Approximate additions and working memory in individuals with Down syndrome

Area of Science:

• Cognitive Psychology
• Developmental Neuroscience
• Genetics

Background:

• Individuals with Down syndrome (DS) often exhibit mathematical and working memory (WM) challenges compared to typically developing (TD) children.
• Research has extensively studied arithmetic and WM, but the role of WM in non-symbolic quantity processing remains underexplored.

Purpose of the Study:

• To investigate numerosity estimation abilities in individuals with DS compared to TD children matched for fluid intelligence.
• To examine the relationship between numerosity estimation tasks and verbal/visuospatial working memory in both groups.

Main Methods:

• Participants included children with DS and a control group of TD children.
• Numerosity estimation tasks involved single sets and sequentially added sets.
• Verbal and visuospatial working memory capacities were assessed.

Main Results:

• The DS group performed significantly worse on single-set numerosity estimation than the TD group.
• Performance on the addition numerosity task did not differ significantly between groups.
• For the DS group, success in the addition task correlated with working memory, especially the visuospatial component.

Conclusions:

• Numerosity estimation of single sets and set additions involve distinct cognitive processes.
• Working memory and arithmetic difficulties in DS are not universal and can be modulated by task demands.
• Individuals with DS can utilize working memory resources, particularly visuospatial WM, for addition-based numerosity estimation.