This award was provided as part of NSF's Social, Behavioral and Economic Sciences Postdoctoral Research Fellowships (SPRF) program and supported by SBE's Science of Learning program. The goal of the SPRF program is to prepare promising, early career doctoral-level scientists for scientific careers in academia, industry or private sector, and government. SPRF awards involve two years of training under the sponsorship of established scientists and encourage Postdoctoral Fellows to perform independent research. NSF seeks to promote the participation of scientists from all segments of the scientific community, including those from underrepresented groups, in its research programs and activities; the postdoctoral period is considered to be an important level of professional development in attaining this goal. Each Postdoctoral Fellow must address important scientific questions that advance their respective disciplinary fields. Under the sponsorship of Dr. Casey Lew-Williams at Princeton University, this postdoctoral fellowship award supports an early career scientist investigating how bilingual children learn from the different speakers around them. Not all children growing up in bilingual homes become equally proficient in both their languages, and there is currently no consensus about the most effective way to promote bilingualism. This project is designed to address a common question raised by bilingual parents: is it easier for children to learn two languages when different people speak each languages Bilingual children, particularly Latinx children in the United States, face a uniquely challenging linguistic environment, as they must learn two languages in the same amount of time that monolingual children learn only one. Therefore, this work will provide insights that are both crucial for the scientific understanding of bilingualism and of great interest to parents, educators, and clinicians seeking to improve language outcomes for bilingual children.
It has been suggested that dual-language learning may be easier when each language can be associated with a particular speaker (e.g., one parent speaks one language; the other parent speaks the second). However, despite its intuitive appeal, there have been no direct empirical tests of this proposal. This research will assess whether reliable associations between speaker and language facilitate learning for Spanish-English bilingual infants and toddlers in both real and simulated bilingual environments. Study 1 will provide the first empirical test of whether bilingual and/or monolingual infants keep track of the languages used by new speakers. Studies 2 and 3 will then ask whether consistent speaker cues facilitate bilingual language learning. Study 2 will use a lab-based manipulation to test whether or not bilingual toddlers are better able to learn new labels produced by speakers who consistently use one language. Study 3 will extend these questions to real home environments and ask whether or not caregivers who consistently use one language have toddlers who show enhanced vocabulary development. Results from these studies will shed light on how bilinguals successfully navigate complex linguistic environments and provide insight into mechanisms of early learning. In doing so, this work could inform future practices and interventions designed to promote dual-language learning.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
