Date of Award


Publication Type

Master Thesis

Degree Name




First Advisor

Towson, Shelagh,


Psychology, Developmental.



Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.


This study was designed to explore higher-order reasoning skills and executive-type functioning in children diagnosed with the syndrome of Nonverbal Learning Disabilities (NLD), and those evidencing Attention Deficit Hyperactivity Disorder (ADHD). To this end, Halstead Category Test (HCT) and Wisconsin Card Sorting Test (WCST) performances of 16 ADHD and 16 NLD children matched for verbal IQ and handedness were investigated. As predicted, the ADHD group made significantly fewer errors on the HCT than did the NLD group. In addition, the ADHD group significantly outperformed the NLD group on the majority of WCST variables with the exception of Failure to Maintain Set (FTMS) and Learning to Learn (LTL) scores. These findings suggest that while children with NLD exhibit difficulty reasoning abstractly and are perseverative in their approach to cognitive tasks, those with ADHD are quite adept at conceptual-level reasoning and display adequate cognitive flexibility. The results of this study support the notion that the behavior of individuals with NLD is guided more by internal mechanisms, whereas the behavior of individuals with ADHD appears to be more externally driven.Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2000 .H37. Source: Masters Abstracts International, Volume: 39-02, page: 0600. Adviser: Shelagh Towson. Thesis (M.A.)--University of Windsor (Canada), 2000.