Bimodal bilingualism

Bimodal bilingualism refers to an individual or community's bilingual competency in at least one oral language and at least one sign language—oral and sign are the modes to which "bimodal" refers. A substantial number of bimodal bilinguals are Children of Deaf Adults or other hearing people who learn sign language for various reasons. Deaf people as a group have their own sign language and culture, but invariably live within a larger hearing culture with its own oral language. Thus, "most deaf people are bilingual to some extent in [an oral] language in some form". In discussions of multilingualism in the United States, bimodal bilingualism and bimodal bilinguals have often not been mentioned or even considered, in part because American Sign Language, the predominant sign language used in the U.S., only began to be acknowledged as a natural language in the 1960s (In discussions of bimodal bilingualism in the U.S., the two languages involved are generally ASL and English). However, bimodal bilinguals share many of the same traits as traditional bilinguals (those with competency in at least two spoken languages), as well as differing in some interesting ways, due to the unique characteristics of the Deaf community.

To be defined as bilingual, an individual need not have perfect fluency or equal skill in both languages. Bimodal bilinguals, like oral-language bilinguals, exhibit a wide range of language competency in their first and second languages. For Deaf people (the majority of bimodal bilinguals in the U.S.), level of competency in ASL and English may be influenced by factors such as degree of hearing loss, whether the individual is prelingually or post-lingually deaf, style of and language used in their education, and whether the individual comes from a hearing or Deaf family. Regardless of English competency in other areas, no Deaf individual is likely to comprehend English in the same way as a hearing person when others are speaking it because only a small percentage of English phonemes are clearly visible through lip reading. Additionally, many Deaf bilinguals who have fluency in written English choose not to speak it because of the general social unacceptability of their voices, or because they are unable to monitor factors like pitch and volume.

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