Attention Deficit Hyperactivity Disorder (ADHD) is one of the most prevalent conditions among school children. Executive function deficits representing difficulties in maintaining an appropriate problem set for the attainment of future goals are reported to be the major deficit in ADHD populations. There is a high rate of co-morbidity of learning disabilities and ADHD, with empirical evidence indicating an association with math and reading difficulties, but there is little research on the written expression of this population. There is a body of emergent research indicating that written expression is mediated by executive function. Written expression is a complex task that is affected by motivation, working memory, cognitive processes and long term memory, factors which are reported to be compromised in ADHD populations. This study evaluated the working memory and fluid reasoning in children with (combined and predominantly inattentive types) and without ADHD. Second, it explored the relationship between working memory and fluid reasoning on written expression in children with and without ADHD. Finally, the possible link between the executive functions of working memory and fluid reasoning, with written expression of children with and without ADHD was examined. The findings of this study indicate that children with the combined type of ADHD had lower written expression and working memory scores compared to children with the inattentive type of ADHD. The results of this study also indicated an association between disinhibition and working memory deficits on written expression performance. This research will serve to contribute to an understanding of the functional impact of ADHD on academic performance. Findings from this study could potentially help with interventions for deficits in written expression among school children.

The purposes of the present study were to investigate the relationship between short-term memory and reading in learning disabled and average learners, and to determine whether this relationship is different between ages 8 to 10 and ages 11 to 13 in these two populations. Studies have shown that children with learning disabilities tend to perform poorer on short-term memory tasks compared to children with no disabilities. The present study was conducted because the short-term memory component in the Stanford-Binet Intelligence Scale is new and it was felt that information regarding this test's usefulness with learning disabled students would be beneficial for individuals in the field of educational assessment. A total of 80 children, 39 average and 41 learning disabled were selected from the five public elementary schools that have learning disabilities classes in the Langley School District. For each group of learning disabled children selected from the learning disabilities class, an equal number of average learners was chosen from the same school. The children were divided into two age groups: 8- to 10-year-olds and 11- to 13-year-olds and then further divided into their two learning categories. Four short-term memory subtests of the Stanford-Binet Intelligence Scale: Fourth Edition: Bead Memory, Memory for Sentences, Memory for Digits and Memory for Objects and three reading comprehension subtests, from B.C. QUick Individual Educational Test, Peabody Individual Achievement Test and Test of Reading Comprehension respectively, were administered to all groups to measure short-term memory and reading. The Multivariate Analysis of Variance and the Pearson Product-Moment Correlation were used to analyse the data. Results showed that the average learners scored significantly higher than the learning disabled group in both short-term memory and reading. There was no interaction effect of learning group and age on reading or short-term memory. Significant relationships were found between short-term mmeory and reading for the average learning group but none was found for the learning disabled group. / Education, Faculty of / Graduate