Assessment of visual performance during walking

Vision and locomotion are crucial for humans. Traditional (stationary) vision tests are unlikely to reflect how vision functions dynamically. The walking-induced movements of head and eyes challenge vision in different ways, and because of age-related changes in various systems, including the visual system, acquiring accurate visual information of both stationary and moving objects may become challenging with age. New techniques for assessing dynamic visual performance with simultaneous evaluation of head and eye kinematics may help in comprehending visual capabilities during walking, with the potential to identify age-related changes specifically present in dynamic conditions. This thesis presents new techniques for the assessment of dynamic vision: a task for studying the visual limitations of reading from a handheld smartphone during walking; a novel method, “Assumed-gaze approach”, to determine gaze location/orientation during walking without an eye-tracker; and a visual acuity (VA) test for the assessment of static and dynamic VA, with simultaneous study of the walking-induced head kinematics. Key findings from this research include: phone-reading performance decays at increasing walking speeds, explained by increased motion-variability between the head/eyes and the handheld phone. The Assumed-gaze approach shows good agreement with the gaze measures from a head-mounted eye-tracker, validating this technique for assessing assumed-gaze location/orientation. VA determined with the new test developed here is similar to the VA obtained using the goldstandard chart. This new test is hence valid for assessing static and dynamic VA. However, the dynamic conditions studied did not reveal age-related changes in vision nor association with head kinematics.

Grantor dc:publisher.institution

University of Bradford

Year dc:date.issued

2023

Author dc:creator

• Barañano, Alejandro R.

Advisors dc:contributor.advisor

• Barrett, Brendan T.
• Buckley, John

• Visual acuity (VA)
• Dynamic visual performance
• Walking-induced head motion
• Gaze assessment techniques
• Ageing
• Phone-reading performance
• Gaze orientation
• Locomotion
• Head kinematics
• Eye kinematics
• Assumed-gaze approach

Statement dc:rights

• <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/"><img alt="Creative Commons License" style="border-width:0" src="http://i.creativecommons.org/l/by-nc-nd/3.0/88x31.png" /></a><br />The University of Bradford theses are licenced under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/">Creative Commons Licence</a>.

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10454/20205

OAI identifier oai:identifier

oai:bradscholars.brad.ac.uk:10454/20205