Language and Cognitive Development in Bimodal Bilingual Deaf Children in Hearing Families: Three Case Studies

We investigated aspects of language and cognitive development in three bimodal bilingual deaf children in hearing families. Some previous research finds cognitive delays for deaf children, which may be due to an early lack of access to language input. Studies of children having strong early language access through parental use of American Sign Language (ASL) support the hypothesis that language delays are behind such cognitive delays. We ask whether hearing parents who are novice learners of ASL provide sufficient support for early language and cognitive development. The three case studies in this report used both ASL and English, with support for ASL development provided by our ASL specialist. We assessed the children's general cognition, executive function, ASL vocabulary, English vocabulary, and overall language ability in both ASL and English. We found strong language development outcomes and correspondingly, age-appropriate cognitive development. These results are consistent with the conclusion that novice signer parents can support their children's development as ASL-English bilinguals, establishing a strong foundation for further cognitive and linguistic growth.