How Caregiver's Anticipation Shapes Infant's Vowel Through Mutual Imitation

The mechanism of infant vowel development is a fundamental issue of human cognitive development that includes perceptual and behavioral development. This paper models the mechanism of imitation underlying caregiver-infant interaction by focusing on potential roles of the caregiver's imitation in guiding infant vowel development. Proposed imitation mechanism is constructed with two kinds of the caregiver's possible biases in mind. The first is what we call "sensorimotor magnets," in which a caregiver perceives and imitates infant vocalizations as more prototypical ones as mother-tongue vowels. The second is based on what we call " automirroring bias," by which the heard vowel is much closer to the expected vowel because of the anticipation being imitated. Computer simulation results of caregiver-infant interaction show the sensorimotor magnets help form small clusters and the automirroring bias shapes these clusters to become clearer vowels in association with the sensorimotor magnets.