Development of recognition memory for faces during infancy

Abstract

An increasing number of studies have demonstrated that even newborn infants have the ability to recognize faces they have seen previously. Here, findings on recognition memory for faces during infancy were reviewed. First, the findings in newborn infants were summarized, including memory both for personally familiar faces (e.g., their own mother's face) and unfamiliar faces. Recent findings suggest that the differential pattern of preference between mother's face recognition and unfamiliar face recognition is due to the difference in the stimulus characteristics during the familiarization phase. Second, the total looking time during the habituation/familiarization phase were examined, which enabled infants to recognize faces in various previous studies. This examination revealed a clear developmental trend that the looking time during the learning phase decreased within a few months after birth for studies using the familiarization method. On the other hand, there was no clear trend across the studies using the infant-controlled habituation method. Although studies using looking time measures suggest exposure to a face for at least several seconds is required for successful face recognition, studies using nonbehavioral measures suggest the possibility that infants recognize face seen only for less than a second. Finally, the findings on long-term memory for faces during infancy were summarized. Although studies on this topic are relatively scarce, a few existing findings suggest that facial memory acquired in the latter half of the first year could be retained for a year or longer.