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Exploring cognitive profiles of children with learning difficulties Open Access


Other title
Cognitive Profiles
Working Memory
Learning Disabilities
Type of item
Degree grantor
University of Alberta
Author or creator
Tonn, Ryan
Supervisor and department
Klassen, Robert (Educational Psychology)
Examining committee member and department
Leroy, Carol (Elementary Education)
Pei, Jacqueline (Educational Psychology)
Buck, George (Educational Psychology)
Alfano, Dennis (Psychology, University of Regina)
Mrazik, Martin (Educational Psychology)
Department of Educational Psychology

Date accepted
Graduation date
Doctor of Philosophy
Degree level
This study compares the role of cognitive processes in children diagnosed with learning disabilities (LD) through the traditional aptitude-achievement discrepancy model with students diagnosed on the basis of their low achievement alone. Historically, in North American settings, LD has been diagnosed when an individual’s achievement on standardized tests in reading, mathematics, or written expression is substantially lower than the expected level for age, schooling, and level of intelligence (American Psychiatric Association, 2000). As this conceptualization has come under increasing scrutiny, alternate identification methods such as the low achievement/non-discrepant method have been gaining support in the literature (e.g. Siegel, 1999; Stanovich, 2005). A secondary objective of this study is to determine whether identifiable differences exist between the cognitive profiles (WISC-IV) of students diagnosed with reading disability (RD) and mathematics disability (MD). This study also addresses whether the WISC-IV Working Memory Index can be used to differentiate between various categories of students with LD. The findings of this study indicate that the discrepant (DLD) and non-discrepant (NDLD) learning disability (LD) groups could not be distinguished by the WISC-IV Working Memory Index (WMI). Amongst the overall sample of students with LD, those with average or above working memory scores (high) could be differentiated from those with below average working memory scores (low) on the WISC-IV Perceptual Reasoning Index (PRI). Students with LD who had low WMI scores could also be differentiated from those with high WMI scores on four WIAT-II subtests. WMI scores could not be used to differentiate students with Reading Disability (RD), Mathematics Disability (MD) or Generalized Learning Disability (GLD). However, differences between these three LD groups were found on the WISC-IV Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), and marginally on the Processing Speed Index (PSI). Finally, the four WISC-IV Index scores were able to correctly predict group membership in the RD, MD, and GLD groups approximately 70% of the time.
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
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