A MULTIMETHOD EXAMINATION OF PSEUDONEGLECT AND AGING
Date
2019-01-31
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0000-0001-8851-4476
Type
Thesis
Degree Level
Doctoral
Abstract
Neurologically healthy adults display a reliable leftward perceptual bias during visuospatial tasks, and this bias appears to change with age. The goal of the current research was to provide an examination of age-related differences in the expression of pseudoneglect and explore whether a shift in the perceptual bias with age was associated with daily activities, such as driving. Chapter 1 provides an overview of hemispatial neglect and pseudoneglect. Chapter 2 reports on results of an Internet-based survey in which the developmental trajectory of pseudoneglect was investigated using the greyscales task, which is known to generate a stronger and more consistent leftward bias among adults than similar tasks. Age was found to be positively correlated with a leftward bias, and the oldest age group exhibited a significantly stronger leftward bias compared to the youngest age group. Chapter 3 outlines the results of a systematic review that was used to synthesize previous literature that has examined the association between age and pseudoneglect. The systematic search revealed that five different tasks have been used to examine pseudoneglect in younger and older adults, and that participants over 60 years of age have demonstrated inconsistent perceptual biases (e.g., enhanced leftward bias, suppressed leftward bias, and rightward bias). The objectives of the quasi-experiment reported in Chapter 4 were to replicate the findings presented in Chapter 2 in a laboratory environment, and further understand influential methodological (e.g., task demands) and individual factors (e.g., normative and non-normative aging) on performance. Again, older adults, whether healthy or displaying symptoms of cognitive impairment, exhibited a leftward bias comparable to younger adults on the greyscales task, but demonstrated a weaker leftward bias on the landmark task. The study presented in Chapter 5 explored the potential association between age-related differences in pseudoneglect and driving by examining location of impact data associated with crashes and near crashes retrieved from a database of real-world driving behaviour. In contrast with results from laboratory environments, age was not associated with location of impact during crashes and near crashes, and overall, crashes were 1.41 times as likely to occur on the left compared to the right side of participants’ vehicles. Chapter 6 summarizes the findings presented in prior chapters and notes potential future directions. Together, the results of both laboratory and naturalistic studies outlines the variability in pseudoneglect demonstrated by healthy older adults, informs future research regarding the importance of task demands and non-normative aging, and highlights the potential implications of lateral perceptual biases.
Description
Keywords
Pseudoneglect, Aging, Greyscales Task
Citation
Degree
Doctor of Philosophy (Ph.D.)
Department
Psychology
Program
Psychology