Date of Award


Publication Type

Doctoral Thesis

Degree Name





Casey, Joseph




Although reading fluency has been identified as an important component of skilled reading, few studies have examined the underlying neural processes. The purpose of the current study was to compare the neural systems for reading in fluent and nonfluent beginning readers. The Goldberg and Costa (1981) theory of hemisphere differences provided a theoretical framework for conceptualizing the development of reading fluency. This theory proposes that the right hemisphere processes novel stimuli and assembles new descriptive systems while the left hemisphere utilizes fully formed and well-routinized codes, and that a right-to-left shift in hemisphere superiority occurs during skill development. Children between 6 and 7 years of age participated in an fMRI experiment. Low and high fluency groups were based on level of fluency in grapheme phoneme mapping. fMRI reading tasks were modeled on curriculum based measurement tests of reading fluency. Three different tasks involved letter phoneme, word spoken word, or picture spoken word matching. In high fluency as compared to low fluency beginning readers, there was greater activation in the left parietotemporal area during letter and word reading tasks, an area involved in phonological processing, grapheme phoneme mapping, and word decoding. Also, in the high fluency as compared to the low fluency group, there was greater activation in the left inferior frontal area during the word reading task, another area involved in phonological processing. Within the framework of the Goldberg and Costa theory, the greater left hemisphere involvement in the high fluency group may reflect the utilization of more routinized descriptive codes for phonological processing skills. There was greater activation in high fluency as compared to low fluency beginning readers in bilateral occipitotemporal areas during letter and word reading tasks, an area involved in visual recognition of letters and words. Within the Goldberg and Costa framework, this may reflect right hemisphere involvement in assembling a new descriptive system for visual recognition in the high fluency group, and a shifting in relative hemisphere superiority from the right hemisphere to the left hemisphere in the course of fluency development. In conclusion, the present study provides preliminary evidence that fluent and nonfluent beginning readers may engage neural systems for reading differently.