Date of Degree

2010

Document Type

PhD diss.

Degree Name

PhD (Doctor of Philosophy)

Department

Psychological and Quantitative Foundations

First Advisor

Elizabeth M. Altmaier

Second Advisor

Lynn C. Richman

Abstract

Word-retrieval and rapid naming abilities play an important role in language processing and cognitive development. Researchers have demonstrated that early language difficulties may lead to later reading impairments and several decades of research has convincingly demonstrated that rapid automatized naming is a powerful predictor of concurrent and future reading development. As a result, researchers have argued that naming and reading tasks involve some shared cognitive processes.

Language and reading deficits have implications for academic success and self-esteem, particularly during childhood. Hence, the identification of children at-risk for developing reading impairments is an important task for educators and clinicians. Debates still exist about whether rapid naming difficulties reflect simple delays in language acquisition resulting from processing speed and/or attention problems or are suggestive of abnormalities in underlying cognitive processes. While the co-occurrence of rapid naming deficits and reading impairments is well established in the literature, few studies have explored the presence of Dysnomia without reading impairment.

The current study examined the nature of expressive language deficits for Dysnomic children with and without impaired reading by incorporating multiple neuropsychological measures. In a sample of children (N=104) between the ages of 6 and 12 years, performance differences were specifically investigated on measures of verbal fluency, confrontation naming, and rapid naming, as well as visual and verbal sequential memory. The impact of a concurrent diagnosis of a primary attention deficit was also examined within the context of cognitive performances.

Results of the current study indicated that a concurrent diagnosis of AD/HD significantly impacted performance on measures of verbal fluency and confrontation naming. When comparing the neurocognitive profiles of these children, those with Dysnomia performed significantly better on reading-related tasks and worse on a measure of visual sequential memory. No significant differences were found between groups on other neuropsychological measures, yet performances were consistently below average for children in both groups. Overall, findings revealed that children in both groups displayed similar neurocognitive profiles. However, children diagnosed only with Dysnomia were significantly younger than children with both Dysnomia and Dyslexia. Findings from this study have implications for research and intervention with school-aged children. Treatment approaches targeting reading fluency and automaticity may be particularly helpful for children with Dysnomia, in addition to intervention programs which integrate fluency-based with phonological-based treatment.

Pages

ix, 150

Bibliography

137-150

Copyright

Copyright 2010 Robyn Ann Howarth