Autism and specific language impairment: diagnostic distinctions

Dorothy V. M. BishopDorothy V. M. BishopDorothy V. M. Bishop

Specific Language

Impairment

Autisticdisorder

The traditional view

Textbook view of specific language impairment (SLI)

• Selective problem with language development

• Other aspects of development – self help skills, socialisation, nonverbal abilities, motor skills – all developing normally

• Overall impression is that language is like that of a much younger child

Textbook view of autistic disorder

• Difficulties are pervasive and affect three areas of development (the autism ‘triad’)• Communication• Social interaction• Behaviour/interests – repetitive and restricted

• Qualitative differences from typical development

autisticdisorder

communicationsocial

interests

The autistic triad

However!

Some children don’t fit neatly into these categories

Evidence for development of autistic features in some children with

receptive language impairments

Bartak, L., Rutter, M., & Cox, A. (1975). A comparative study of infantile autism and specific developmental receptive language disorder: I. The children. British Journal of Psychiatry, 126, 127-145.

Selection criteria: Bartak et al, 1975

• Impaired verbal comprehension • Boys, aged 5-10 years• Nonverbal IQ of 70+• Normal hearing• No neurological disease

19 autisticdisorder

23 receptivelanguagedisorder

5 mixed

Very similar language findings for autistic and language-impaired

proportion

Bartak et al: nonlanguage

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

difficult adaptation to new situations

quasi-obsessional activities

ritualistic activities

resistance to change

attachment to odd objects

lacks imaginative play

proportion

autistic receptive SLI

But very different behaviour findings for autistic and language-impaired

Bartak et al: language use

0 0.2 0.4 0.6 0.8 1

pronoun reversal (ever)

echolalia (ever)

stereotyped utterances (ever)

metaphorical language (ever)

inappropriate remarks

no spontaneous chat

fails to respond to questions

never used gesture

proportion

autistic receptive SLI

And very different in language use for autistic and language-impaired

autistic-like behaviours seen in SLI at follow-up

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

stereotyped utterances

metaphorical language

no group participation

fails to show sympathy

stereotyped mannerisms

lacks imaginative play

rituals

proportion

autistic receptive SLI

Cantwell, D., et al. (1989). Infantile autism and developmental receptive dysphasia: a

comparative follow-up into middle childhood. J Autism and Developmental Disorders, 19, 19-31.

But SLI start to show more autistic behaviours at follow-up in middle childhood

Howlin et al, 2000

• Follow-up of original sample into adulthood

• Some of the original language-impaired sample show more evidence of social and behavioural problems, similar to autism

Howlin, P., Mawhood, L., & Rutter, M. (2000). Autism and developmental receptive language disorder - a comparative follow-up in early adult life. II. Social, behavioural, and psychiatric outcomes. Journal of Child Psychology and Psychiatry, 41, 561-578.

Example of man with receptive SLI diagnosis in childhood

"In all aspects of self-care he was entirely independent and he could use a telephone and manage his finances himself. Most of his spare time was spent pursuing his preoccupation with buses and his less intense interest in CB radio. He spent a lot of time hanging around bus stations, going on bus journeys when he could afford it, and looking at bus magazines. His social overtures were somewhat limited and he would speak if spoken to but would not make the first move. There were two friends that he visited regularly; one shared his interest in buses, the other was interested in CB radio. These relationships were clearly selective, did involve some apparent pleasure in each other's company, and some sharing of confidences, but there was still nonetheless a slightly odd quality to them because of their restricted range of interests. He did not appear to be lonely." (p. 384).

Autistic-like impairments in communication and social

interaction in some cases of language impairment

Bishop & Norbury, 2002

• Study of children receiving special educational provision for language/communication disorders

• Direct observation, language assessment and parental report

• Significant numbers of children with autistic-like language features but who did not meet criteria for autism on ‘gold standard’ autism assessments

Bishop, D. V. M., & Norbury, C. F. (2002). Exploring the borderlands of autistic disorder and specific language impairment: A study using standardised diagnostic instruments. Journal of Child Psychology and Psychiatry, 43, 917-929.

autisticdisorder

communicationsocial

interests

Fractionating the autistic triad

Elements of the triadthat form autistic disordercan be dissociated: many children with just one or two areas of difficulty

Diagnostic dilemmas

Diagnosis complicated by:

Changing clinical picture with age

Difficulties in evaluating autistic-like symptoms in children with receptive language problems

Diagnostic dilemmas, ctd.

Categorical diagnosis not well suited to capturing clinical variation

Textbook cases of SLI and autism are easy to recognise but many children less clearcut

No clear dividing line between SLI and autism Current deliberations for revisions of DSM and ICD

diagnostic classifications: Considering removing requirement of third triad element

(repetitive behaviour) for ASD diagnosis Considering adding new category of ‘social communication

impairment’ that would incorporate intermediate cases