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Numerical estimation in individuals with Down syndrome.

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Area of Science:

  • Cognitive Psychology
  • Developmental Psychology
  • Neurodevelopmental Disorders

Background:

  • Numerical estimation is crucial for mathematical development.
  • Children with Down syndrome (DS) often exhibit challenges in numerical cognition.
  • Understanding the factors influencing numerical estimation in DS is important for targeted interventions.

Purpose of the Study:

  • To investigate numerical estimation abilities in children with Down syndrome (DS).
  • To determine if performance patterns in DS are linked to experience (age), cognitive level, or specific impairments.
  • To compare numerical estimation in DS with typically developing (TD) children.

Main Methods:

  • Administered Siegler and Opfer's (2003) number-to-position task.
  • Included 21 children with DS and two control groups of TD children.
  • Matched control groups for mental and chronological age.

Main Results:

  • Children with DS showed numerical estimation patterns more similar to TD children of the same mental age than chronological age.
  • The developmental transition from logarithmic to linear estimation patterns in DS mirrored that of younger TD children.
  • Linearity in estimation was associated with cognitive level in children with DS, but with experience level in TD children.

Conclusions:

  • Numerical estimation development in DS is more closely aligned with cognitive maturity than chronological age.
  • Cognitive level, rather than experience, appears to be the primary factor influencing estimation linearity in DS.
  • Findings suggest distinct developmental trajectories for numerical estimation in DS compared to TD children.