Mirror-image responses and the development of self-recognition during the first two years of life
Video tape records were made of seventy-seven infants, ranging in age from one to 24 months, as each was exposed for three minutes to four different levels of mirror distortion. A mirror behavior checklist (Amsterdam 1968, 1972) was used to identify 34 possible behaviors. The range and complexity of mirror related activities increases significantly during the first two years of life, culminating in self-recognition by 52% of the subjects aged 19 to 24 months. All subjects responded equivalently to both the plain and distorted mirror images, suggesting that it is the general configuration of the face that holds intrinsic interest at these age levels. The prevailing view that the infant's perception is qualitatively similar to that of the adult was supported by this study.