Understanding the mental number line of children with Down syndrome
Background: Children with Down syndrome experience difficulties in learning mathematics, particularly in counting, discriminating quantities, and basic arithmetic. However, the sources of these difficulties remain a mystery. One possible factor may be the mental number line (MNL), our internal representation of numerical magnitude along a spatial continuum. The MNL underlies number sense, an ability to understand, represent, compare, and manipulate numerical quantities, which strongly relates to mathematics learning.
Aim: While the MNL has been widely studied in typically developing populations, little is known about how children with Down syndrome mentally represent numbers. This narrative literature review aims to synthesise existing research on the MNL in children with Down syndrome, examine methods used in these studies, and identify factors that may influence its development – age, educational experiences, general mathematics development, and cognitive and visual-spatial abilities. It also seeks to identify gaps and implications for future research and mathematics teaching.
Method/approach: A literature search was conducted using ERIC, PsycINFO, Scopus, Web of Science, and Google Scholar. Search terms included “mental number line”, “number line estimation”, “numerical magnitude representation”, “numerical estimation”, “spatial numerical association”, “spatial-numerical mapping” or “spatial numerical representation”, and “Down syndrome”. Peer-reviewed studies written in English were included.
Results/findings: Only three studies have examined the MNL in children with Down syndrome, all using number-to-position tasks. These studies found children with Down syndrome performed similarly to typically developing children matched on mental-age. However, findings are inconsistent regarding types of spatial-numerical representations used and their relationships with early numeracy skills and visuospatial abilities. Moreover, the absence of position-to-number tasks may limit understanding the MNL in this population, and other factors such as educational experiences, school and home mathematics activities, remain underexplored.
Conclusion: The review highlights significant gaps in knowledge of the spatial-numerical representations of children with Down syndrome and needs for further research. A better understanding of the MNL may contribute to numerical cognition theories and inform effective mathematics instruction and interventions for these children.
Implications for children and families: It will provide effective activities for parents supporting their children learning mathematics at home and help children gain confidence in learning numbers.
Implications for practitioners: It will be helpful for teachers in designing lessons or interventions and use effective strategies that best support their development.
Keywords: mental number line, children with Down syndrome, spatial-numerical mapping
This presentation relates to the following United Nations Sustainable Development Goals: