Bimodal bilinguals master languages in two modalities, spoken and signed, and can use them simultaneously due to the independence of the articulators. This behavior, named code-blending, is one of the hallmarks of bimodal bilingualism. Lexical experiments on production and comprehension in American Sign Language/English showed that blending is not cognitively costly and facilitates lexical access. In this work, we replicated the blending advantage in lexical comprehension for hearing bimodal bilinguals with two other language pairs, French Sign Language (LSF)–French and Italian Sign Language (LIS)–Italian, and we explored whether the facilitation is also found at the sentential level. Results show that blended utterances for languages with incongruent word order like LIS–Italian were processed slower than monolingual utterances, while no difference was found when the word orders were congruent (LSF–French). We discuss these findings in light of linguistic theories of syntactic structure derivation in bimodal bilinguals.

Mouthings, the spoken language elements in sign language discourse, are typically analysed as having a redundant, one-on-one relationship with manual signs, both semantically and temporally. We explore exceptions to this presupposed semantic and temporal congruency in a corpus of spontaneous signed conversation by deaf users of Sign Language of the Netherlands (NGT). We identify specifying mouthings (words with a different meaning than the co-occurring sign), solo mouthings (uttered while the hands are inactive) and added mouthings (words added to a signing stream without their corresponding sign), and make a sentence-level analysis of their occurrences. These non-redundant mouthings occurred in 12% of all utterances, and were made by almost all signers. We argue for the presence of a code-blending continuum for NGT, where NGT is the matrix language and spoken Dutch is blended in, in various degrees. We suggest expansion of existing code-mixing models, to allow for description of bimodal mixing.

In analyzing code-switching in spoken languages, Chan (2003, 2008) proposes that only functional heads with their associated language determine the order of the complement. In this paper, we examine whether Chan's analysis can account for code-blending in Hong Kong Sign Language (HKSL) and Cantonese by a deaf child (2;0.26–6;6.26) and three deaf adult native signers. HKSL and Cantonese differ in head directionality so far as the functional elements of modals, negators, and auxiliaries are concerned. They are head-final in HKSL but head-initial in Cantonese. The HKSL–Cantonese code-blending data in this study largely conform to Chan's analysis, where the order of the complement is determined by which language the functional head appears in. However, code-blending the functional heads of a similar category in both languages leads to either order of the complement. Also, the deaf child's apparent violations of adult HKSL grammar reveal crosslinguistic influence from Cantonese to HKSL during code-blending.