Mathematical difficulties in developmental coordination disorder: Symbolic and nonsymbolic number processing.
Kids with DCD fall behind on every type of number task, so check math skills early and teach both nonsymbolic and symbolic formats.
01Research in Context
What this study did
Gomez et al. (2015) compared kids with developmental coordination disorder (DCD) to same-age peers without motor problems. They gave both groups two kinds of number tasks: nonsymbolic (dot arrays) and symbolic (digits).
Kids also solved single-digit addition problems while the team timed them.
What they found
Children with DCD scored lower on both dot and digit tasks. They were also slower at simple addition.
The gap shows that motor problems often ride along with hidden math struggles.
How this fits with other research
Chan et al. (2013) saw a split picture in Chinese first-graders: dyscalculia hurt nonsymbolic skills only, while low numeracy hurt symbolic skills only. Alice’s DCD group failed at both, so the double hit may be unique to DCD.
Lanfranchi et al. (2022) found no number-line gap in Down syndrome when kids were matched for mental age. Alice’s DCD kids lagged even against same-age peers, hinting that DCD math deficits are larger or less age-flexible.
Lanfranchi et al. (2015) used only number-line tasks in Down syndrome and tied performance to mental age. Alice widened the lens by testing both symbolic and nonsymbolic formats, giving a fuller map of weak spots to target.
Why it matters
If you serve a client with DCD, do not assume math will develop naturally. Screen early with quick dot and digit comparison tasks. Add extra time for arithmetic drills and embed motor-friendly math tools like large foam numbers or touch screens. Target both nonsymbolic sense and symbolic fluency; the deficit lives in both places.
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02At a glance
03Original abstract
At school, children with Developmental Coordination Disorder (DCD) struggle with mathematics. However, little attention has been paid to their numerical cognition abilities. The goal of this study was to better understand the cognitive basis for mathematical difficulties in children with DCD. Twenty 7-to-10 years-old children with DCD were compared to twenty age-matched typically developing children using dot and digit comparison tasks to assess symbolic and nonsymbolic number processing and in a task of single digits additions. Results showed that children with DCD had lower performance in nonsymbolic and symbolic number comparison tasks than typically developing children. They were also slower to solve simple addition problems. Moreover, correlational analyses showed that children with DCD who experienced greater impairments in the nonsymbolic task also performed more poorly in the symbolic tasks. These findings suggest that DCD impairs both nonsymbolic and symbolic number processing. A systematic assessment of numerical cognition in children with DCD could provide a more comprehensive picture of their deficits and help in proposing specific remediation.
Research in developmental disabilities, 2015 · doi:10.1016/j.ridd.2015.06.011