Discovering Words in Speech

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

The Directorate of Social, Behavioral and Economic Sciences offers postdoctoral research fellowships to provide opportunities for recent doctoral graduates to obtain additional training, to gain research experience under the sponsorship of established scientists, and to broaden their scientific horizons beyond their undergraduate and graduate training. Postdoctoral fellowships are further designed to assist new scientists to direct their research efforts across traditional disciplinary lines and to avail themselves of unique research resources, sites, and facilities, including at foreign locations. This postdoctoral fellowship trains a young scientist exploring the early process of language learning by studying how young infants discover words in spoken language. This project also assesses how language experience affects the word discovery process by studying bilingual-learning infants and adults. By including infants, results from the project further knowledge about how learners acquire linguistic regularities from spoken language and provide insights into the mechanisms underlying early language development, both of which inform efforts to understand language impairments. Additionally, by including bilingual and adult populations, the project highlights how bilingualism changes the process of language acquisition, particularly early on in development. Beyond the scientific contributions, this fellowship also 1) supports the mentorship of undergraduate students from underrepresented backgrounds, 2) engages the local community, including populations typically underrepresented in research, through direct participation in the research and through presentation of the results by the fellow, and 3) supports the fellow?s outreach plan to broaden the participation of students from diverse backgrounds in the sciences. Finally, this fellowship supports the training and development of the fellow, a Mexican-American woman and first generation college graduate that holds a personal commitment to advancing underrepresented populations in STEM. Acquiring the words of the native language(s) typically begins by discovering them in speech. This process starts in the first year of life and is critical for language development. However, identifying the sounds that compose the words in spoken language is not trivial for the young child. The patterns that define words in natural languages are complex: they consist of multiple features and vary in their degree of reliability. Additionally, spoken words rarely occur in isolation, or with pauses to signal where they start and end. How do infants discover the structure of words given the complexities of spoken language? How does this process change as learners gain experience with language? To address these questions, this research manipulates the complexity of the language input, together with the language experience of the learner, to understand how infants discover words in speech. The studies in this project use an artificial language learning approach to study these questions. Study 1 examines how monolingual English learning infants (8 to 10 months of age) acquire a novel, complex word pattern embedded in fluent speech. Studies 2 and 3 assess how language experience affects learning by testing bilingual-learning infants (Study 2), and adults (Study 3). These studies outline how typically developing infants acquire linguistic patterns from spoken language, which is a necessary endeavor for understanding early language development. This project also informs efforts to understand communication and language disorders, and has the potential to be used in the future as a framework to study children with language and developmental delays.