Date of Award

Spring 2021

Project Type

Thesis

Program or Major

Communication Sciences and Disorders

Degree Name

Master of Science

First Advisor

Amy Ramage

Second Advisor

Kirrie Ballard

Third Advisor

Kathryn Greenslade

Abstract

Aphasia is the breakdown of language comprehension and production due to an acquired brain injury of the left hemisphere. Investigation of the neurological underpinnings of aphasia have advanced from post-mortem investigation of specific regions in the 1800s to the utilization of brain imaging technology to understand brain networks. These approaches have helped us to appreciate the reorganization of the brain and its networks post stroke, particularly as it relates or is modified for adequate versus impaired performance. Research into neuroplastic changes can elucidate differences between healthy and lesioned brains. Furthermore, identification of adaptive (or maladaptive) neuroplastic changes can also inform diagnostics or aid in monitoring the neuroplastic effects of evidence-based treatment. This study utilized resting state functional MRI to characterize graph theory metrics of language (LN) and cognitive control networks (frontoparietal, FPN) in 21 persons with aphasia (PWA) and 18 healthy controls (HC). This study further investigated the relationship between strength of connectivity and semantic access and errors in PWA during a picture description task. When comparing resting state network connectivity of the LN in PWA vs. HC, many edges (10/14) and node degree hubs (3/3) were common to both groups for the LN, suggesting that an inherent network that remains relatively intact even post-stroke. Analyses yielded similar results for resting state FPN network connectivity with common edges and node degree hubs. When investigating correlations between network edges and language measures, correlations between FPN edges and CIU’s and retracing suggested the importance of right hemisphere and ‘healthy’ edge integrity.

Download

Share

COinS