Numerical and area comparison abilities in Down syndrome.
Area and number comparison skills in Down syndrome match mental-age level—use area as a friendly on-ramp to numeracy lessons.
01Research in Context
What this study did
The team asked kids with Down syndrome to look at two pictures. One picture showed two sets of dots. The other showed two colored shapes. The kids pointed to the bigger set or the bigger shape.
A second group of kids without Down syndrome did the same tasks. Both groups had the same mental age. The study checked if Down syndrome changed how kids see number and area.
What they found
Kids with Down syndrome picked the bigger area just as well as their mental-age peers. They also picked the bigger number set just as well. Area was a little easier for both groups.
The study shows that basic “which is more” skills are intact in Down syndrome when you match mental age.
How this fits with other research
Margari et al. (2013) looked at the same population two years earlier. They found a gap in subitizing—naming small sets of one to three dots fast. The two studies sit side-by-side: quick naming is weak, but careful comparing is fine.
Lanfranchi et al. (2015) took the good news and ran with it. They built a short number game for kids with Down syndrome. After a few weeks the trained group beat untrained peers in math and logic. The 2015 assessment gave the green light that the skill is there to train.
Lanfranchi et al. (2021) moved the training into living rooms. Parents ran a 20-minute computer game twice a week. Kids kept their gains for three months. Each study extends the last: first show the skill, then teach it, then send it home.
Why it matters
You can stop assuming that Down syndrome means broken number sense. Start tasks at the child’s mental age, not birth age. Use area games first—they’re easier—and bridge to numbers. If the child can point to the bigger slice of pizza, you have an entry point for teaching “more” and “less” with dots, coins, or tally marks.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Run a quick “Which pizza slice is bigger?” trial, then swap the slices for dot arrays and keep the same “point to more” instruction.
02At a glance
03Original abstract
Individuals with Down syndrome (DS) have great difficulty in learning mathematics. In recent years, research has focused on investigating whether precursors of later mathematical competence, such as estimating and comparing numerosities, are preserved in DS. Although studies have suggested a strong relationship between the ability to compare continuous quantities (e.g., area of an object) and that of comparing numerosities, it is still unknown whether this ability is preserved in DS. This study investigated the abilities of individuals with DS to compare area and number and contrasted them with those of two control groups of typically developing individuals. Participants were 16 individuals with DS, 16 typically developing individuals matched by mental age (MA group), and 16 typically developing individuals matched by chronological age (CA group). All participants performed two eye-tracking tasks: an Area Comparison Task (ACT) and a Number Comparison Task (NCT). Stimuli in the two tasks differed in the same ratio to enable comparison of individual performance across both tasks. The results showed that in general, the performance of the three groups was better in the ACT than in the NCT. Critically, performance of individuals with DS in both tasks was consistent with that of individuals with the same MA. The study shows that the abilities to compare area and numerosity are both preserved in DS, and that individuals with this syndrome, like typically developing individuals, show better performance in comparing area than number.
Research in developmental disabilities, 2015 · doi:10.1016/j.ridd.2015.05.008