Bimodal bilingualism: A unique window into the multilingual brain

Bilingualism provides a unique window into language processing and its underlying neurocognitive mechanisms. To date, the majority of bilingual research has been based on spoken‐language bilinguals who know two or more spoken languages. This chapter focuses instead on bilinguals who know both a signed and spoken language (speech‐ sign bilinguals). Research on speech‐sign bilinguals is a young, but quickly expanding area due to its potential as a valuable and unique window into the nature of bilingualism and the bilingual brain. By exploring differences between spoken‐language bilinguals and speech‐sign bilinguals, we can gain insight into how the brain represents and processes two languages in different sensorimotor modalities. Additionally, we can better understand the relationship between language and more general cognitive processes. This chapter contributes to the ongoing discussion by compiling and interpreting the findings that relate to speech‐sign bilingualism in the brain. Specifically, it provides an overview of the relevant research to date placed in a wider language con­ text by extending the study of bilingualism to languages in two different sensorimotor modalities, but at the same time focusing on results that provide critical insight into multilingualism more broadly.