Mathematical development in Williams syndrome: A systematic review.
No math teaching method has been tested for Williams syndrome—lean on counting strengths and lighten visuo-spatial demands until research catches up.
01Research in Context
What this study did
Van Herwegen et al. (2020) hunted every paper on math skills in Williams syndrome. They read the studies, grouped them, and looked for patterns. The team wanted to see what we know and what we still don’t.
What they found
Almost every math area was weak—except quick counting of small sets. The papers were small, used different tests, and never explained why math is hard for these kids. No one has tested a math program for Williams syndrome yet.
How this fits with other research
Lemons et al. (2015) did the same kind of sweep for Down syndrome. They also found tiny, weak studies and zero solid lessons for teachers. The two reviews tell the same story: we can’t point to one proven math fix for either group.
Lanfranchi et al. (2015) showed that kids with Williams syndrome struggle most when they must hold and move spatial information at the same time. That memory gap lines up with Jo’s finding that visuo-spatial math tasks are especially hard.
Tonizzi et al. (2023) pooled 13 autism studies and saw lower math scores than in typical peers. Autism and Williams syndrome both show math trouble, but the reasons may differ—autism data point to language and working memory, while Williams data point to visuo-spatial blocks.
Why it matters
You can’t pick an evidence-based math curriculum for Williams syndrome yet. Start by checking if the child can do fast, small-number counts—that strength still stands. Build lessons that cut visuo-spatial load: use verbal chains, songs, and lined paper to keep numbers in rows. Track the data yourself until real trials arrive.
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02At a glance
03Original abstract
BACKGROUND: The current systematic review is the first to systematically explore and synthesis research to date on mathematical abilities in Williams syndrome (WS), a rare genetic disorder that results in an uneven cognitive profile. As mathematical development is complex and relies on both domain-specific and domain-general abilities, it is currently not clear what mathematical abilities have been examined in WS and also what the current gaps in this research area are. METHODS AND PROCEDURES: A total of 27 studies across 22 publications were identified through a systematic review search process. RESULTS: Overall, all mathematical abilities, except for simple counting and subitizing abilities, were reported to be impaired but in line with overall mental-age abilities. However, the literature to date has not established the underlying causes of these mathematical difficulties in WS. Some studies suggested that mathematical abilities in WS follow an atypical developmental pathway with a greater reliance on verbal abilities than in typical development but coupled with impaired understanding of counting and knowledge of the number system more broadly. However, most included studies used different assessments of mathematical skills and there is a lack of studies that have examined more than one particular aspect of mathematical development within the same study. In addition, studies have often included large age ranges and small participant samples, despite the known large individual variability in WS. CONCLUSION: Although we know mathematical abilities in WS are impaired, this area is under-researched and there is a lack of longitudinal studies that provide insight into the cognitive mechanisms that underpin mathematical development in WS. Therefore, there is a lack of an evidence-base to inform interventions or educational practice.
Research in developmental disabilities, 2020 · doi:10.1016/j.ridd.2020.103609