It Sounds the Way It's Spelled: Orthography Effect Mechanisms in Persons with Aphasia

Abstract

The goal of this dissertation was to find converging evidence from behavioral and neuroimaging analyses of the mechanisms of orthographic integration with general language processes. By examining orthography effects, covert influences of orthography on non-written tasks, in participants with aphasia, we attempt to elucidate the nature of orthographic integration, and provide additional evidence that may assist in refining assessment and treatment of reading and language impairments. We determined that the mechanisms of orthographic access underlying two types of orthography effects were separable. In addition, we found that the mechanism of one type of orthography effect may be different depending on the modality of stimulus input. We conclude that there are multiple, separable mechanisms by which orthography influences general language processes. We also speculate on the exact mechanisms of orthographic integration by examining current and past evidence, and we postulate a new mechanism based on lexical access of orthography in tasks with pictorial stimuli. This dissertation provides important information that informs cognitive models of reading and language for future linguistic studies. In addition, our research provides support to the notion that neural models are useful tools to inform those cognitive models.