Bimodal Bilingualism: Code-blending between Spoken English and American Sign Language

The vast majority of bilingual studies involve two spoken languages. Such “unimodal” bilingualism automatically entails a severe production constraint because one cannot physically produce two spoken words or phrases at the same time. For unimodal (speech-speech) bilinguals, there is a single output channel, the vocal tract, for both languages. In contrast, for bimodal (speechsign) bilinguals, there are two output channels: the vocal tract and the hands. In addition, for unimodal bilinguals both languages are perceived by the same sensory system (audition), whereas for bimodal bilinguals one language is perceived auditorily and the other is perceived visually. In this article, we present a preliminary investigation of bimodal bilingual communication among hearing people who are native users of American Sign Language (ASL) and who are also native English speakers. First, it is important to emphasize that American Sign Language has a grammar that is independent of and quite distinct from English (see Emmorey (2002) for a review). For example, ASL allows much freer word order compared to English. English marks tense morphologically on verbs, whereas ASL (like many languages) expresses tense lexically via temporal adverbs. Conversely, ASL contains several verbal aspect markers (expressed as distinct movement patterns superimposed on a verb root) that are not found in English, but are found in many other spoken languages (e.g., habitual, punctual, and durational aspect). Obviously, ASL and English also differ in structure at the level of phonology. Signed languages, like spoken languages, exhibit a level of sublexical structure that involves segments and combinatorial rules, but phonological features are manual rather than oral (see Brentari (1998), Corina & Sandler (1993) for reviews). Finally, English and ASL differ quite dramatically with respect to how spatial information is encoded. English, like many spoken languages, expresses locative information with prepositions, such as “in,” “on,” or “under.” In contrast, ASL encodes locative and motion information with verbal classifier constructions. In these constructions, handshape morphemes specify object type, and the position of the hands in signing space schematically represents the spatial relation between two objects. Movement of the hand specifies the movement of an object through space (within whole-entity classifier constructions, see Emmorey, 2003). Thus, English and ASL are quite distinct from each other within phonological, morphological, and syntactic domains. In the current study, we chose to examine hearing ASL-English bilinguals because although Deaf signers are generally bilingual in ASL and English, many Deaf people prefer to read and write English, rather than use spoken English. Also, Deaf individuals do not acquire spoken English in the same way that a second language is acquired by unimodal bilinguals. For example, early speech bilinguals may be exposed to two languages in the home or one language may be used in the home and another in the community. In contrast, spoken language is not accessible in the environment of a deaf person and deaf children require special intervention, including training in speech articulation, speech perception, and lip reading, unlike hearing children acquiring a spoken language (see Blamey, 2003). Therefore, we examined hearing bilinguals who have Deaf parents for whom speech and sign are equally accessible within the environment. Bimodal bilingual children acquire a signed language and a spoken language in the same way that unimodal bilingual children acquire two spoken languages (Petitto, Katerelos, Levy, Gauna, Tetreault, & Ferraro, 2001; Newport & Meier, 1985) To our knowledge, this is the first study to examine bilingual communication in adults who acquired both signed and spoken languages naturally without explicit instruction. Hearing adults who grew up in Deaf families constitute an important bilingual community. Many identify themselves as