12- and 18-month-old infants follow gaze to spaces behind barriers.

Infants follow the gaze direction of others from the middle of the first year of life. In attempting to determine how infants understand the looking behavior of adults, a number of recent studies have blocked the adult's line of sight in some way (e.g. with a blindfold or with a barrier). In contrast, in the current studies an adult looked behind a barrier which blocked the child's line of sight. Using two different control conditions and several different barrier types, 12- and 18-month-old infants locomoted a short distance in order to gain the proper viewing angle to follow an experimenter's gaze to locations behind barriers. These results demonstrate that, contra Butterworth, even 12-month-old infants can follow gaze to locations outside of their current field of view. They also add to growing evidence that 12-month-olds have some understanding of the looking behaviors of others as an act of seeing.