Steven L. Elmlinger

My main research focus concerns the role of parent-child interaction in early acquisition of speech and language. I study human infants' early language and communicative development with a particular interest in how mechanisms of perception give rise to learning in social environments. I investigate this question in three lines of research:

Infants change their own learning environment. What is the function of infants’ immature behavior in early development? Our recent findings suggest that infants’ immature vocalizations elicit simplified linguistic responses from their caregivers (Elmlinger, Schwade, & Goldstein, 2019a, 2019b; Elmlinger, Park, Schwade, & Goldstein, 2021). Already by 5 months of age, infants expect that their own vocalizations will elicit responses from their caregivers (Elmlinger, Schwade, Vollmer, & Goldstein, 2023). By 9 months, infants regularly incorporate the content of parents’ speech which is temporally organized around infants’ own vocalizations. Our results suggest that by vocalizing, infants can regulate the amount of information in their language environment. The implications of this work are that infants’ immature vocal behavior functions to change the immediate environment in ways that make learning easier to do.

Across multiple languages, infants change their own learning environment. Do infants in non-English language environments also simplify the linguistic content of immediate caregiver responses to their babbling? Using large-scale corpora analysis and simulation of parent-child vocal turn-taking, we found that the simplification of linguistic content in response to immature child vocalizations is a strong and stable pattern across multiple languages (Elmlinger, Levy, & Goldstein, in press). By vocalizing in a social environment, children across multiple language environments elicit speech structure from their caregivers which is more favorable for learning (Elmlinger, Goldstein, & Casillas, 2023). These findings point to a stable cross-linguistic strategy that enables efficient language learnability for children first breaking into the structure of their ambient language.

Feedback guides the efficiency of avian and human vocal sequences. Across many species that communicate acoustically, distinct vocal elements are often strung together, one after another, forming a vocal sequence. In both zebra finches and humans, mature vocal sequences are produced quickly and efficiently. In a comparative analysis of vocal development in human infants and songbirds, we found evidence that immature learners use social guidance to navigate the transition into more efficient vocal communication (Elmlinger, Carouso-Peck, Wilk, & Goldstein, in prep). In both taxa, we observed: 1) a positive relationship between adult feedback to immature vocalizations and the efficiency of vocal sequences 2) a positive relationship between vocal sequence efficiency and communicative maturity. These findings point to a parallel learning mechanism underlying vocal development across two distantly related species.