Doctoral Dissertation Research: Effects of non-verbal working memory and spoken first language proficiency on sign language acquisition by deaf second language learners

Gallaudet University, Washington DC

Investigators

Abstract

Deaf and hard of hearing (DHH) individuals experience substantial variability in exposure to a sign language. For example, more than 90% of DHH children in the US have hearing parents who do not know a sign language at the time of their DHH child’s birth. By the time these children are school-age, only 26% are using sign language regularly with their families at home and 53% are using some sign language at school. Consequently, a substantial number of DHH people are learning a sign language for the first time as young adults. Despite being one of the most common ways for DHH people to learn a sign language, researchers know very little about the factors that support second language learning success in this learning context. For example, proficiency in the first language and working memory are predictors of second language proficiency in other language learning contexts--are these predictors also important for DHH learners? Additionally, the quality and quantity of early language input that DHH people receive is highly variable--does this variation affect second language learning of a sign language? This doctoral dissertation study aims to (1) extend existing research on predictors of second language proficiency to a new learning context, DHH second language signers, and (2) investigate relationships between spoken first language proficiency, non-verbal working memory, and signed second language proficiency. This research conducts a mediation modeling study assessing spoken language reading comprehension and non-verbal working memory in DHH people who grew up using a spoken language as a primary language and started learning a sign language as young adults and investigate how these variables relate to sign language receptive comprehension. The results of this study will lead to more generalizable theories of second language learning that account for variability in the quality and quantity of early first language acquisition. The results also inform family and school language policy for DHH children as well as second language teaching curriculum and interpreting strategies for adult DHH second language signers. 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.