Infant–caregiver interaction is essential for early vocal development

Abstract

Vocal interactions between an infant and a caregiver facilitates early vocal development, and one of the issues is how an infant learns to vocalize the caregiver’s native language. Explanation of this ability of infant is attempted by many theories which advocate imitation based on acoustic matching. However, the infant's and caregiver's speech are quite different in their acoustic qualities. Therefore, it cannot be fully explained by imitation. In this talk, I assume that the interaction itself may have an important role to play, but the mechanism is still unclear. I review studies addressing this topic based on explicit interaction mechanisms using computer simulations and/or real vocal robots. Modeling approaches are classified into four categories: (a) motor control ability develops through self-monitoring of vocalizations, (b) statistical estimation of caregiver’s vowel categories from caregiver’s vocalizations, (c) self-organization of shared vowels through imitative interaction, and (d) whole dynam...