ATYPICAL LANGUAGE DEVELOPMENT

1. ATYPICAL LANGUAGE DEVELOPMENT LANGUAGE DEVELOPMENT AND BLINDNESS LANGUAGE DEVELOPMENT AND MENTAL RETARDATION

2. LANGUAGE DEVELOPMENT AND BLINDNESS Why is language development in blind children be any different from language development in sighted children? Blind children’s access to nonverbal communication and to nonverbal context of communication is limited to what can be perceived through the senses other than vision. Many arguments assert that language development builds on nonverbal communication (e.g. Bates, Camaioni, & Volterra, 1975; Bruner, 1977) and that language development depends on accessing the meaning of sentences from the observable non-linguistic context.

3. LANGUAGE DEVELOPMENT AND BLINDNESS ◊ It is more difficult for blind children to achieve joint attention because the usual routes of the eye gaze and pointing are blocked. ◊ Phonological development is also affected by blindness. -Blind children make more errors than sighted children in producing speech sounds that have highly visible articulatory movements.

4. LANGUAGE DEVELOPMENT AND BLINDNESS ◊ Blind children have been reported to have fewer words for objects that can be seen but not touched and more words for things associated with auditory change (Bigelow, 1987). ◊ Several studies have indicated that blind children are less likely than sighted children to overgeneralize their words (A. Mills, 1993). In fact, blind children often fail to appropriately generalize words, using new words as names for specific references rather than as names of categories (Dunlea, 1989)

5. LANGUAGE DEVELOPMENT AND BLINDNESS ◊ There is a delay in blind children’s acquisition of verbal auxiliaries (Landau & Gleitman, 1985). ◊ With respect to style of language use, several studies have reported that blind children show a greater use of social routines and unanalyzed, formulaic speech that sighted children do (Dunlea, 1984; Kekelis & Andersen, 1984; A. Mills, 1993; Perez-Pereira & Castro, 1992; Peters, 1994).

6. LANGUAGE DEVELOPMENT AND BLINDNESS ◊ Blindness affect conversational interaction. ◊ Blind children who have no other handicapping condition babble, produce first words, produce word combinations, and acquire syntax and morphology on essentially the same timetable as do sighted children.

7. Language Development and Mental Retardation Definition: “significantly subaverage general intellectual functioning…that is accompanied by significant limitations in adaptive functioning” (American Psychiatric Association, 1994)

8. Language Development and Mental Retardation The question of how language development is affected by mental retardation is of interest for obvious applied reasons and because it allows researchers to ask how general intellectual functioning is related to language development.

9. Language Development and Mental Retardation If acquiring language is just one more thing humans do with their general intellectual capacity, then impairment in general intellectual capacity should impair language development, and it should do so to the same degree that general capacities are impaired. On the other hand, if language is a separate capacity, then there should be some independence or dissociation of general intelligence and language ability.

10. LANGUAGE DEVELOPMENT AND MENTAL RETARDATION • Language Development in Children with Down Syndrome • Language Development in Children with Williams Syndrome • Case Studies of Individuals with Mental Retardation Who Have • High-Level Language Skills

11. Language Development in Children with Down Syndrome Down syndrome is a chromosomal abnormality present in approximately 1 in 800 newborns, that accounts for roughly one third of the moderately to severely mentally retarded population (Rondal, 1993) Both the severity of mental retardation and the language development of persons with Down syndrome vary considerably, and some individuals with Down syndrome achieve typical adult-level linguistic competence. However, most do not (Fowler, Gelman, & Gleitman, 1994), and despite the individual differences that exist, it is possible to describe some general characteristics of language development in individuals with Down syndrome.

12. Language Development in Children with Down Syndrome In general, for children with Down syndrome, language is more impaired than other cognitive functions, grammar is particularly affected among components of language, and production deficit exceed comprehension deficits (Abbeduto et al., 2003; Beeghly & Cicchetti, 1987; Singer Harris, Bellugi, Bates, Jones, & Rossen, 1997; J.F. Miller 1992).

13. Language Development Courses in Children with Down Syndrome The onset of canonical babbling appears to be delayed by about 2 months, and phonological development after infancy is substantially delayed. Phonological processes that are typical of normally developing toddlers continue into adolescence and adulthood (Chapman, 1995). Most adults with Down syndrome have some difficulty producing intelligible speech, although the source of the problem is not clear (J.F. Miller, 1992).

14. Language Development Courses in Children with Down Syndrome Lexical development starts late and proceeds slowly in children with Down syndrome. They typically produce their first word around 24 months- approximately 1 year later than typically developing children but on schedule, so to speak with respect to mental age. By the time children with Down syndrome are 6 years old, they are more than 3 years behind typically developing children in mental age, and their productive language lags even behind their mental age.

15. Language Development Courses in Children with Down Syndrome A child with Down syndrome who is 6 years old and has a mental age of 3-year-old child (Abbeduto & Murphy, 2004). Comprehension vocabulary is more on par with mental age. Perhaps to compensate for their limited vocabulary, children with Down syndrome produce communicative gestures more frequently than typically developing children (Singer Harris et al.,1997)

16. Language Development Courses in Children with Down Syndrome Grammatical development is the area of language most affected by Down syndrome. Both production and comprehension are delayed relative to mental age, and grammatical development shows an extremely protracted course of growth. Children with down syndrome cover the same course of grammatical development as typically developing children do, but the children with Down syndrome may take 12 years to do what most children accomplish in 30 months (Fowler et al., 1994)

17. Language Development Courses in Children with Down Syndrome There are conflicting findings with respect to the course of grammatical development in individuals with Down syndrome after adolescence. Fowler et al. report that expressive language plateaus at the age of 12: Stage III, or an MLU of about 3.0, is as far as they can get. Longitudinal research has, in contrast, found that individuals with Down syndrome continue to grow in expressive language, including syntax (Chapman, Seung, Schwartz, & Kay-Raining Bird, 2000)

18. Language Development Courses in Children with Down Syndrome Communicative development and pragmatic development appear to be particular strengths of children with Down syndrome. Beginning at about 6 months, children with Down syndrome vocalize and engage in mutual eye contact (e.i., primary intersubjectivity) more than typically developing infants do. However, children with Down syndrome have trouble achieving secondary intersubjectivity, which requires engagement with another person about some third entity.

19. Language Development Courses in Children with Down Syndrome Adolescents with Down syndrome have difficulties using language for social interaction (Abbeduto & Murphy, 2004), they perform poorly in referential communication tasks, have difficulty with the kinds of form-function mapping that need to be controlled in order to mark politeness appropriately, and have difficulty controlling reference in narrative production (Rosenberg & Abbeduto, 1993)

20. Case Study of Individuals with Mental Retardation who have High-Level Language Skills “D.H.” She has a cognitive deficit so severe that she is unable to put three pictures in correct order to tell a story, she has difficulty naming the seasons of the year, and her IQ has been measured at 44. Yet D.H. can talk up a storm. Not only does she talk a great deal, her speech is fluent and grammatically correct.

21. Speech sample from D.H., a woman with chatterbox syndrome and a measured IQ of 44 Researcher:So how long have you been here then? D.H.: Two and a half years. Researcher:Uh-huh D.H.:And Dad’s getting fed up with moving around. He thinks it’s time that I settle down-to school, which is fair enough. To him, it… he feels it’s going to ruin my whole life if I don’t settle down sometime. Researcher:Uh-huh

22. Speech sample from D.H., a woman with chatterbox syndrome and a measured IQ of 44 D.H.: So I’m gonna have to, at some point settle down, somewhere. Researcher:Uh-huh D.H.:Somehow, Mum didn’t mind me moving about, but Dad objected to it because he knew it was bothering me and it was bothering my school work.

23. Case Study of Individuals with Mental Retardation who have High-Level Language Skills “Laura” At the age of 16, she performed at the level of 3-to 4-year-old child on most cognitive tests, but she was able to produce sentences such as these: She does paintings, this really good friend of the kids who I went to school with last year and really loved. He was sating that I lost my battery powered watch that I loved.

24. Case Study of Individuals with Mental Retardation who have High-Level Language Skills On the basis of cases such as D.H. and Laura, some have argued that the ability to acquire grammar is separate from other nonlinguistic cognitive functions, and in fact, is separate from the mental ability that underlies the acquisition of semantics and pragmatics; this is the argument for the modularity of syntax (Cromer, 1994; Curtis, 1988; Yamada, 1990)