ABSTRACT
Most children learn language successfully and most adults find no difficulty in maintaining the language they have learned. But any speech community (at least in the developed world, which is as far as our knowledge extends) will contain a small proportion of children for whom language learning is considered to present particular problems. And it seems reasonable to suppose that adults in any speech community are prone to the cerebrovascular accidents, or stroke, which we know result in the disruption of language. Because language is so intimately concerned with other areas of intellectual functioning in both development and breakdown, and because many of the identifiable causes of language impairment are medical, language pathology cannot be the sole province of the linguist or phonetician. Nevertheless, recent years have seen a steady infiltration of linguists and phoneticians into the field of speech and language disorders. Of course an interest by linguists into this area is not new: Jakobson's hypothesis concerning phonological breakdown in aphasia is over forty years old (Jakobson 1968 (1941)). But in the last decade we have seen much more than the occasional foray. There is, particularly in the English-speaking world, a quite widespread application of phonetics (including instrumental techniques) and phonology, of descriptive grammatical frameworks, of grammatical theory, and of concepts from semantics and pragmatics, to a variety of disorders and their remediation, and an extensive literature is developing. The term ‘clinical linguistics’ is often now used to refer to this new field (see Crystal 1981), suggesting an emerging identity. In this chapter we will illustrate how the main areas of linguistics are applied across a varied range of impairments. Before considering the application of linguistics to language disorders in any detail, however, we need to examine the contexts in which this application is made, so as to assess how the contribution from linguistics fits into the overall framework of language disorder.
