The nature of early self-recognition

In studies of mirror-self-recognition subjects are usually surreptitiously marked on their head, and then presented with a mirror. Scores of studies have established that by 18 to 24 months, children investigate their own head upon seeing the mark in the mirror. Scores of papers have debated what this means. Suggestions range from rich interpretations (e.g., the development of self-awareness) to lean accounts (e.g., the development of proprioceptivevisual matching), and include numerous more moderate proposals (e.g., the development of a concept of one's face). In Study 1, 18-24-monthold toddlers were given the standard test and a novel task in which they were marked on their legs rather than on their face. Toddlers performed equivalently on both tasks, suggesting that passing the test does not rely on information specific to facial features. In Study 2, toddlers were surreptitiously slipped into trouser legs that were prefixed to a highchair. Toddlers failed to retrieve the sticker now that their legs looked different from expectations. This finding, together with the findings from a third study which showed that self-recognition in live video feedback develops later than mirror selfrecognition, suggests that performance is not solely the result of proprioceptive-visual matching.

Mirror self-recognition beyond the face

Three studies (N=144) investigated how toddlers aged 18 and 24 months pass the surprise-mark test of self-recognition. In Study 1, toddlers were surreptitiously marked in successive conditions on their legs and faces with stickers visible only in a mirror. Rates of sticker touching did not differ significantly between conditions. In Study 2, toddlers failed to touch a sticker on their legs that had been disguised before being marked. In Study 3, having been given 30-s exposure to their disguised legs before testing, toddlers touched the stickers on their legs and faces at equivalent levels. These results suggest that toddlers pass the mark test based on expectations about what they look like, expectations that are not restricted to the face.