Sign linguistics is the scientific study of natural sign language. By sign language is meant a visual-gestural, non-vocal language primarily used by deaf people. Sign languages are not normally based on the spoken language of the surrounding hearing community. Sign languages developed historically among groups of deaf people, and they persist even though many deaf people have been taught to communicate orally, or have received cochlear implants.
Someone who studies sign language is called a sign linguist. Sign linguists can become member of the Sign Language Linguistics Society, whose main aim is the 'promotion of sign language research on an international scale, and the maintenance of high scientific and ethical standards of such research.'
Although the study of the gestural modality of language has a long history, the modern study of natural sign languages was initiated by Dutchman Bernard T.M. Tervoort (1920-2006) and the American scholar William C. Stokoe (1919–2000). The latter researched American Sign Language (ASL) while based at Gallaudet University (Washington D.C.) from 1955–1970. Stokoe's work focussed on the lexicon of ASL. This included a particular interest in the minimal contrastive units that occur in sign language. In line with the gestural components of sign languages, Stokoe referred to this analysis as cherology, a gestural parallel to the phonology, the study of the contrastive units of sound in spoken languages. While the term cherology is no longer current in sign linguistic circles, the key lexical features that Stokoe established for describing sign language lexis still form the basis for the elaboration of grammars in sign linguistics. The key lexical features used for describing a sign are:
Stokoe and colleagues developed a sign language transcription system that was based on this descriptive organisation of lexical form, and derivatives of that original transcription system continue to be in use today (in for example HamNoSys).
Early sign linguistic efforts, such as that by William Stokoe and his associates in Washington, and Mary Brennan and colleagues at Moray House School of Education in Edinburgh, were firstly aimed at establishing evidence for the claim that sign languages are language in all the senses that are associated with spoken language, and starting descriptions of the grammar and lexicon of national sign languages such as ASL (American Sign Language) and BSL (British Sign Language). Subsequently, much attention in sign linguistics turned to the three social institutions in which sign language is acquired and maintained: the family, the community, and the school. With respect to education in particular, sign linguistic evidence was needed first in order to establish and defend deaf pupils' right to acquire sign language as their first, natural language, as many generations had before them. And secondly, sign linguistic evidence was also needed in order to develop appropriate pedagogy and curricula that are needed in order to support sign language acquisition by native users, for second language learners, and for learning through sign language in compulsory and post-compulsory education.
Sign linguistic effort has subsequently also concentrated much attention on the particularly complex nature of simultaneous sign language interpreting and consecutive sign language translation that is needed in supporting effective communication between deaf and hearing participants in many situations—such as social service or health care contexts, conferences, theatre, education and work.
The sign linguistic description and analysis of sign languages has sufficiently advanced in order to enable the formal establishment of university-level courses in for example British Sign Language, as one choice among a range of modern language subjects that is available to students. However, what is lacking in the field is ready access to very large samples of sign language as it is used in everyday life by members of the language community. Sign linguists need such corpora in order to test the theoretical suppositions and frameworks that have been proposed to date, but also to document sign languages that are under threat from social and cultural change. This also includes recording sign language varieties and lexis that is no longer supported by new generations of sign language users.
Like the study of spoken languages, the study of sign languages knows many subsidiary fields and interests, but the main distinction that applies to mainstream linguistics also applies within sign linguistics. The first distinction is between those areas of study that focus on the structural organisation of the language as a symbolic system (ie, the study of grammar and lexis); and those areas of study that are concerned with sign language as it is acquired and practiced by people.
The study of grammar and lexis includes fields such as
The study of sign language as it is practiced by people includes for example,
Corpus sign linguistics is a practice and theory that can cover many, if not all, of the sign linguistic sub-disciplinary interests, but in particular it assumes that there is such a strong interaction between sign language structure and sign language performance that a scientific analysis of sign language structure and practice should be derived from, and must be confirmed by, sign language data collected from actual, 'real world' sign language performance in all the ordinary, typical and atypical situations of daily life.
Sign linguistics is to be distinguished sharply from sign semiotics, the study of the linguistic sign. Semiotics is the study of the relationship between the shape of words/signs (the signifier) and the concepts they refer to (the signified). This type of language modelling was originally developed by the Swiss linguist Ferdinand de Saussure. De Saussure thereby made a critical distinction between speech acts (fr: parole) and language system (fr: langue). Speech acts are actual language expressions—that what we hear, see, read—that are under the control of individuals, whereas the language system is an independent, largely self-regulating entity that is properly speaking the asset of a language community. Sign languages (signs) and spoken languages (words) are both amenable to semiotic analysis, but a key issue in semiotics that divides sign linguists from mainstream linguists is the supposed arbitrariness of the linguistic sign that Ferdinand de Saussure argued for in his semiotic theory of language.
A key claim in semiotics that contrasts it with theory in sign linguistics pertains to the notion of arbitrariness. According to de Saussure, the relationship between the shape and the reference of a word/sign must necessarily be unmotivated: without a direct connection between the two. Under this claim, there is no reason that the basic unit of heredity in living organisms, for example, should be called a 'gene'—the connection between the word gene and its meaning is a matter of agreement among users of English, soon after its use spread among biologists searching for the basic elements of natural life. However, the BSL sign for 'gene' (here taken from the Biology glossary for the national curriculum for Scotland) does seem to reveal something of what genes are thought to look like. In this case the relationship between the sign and the meaning seems motivated by an iconic relationship. Some sign linguists would argue that a considerable part of sign language lexis consists of such motivated signs, and that this is perhaps the attribute that distinguishes sign language lexis most from spoken language lexis at the level of pattern and organisation. Many attempts have been made to systematise the different types of motivation that occur in sign language morphology and lexis (e.g. Brennan 1990), including:
More recently, sign linguists have suggested that motivation occurs not only in lexis but also at higher levels of grammar, such as syntax, noting that it may well be the case that motivation is in fact a key organising principle in the grammar of sign languages.
The study of iconicity, which apears to put sign linguistic theory on a collision course with semiotic theory, is therefore a particularly productive area of sign linguistic research. While historically it has been the case that many mainstream linguists pointed to the 'arbitrariness principle' in defending their belief that sign languages were not natural languages (but at best advanced gestural systems), thanks to the combined mass of evidence collected by sign linguists on the complex patterning and many equivalencies in sign languages with spoken languages, that belief is no longer widely shared. Instead, sign linguists appear to be uniquely well-placed to make a major contribution to general linguistic theory, in re-assessing the theoretical assumptions that lie behind the notion of arbitrariness in language.
The book by Sutton-Spence and Woll (1999) provides an accessible introduction to sign linguistics.