1
Overview

Learning Areas

• The educational and social effects of language impairment.
• The child's language environment:
  • Learning more than one language
  • Accents and dialects of English.
• Typical language development:
  • Variation in rate of language development
  • External factors influencing variation
  • Intrinsic factors influencing variation.
• Speech and language impairment:
  • Speech and language impairment associated with identifiable conditions
  • Speech and language problems whose causes remain unexplained.

1.1 The Effects of Preschool Language Impairment

The ability to speak and understand is something we take completely for granted. Conversing with friends or partners, listening to the radio, talking on the phone, or telling stories to the children at bedtime are no more remarkable or reflected on than walking or eating, for most of us. We have engaged in these various linguistic activities for a long time - a good part of the competence that underpins our linguistic ability was in place by 5 years of age. After a few short years of childhood, at the time of school entry, each of us had a vocabulary of several thousand words. We could pronounce most of these accurately. We were able to organize words into coherent sentences, and deploy these sentences in conversations with parents, grandparents, siblings, and others, at the same time understanding what our interlocutors were saying to us. We were ready at that point to begin the long educational haul into literacy and numeracy, the skills on which full participation in our culture depends. And as we stepped outside the family unit into the wider society for the first time, we were able to use the language we had learned to make friends in school, and later in life to embark on relationships. What we learn about language in that first five years of our lives is an indispensable foundation for social well-being and educational progress. And for the vast majority it is acquired effortlessly. But if the process of language learning is constrained or restricted in any way in the preschool years, and delay or impairment results, the effects on educational advancement, and on socialization in childhood and beyond, can be severely inhibiting on life chances.

Research points to the continuing influence of slow or atypical oral language development on educational attainment, and on social facility. A long-term UK study of a group of children identified with language difficulties at the age of 4;0 years makes this clear. (The usual way of indicating age in the child population is illustrated here, by separating months from years with a semicolon.) Bishop and Edmundson (1987) identified a group of 87 4 year olds in the north-east of England who were language-impaired, and tested them on a range of linguistic abilities. The same children were retested 18 months later. At age 4, the children were classified as having impaired speech and language skills and normal nonverbal intelligence (the group with specific language impairment (SLI) - see Section 1.4) or having impaired speech and language skills, with verbal IQ at least two standard deviations below the mean (general delay group). The language impairment in 37% of the children had resolved when they were retested at age 5;6. These children were then studied again as teenagers, when 71 of the original group were contacted (Stothard et al., 1998). Children whose language problems had apparently resolved (at 5;6) did not differ from their peers on tests of vocabulary and language comprehension. Where they performed less well, however, was on tests of phonological processing and literacy skill. Those children who had continued to show significant language difficulties at the age of 5;6 in the original study had significant impairments in all aspects of spoken and written language functioning as adolescents. This was also true of children classified as having a general delay. These children fell further and further behind their peers in the development of their vocabularies over time.

It is apparent from these results that early language impairment can have serious long-term consequences educationally. Language impairment can also impact socially, with affected individuals prone to having poorer social skills and more limited peer relationships than their age-matched classmates in primary schools (Fujiki, Brinton, and Todd, 1996). Children with language impairment may also be at some risk of psychological problems: Snowling et al. (2006) reported on the rate of psychosocial difficulties in the sample identified by Bishop and Edmundson. They found that children whose language delay had resolved by 5;6 years tended to be free of problems. But for those whose language difficulties persisted through the school years, there was a raised incidence of attentional and social difficulties, associated with distinct language profiles. Attention problems were associated with a profile of expressive language difficulties; social difficulties were found in children with receptive and expressive language difficulties; and the group of children with both attention and social difficulties had low IQ as well as global language difficulties. Similarly, a follow-up study in early adult life of 17 individuals, who had been identified with a severe receptive language disorder in childhood, showed persisting language and literacy problems along with significant social difficulties and increased risk of psychiatric disorder, compared to controls (Clegg et al., 2005; see also St. Clair et al., 2011). At the extreme, limitations in language ability may be at least part of the reason young men find themselves in court or in prison. Bryan (2004) found that there was a much higher than expected prevalence of low linguistic ability in a cohort of young offenders in the United Kingdom. In a further study, of juvenile offenders (15-17 year olds; Bryan, Freer, and Furlong, 2007), 46-67% scored within the poor or very poor categories on sub-tests of the Test of Adult and Adolescent Language (TOAL-3; Hammill et al., 1994), as compared with 9% of the typical adolescent population. And of 100 young offenders completing custodial sentences in Victoria, Australia, 46 were classified as language-impaired (Snow and Powell, 2011).

These long-term educational and psychosocial consequences of preschool language impairment enjoin us to look more closely at the process of language development in typically developing (TD) children, and at the factors that can inhibit that development in their peers with language impairment, in the important period between birth and the age of 5. The last four decades have seen a burgeoning of research interest in children's language learning and there is no shortage of material to draw on in relation to typical or atypical development. In this volume we examine preschool language impairment in the light of typical language development, from an avowedly linguistic perspective. Children's language impairment is a topic that is rightly of interest to a number of disciplines besides linguistics, but we take the view here that it is linguistic description that is crucial in providing us with the basic anatomy of children's language behavior.

Throughout this text, we use typical language development in English as the standard against which the limitations of the child with language impairment are measured. The performance of TD children is taken as the benchmark against which the performance of the child with an impairment is assessed. Given that more than 90% of the world's children learn the speech and language (or languages) of their environment successfully by the time they go to school, there are two obvious questions to ask. How different from the linguistic progress of TD young children is that of individuals who are impaired? And what is it about children with language impairment that prevents them from making a success of language acquisition in the same time frame as the vast majority of their peers? We address these issues throughout the book. We begin, however, with some general considerations: about the environment in which children learn to speak; about variation in the rate of development in TD children; and about conditions with which speech and language impairments are associated.

1.2 The Ambient Language

Children learn to speak in a language community in a particular location, and in a specific social milieu. These contexts impact on the child in some ways that are obvious - children growing up in England learn English, children growing up in Norway learn Norwegian. But there can be more subtle effects of the linguistic environment. To take one example, the linguistic settings in which children find themselves may be more complex than those of us raised in monolingual environments may realize. Ireland is a country in which Irish is one of the official languages but where the majority of the population speak English - perhaps only 4% of the population use Irish regularly in daily life. As part of a government effort to maintain the Irish language, there are officially designated areas each referred to as a Gaeltacht in which Irish is the dominant language spoken - in these enclaves up to two-thirds of the population are Irish speakers. As well as receiving support for the maintenance of the Irish language, these areas also receive...