CompCog: Infant Vocalization as Foraging for Caregiver Responses

University Of California - Merced, Merced CA

Investigators

Abstract

During the first year of life, infants begin to vocalize, and their cooing and babbling become increasingly more sophisticated and complex, paving the way for speech. Infants' vocalizations often occur in strings or clusters of similar-sounding vocalizations. Caregivers frequently respond to babies' vocalizations even before they can talk, and adults vary their responses depending on the types of vocalization babies produce. These adult responses appear to influence babies' subsequent vocalizations. This research offers a new explanatory perspective on infant vocalization by borrowing ideas from what we know about how animals forage, systematically exploring an environment to find food. When foraging, animals strike a balance between revisiting familiar locations where food has been found and trying out new locations that may lead to undiscovered resources. This project will advance understanding of how infants refine their vocal abilities by considering prelinguistic infants as foragers who explore the range of possible vocalizations in search of interesting or useful feedback, including positive responses from adults. Daylong home audio recordings will be collected from English- and Spanish-learning infants at 3, 6, 9, and 18 months of age. Infant vocalizations will be automatically identified and analyzed acoustically, then situated in an abstract acoustic information space. For each region of acoustic space, the likelihood of receiving an adult response will be ascertained. Methods previously developed to analyze patterns of foraging for resources in physical space will be applied. Adult vocalization acoustics and their relationship to infant vocal foraging responses will be similarly analyzed. Computational models of infant and adult vocal foraging will be employed to explore possible mechanisms that underlie the observed temporal dynamics of infant and adult vocalizations over the course of the day. Vocal foraging measures will be tested for changes across age and with socioeconomic status. Whether foraging patterns during the first year predict speech-language abilities at 18 months will also be tested. The work has the potential to unveil new candidates for automatically obtainable markers that could be useful for early identification of children at risk for speech-language delays or disorders.