Comparison of Processing Speed and Working Memory in Students with Dyscalculia, Dyslexia, and Typical Development

Abstract

Cognitive abilities such as working memory and processing speed play a significant role in students’ learning processes and academic performance. Deficits in these abilities are often associated with learning disorders such as dyslexia and mathematics learning disorder (dyscalculia). The present study aimed to compare working memory and processing speed among elementary school students with dyscalculia, dyslexia, and typically developing peers in Tehran. This study employed an ex post facto (causal–comparative) design. The sample consisted of 75 male and female students from Grades 1 to 5 of elementary school during the 2021–2022 academic year in Tehran. Participants were divided into three groups: students with dyscalculia, students with dyslexia, and typically developing students. The groups were matched in terms of age, gender, grade level, and intelligence quotient (IQ). Working memory and processing speed were assessed using subtests of the Wechsler Intelligence Scale for Children – Fourth Edition (WISC-IV), standardized by Abedi and colleagues. Data analysis was conducted using one-way analysis of variance (ANOVA). The results of the ANOVA indicated a significant difference among the three groups in both working memory and processing speed (p < .001, df = 2). Specifically, students with dyscalculia and dyslexia demonstrated weaker performance compared to typically developing students; however, no significant difference was observed between the dyscalculia and dyslexia groups. The findings suggest that deficits in working memory and processing speed represent common characteristics among students with learning disorders. Therefore, designing and implementing educational and rehabilitation programs that focus on strengthening these cognitive abilities may contribute to improving the academic performance of these students.