19 - Japanese Sign Language

Summary

Signed language is a natural language that uses a visual–gestural mode of communication, instead of the aural–oral mode used in spoken languages. Recent linguistic research on the structure of signed languages has revealed that they are full-fledged languages, comparable to spoken languages (Klima & Bellugi, 1979; Padden, 1988; Sandler, 1989; Lillo-Martin, 1991). From a linguistic and psychological point of view, it is important to investigate how deaf children acquire these languages. Through observing their developmental processes, we can obtain a more comprehensive picture of how human language is acquired.

In the field of sign linguistics, American Sign Language (ASL), the native language of North American deaf communities, has been studied most extensively thus far. ASL is just one language, different from other signed languages, for example, from Japanese Sign Language (JSL), the natural language used in the Deaf community in Japan. One example of this difference shows that in ASL, the dominant word order is subject–verb–object (SVO), while in JSL it is subject–object–verb (SOV). Some linguistic structures discussed below, however, are shared among different signed languages. Crosslinguistic comparison among signed languages as well as between signed and spoken languages is important, but has not been performed systematically so far, because no other signed languages than ASL have been investigated extensively.

This chapter discusses some important findings from recent research on JSL development. First, I present an overview of JSL structure.