Eighteen-month-old infants show distinct electrophysiological responses to their own faces

Infants attain the developmental milestone of self-recognition around 18 to 24 months of age. At 18 months of age, half of the infant population typically shows signs of self-recognition in the classic mirror test. The current study examined the functional neural correlates of the perception of self in infancy. Eighteen-month-old infants observed photographs of their own face, the face of an unfamiliar infant, the face of their caregiver, and the face of an unfamiliar caregiver, while their EEG was registered. The results show that infants show an enhanced response to their own face compared to other faces. The N290, an established face-selective ERP component in infants, was larger for observation of their own face compared to others' faces. In addition to the EEG task, the mirror test was administered. Half of the infants in our sample recognized themselves in the mirror. However, there were no differences in the ERP responses between the infants who did and did not recognize themselves in the mirror. This suggests that a distinction between the neural response to self and to others does not necessarily express itself in self-recognition behavior.