Author ORCID Identifier

Date Available


Year of Publication


Degree Name

Doctor of Philosophy (PhD)

Document Type

Doctoral Dissertation


Health Sciences


Rehabilitation Sciences

First Advisor

Dr. Judy Page

Second Advisor

Dr. Yang Jiang


There is a critical need for the development of ecologically valid clinical tools to assess real-life cognitive functioning in persons impacted by traumatic brain injury (TBI). Chronic cognitive impairments that are exacerbated by distractions are one of the core factors contributing to poor home and community re-integration post injury. Simulation-based digital platforms (i.e., virtual reality, augmented reality, and mixed reality) have become potential solutions for eliciting real-world cognitive performance in clinical settings. Yet, there is a paucity of research investigating the role and impact of distractions on cognition. As a result, there is no clear framework of measuring distractions to guide how they can be implemented into simulation platforms in a meaningful way.

This dissertation investigates four key problems associated implementing distractions into simulation-based clinical tools for assessing cognition. First, to elicit cognitive behavior that is parallel to real-world functioning, the selection of distractions requires an understanding how specific characteristics influence attentional encoding and information retrieval. Yet, there is an absence of research that outlines the impact of distractions on physiological, behavioral, and especially perceptual outcomes in clinical populations. Second, a lack of understanding of how distractions impact target clinical populations makes it challenging for researchers to select distractions that will elicit real-world cognitive functioning. Third, the development of a universal framework to guide the selection of distractions is critical for designing simulation programming with high levels of ecological validity and fidelity. Fourth, literature examining the impact of distractions does not include assessing the impact of specific distraction characteristics in both healthy and TBI populations.

The overall objective of this dissertation (1) examine how and what distractions have been utilized in simulation-based programs, (2) describe the perceived impact of distractions on performance, specifically in the workplace for persons with TBI, (3) expand upon the Limited Capacity Theory and sensory gating to develop a framework for examining specific characteristics of distractions (Elements of Distraction Framework (EDF)) and (4) evaluating the differences in physiologic, behavioral, and perceptual responses to distractions of varying complexity chosen from the EDF in persons with TBI and healthy controls. Together stages I, II, III, and IV of this dissertation address how simulation-based cognitive assessments can include distractions of varying complexity. Understanding the role and impact of distractions will inform and enhance tools for clinical assessments, facilitate accurate predictions of problem environments, and individualize patient treatment plans to maximize home and community re-integration.

Digital Object Identifier (DOI)

Funding Information

These studies were supported by the National Institutes of Health Clinical and Translational Science TL1 Pre-doctoral Training Grant (TL1TR001997) in 2021 and 2022.

The final study was supported by the RHB Pilot Study Funds in 2022.

Available for download on Thursday, May 01, 2025