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Enumeration skills in Down syndrome.

Francesco Sella¹, Silvia Lanfranchi, Marco Zorzi

¹Department of Developmental Psychology and Socialization, University of Padova, Via Venezia 8, 35131 Padova, Italy.

Research in Developmental Disabilities

|September 13, 2013

Summary

This summary is machine-generated.

Individuals with Down syndrome (DS) show specific difficulties with small number discrimination, impacting basic numerical skills. Their ability to grasp larger quantities and count appears delayed but largely intact.

Keywords:

Approximate number system Counting Down syndrome Numerical cognition Numerical development Object tracking system Subitizing Visual enumeration

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Area of Science:

Cognitive Psychology
Developmental Neuroscience
Genetics

Background:

Individuals with Down syndrome (DS) often experience mathematical challenges.
These difficulties may stem from global intelligence or unique cognitive profiles.
Investigating basic numerical skills in DS is essential for understanding these deficits.

Purpose of the Study:

To evaluate visual enumeration skills in individuals with Down syndrome.
To compare numerical discrimination abilities between DS and typically developing (TD) children.

Main Methods:

Two delayed match-to-sample tasks were administered.
Participants included individuals with DS and TD children matched for mental and chronological age.

Main Results:

Children with DS demonstrated a specific deficit in discriminating small numerosities (subitizing range) compared to both TD groups.
Discrimination of larger numerosities was comparable to mental age-matched TD children, but lower than chronological age-matched controls.
Counting was less fluent, but cardinality understanding appeared preserved in DS.

Conclusions:

DS individuals exhibit a deficit in the object tracking system for small numerosities.
Their approximate number system for larger numerosities shows typical but delayed development.
These findings highlight specific numerical processing challenges in Down syndrome.