Sequential and simultaneous processing abilities of high-functioning autistic and language-impaired children.
Low sequential scores on the WISC-R may reflect language problems more than autism itself.
01Research in Context
What this study did
The team gave 30 high-functioning autistic kids and the kids with language delays the same WISC-R sub-tests.
They looked at two kinds of thinking: step-by-step (sequential) and all-at-once (simultaneous) processing.
All children had IQs above 70 and spoke in sentences.
What they found
Both groups scored lower on step-by-step tasks than on all-at-once tasks.
The gap was the same size for autistic kids and for kids with language delays.
Language problems, not autism, seemed to drive the weakness.
How this fits with other research
Vugs et al. (2013) later showed the same weakness in a big meta-analysis of kids with specific language impairment.
Their pooled data prove the deficit is real and not just a fluke in the 1991 sample.
Evers et al. (2014) found autistic kids struggle with global visual tasks, but that study used fragmented pictures, not step-by-step logic.
The two findings do not clash; one points to visual binding issues, the other to ordered thinking issues.
Why it matters
When you see low scores on WISC-R sub-tests like Digit Span or Coding, pause before blaming autism.
Check the child’s language scores first. If language is weak, the sequential dip may be language-driven, not autism-driven.
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02At a glance
03Original abstract
Investigated the Sequential and Simultaneous processing distinctions of high-functioning autistic children and children with a developmental receptive language disorder (DRLD). Twenty autistic subjects and 20 DRLD subjects were matched on age and gender, and compared to each other on their Sequential and Simultaneous processing abilities utilizing the K-ABC and selected subtests of the WISC-R. Results showed that both groups manifested a relative sequential processing deficit. However, the groups did not differ significantly on their overall sequential and simultaneous processing capabilities relative to their degree of language impairment. The application of the sequential and simultaneous processing model to the WISC-R provided consistent convergent and discriminant validation for the assessment of these processes with the WISC-R.
Journal of autism and developmental disorders, 1991 · doi:10.1007/BF02206872