Defense Date


Graduation Date

Fall 2012


Immediate Access

Submission Type


Degree Name



School Psychology


School of Education

Committee Chair

Ara Schmitt

Committee Member

Gibbs Kanyongo

Committee Member

Elizabeth McCallum


Mathematics, Neuropsychology, School-aged children


After multiple reviews of the literature, which documented that multiple cognitive processes may be involved in mathematics ability and disability, Geary (1993) proposed a model that included three subtypes of math disability: Semantic, Procedural, and Visuospatial. A review of the extant literature produced three studies that examined Geary's three subtypes, which provided some support for Geary's model. Given the paucity of research examining Geary's subtypes of math disability, this study aimed to add to the literature by exploring the presence of these three subtypes in a sample of school-aged children. The sample consisted of 60 participants (30 males, 30 females) ranging in age from 7 to 13. Participants were taken from the standardization sample of the NEPSY-II. Individuals with data on the NEPSY-II (Korkman, Kirk, & Kemp, 2007) and the Math Calculation and Math Reasoning subtests of the Wechsler Individual Achievement Test Second Edition (WIAT-II; Wechsler, 2001) were included in the primary analysis. Confirmatory Factor Analysis (CFA) results showed that the model consisting of select NEPSY-II subtests used to create Geary's three domains was a good fitting model. After creating domain scores for each participant, regression analyses were conducted in order to determine if Geary's three subtypes accounted for a significant amount of variance in math reasoning and math calculation performance. Results showed that the Semantic subtype did not contribute a significant amount of variance to numerical operations performance when examined in isolation. Hierarchical regression analysis, which consisted of entering the Semantic domain first and then adding the Procedural and Visouspatial domains simultaneously, showed that the model did not account for any variance in numerical operations performance. When all three domains were entered simultaneously, the Visuospatial domain was the only domain to account for a significant amount of variance in numerical operations performance. In terms of math reasoning, the Semantic domain was the only one to account for a significant amount of variance. The results of the current study are discussed within the context of Geary's theory and previous research related to Geary's theory. Finally, limitations, directions for future research, and implications are considered.