyes, nose, and mouth were rearranged; a face with no eyes; and a blank face. Fixation times to the regular and rearranged face were equivalent, but smiling and large decreases in heart rate were significantly more frequent to the regular face. It was suggested that long fixations are ambiguous in meaning, for they can be elicited by stimuli that represent both emergent schema and partial violations of familiar schema. Assessment of other reactions, such as smiling and cardiac deceleration, furnishes important information on the infant's capacity for discrimination and allows the investigator to differentiate fixation in the service of assimilation from fixation in the service of reducing uncertainty.