Numerical magnitude processing in children with mild intellectual disabilities.
Kids with mild ID have a delayed ‘number sense’—especially linking digits to quantities—so teach both the magnitude and the symbol connection.
01Research in Context
What this study did
Brankaer et al. (2011) tested how kids with mild intellectual disability (MID) judge number size. They used two quick tasks: one with pictures of dots and one with Arabic digits.
The team compared the MID group to two sets of peers: same-age kids and younger kids who matched their ability level.
What they found
Kids with MID were slower and less accurate when digits, not dots, were shown. Their dot scores looked like those of younger children.
The gap was largest on the digit task, showing the trouble is in linking symbols to amounts, not in seeing amounts alone.
How this fits with other research
Brankaer et al. (2013) ran the same kids two years later and added working-memory tests. The digit gap stayed even after memory was controlled, so the issue is not just poor memory.
Schwenk et al. (2017) pooled many studies and found the same pattern: kids with math problems are slow on digit comparison. The 2011 MID data sit inside their big negative effect.
Boudreau et al. (2015) looked at Down syndrome and saw no such digit deficit when mental age was matched. The clash makes sense: Down syndrome and MID follow different math-learning paths.
Why it matters
Screen digit comparison speed in your MID learners; it flags risk fast. Pair every symbol with its size (use number lines, dot-to-digit matches, and timed flash cards). Start at the student’s ability level, not grade level, and keep symbolic and non-symbolic drills side by side.
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02At a glance
03Original abstract
The present study investigated numerical magnitude processing in children with mild intellectual disabilities (MID) and examined whether these children have difficulties in the ability to represent numerical magnitudes and/or difficulties in the ability to access numerical magnitudes from formal symbols. We compared the performance of 26 children with MID on a symbolic (digits) and a non-symbolic (dot-arrays) comparison task with the performance of two control groups of typically developing children: one group matched on chronological age and one group matched on mathematical ability level. Findings revealed that children with MID performed more poorly than their typically developing chronological age-matched peers on both the symbolic and non-symbolic comparison tasks, while their performance did not substantially differ from the ability-matched control group. These findings suggest that the development of numerical magnitude representation in children with MID is marked by a delay. This performance pattern was observed for both symbolic and non-symbolic comparison tasks, although difficulties on the former task were more prominent. Interventions in children with MID should therefore foster both the development of magnitude representations and the connections between symbols and the magnitudes they represent.
Research in developmental disabilities, 2011 · doi:10.1016/j.ridd.2011.05.020