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dc.contributor.advisorElliott, David
dc.contributor.advisorBuckley, John
dc.contributor.authorVale, Anna*
dc.date.accessioned2011-07-06T10:35:00Z
dc.date.available2011-07-06T10:35:00Z
dc.date.issued2011-07-06
dc.identifier.urihttp://hdl.handle.net/10454/4931
dc.description.abstractImpairment of stereoacuity is common in the elderly population and is found to be a risk factor for falls. The purpose of these experiments was to extend knowledge regarding impairment of binocular vision and adaptive gait. Firstly using a 3D motion analysis system to measure how impairment of stereopsis affected adaptive gait during a negotiation of a step, secondly by determining which clinical stereotest was the most reliable for measuring stereoacuity in elderly subjects and finally investigating how manipulating the perceived height of a step in both binocular and monocular conditions affected negotiation of a step. In conditions of impaired stereopsis induced by acutely presented monocular blur, both young and elderly subjects adopted a safety strategy of increasing toe clearance of the step edge, even at low levels of monocular blur (+0.50DS) and the effect was greater when the dominant eye was blurred. The same adaptation was not found for individuals with chronic monocular blur, where vertical toe clearance did not change but variability of toe clearance increased compared to full binocular correction. Findings indicate stereopsis is important for accurately judging the height of a step, and offers support to epidemiological findings that impaired stereoacuity is a risk for falls. Poor agreement was found between clinical stereotests. The Frisby test was found to have the best repeatability. Finally, a visual illusion that caused a step to be perceived as taller led to increased toe elevation. This demonstrates a potential way of increasing toe clearance when stepping up and hence increase safety on stairs.en_US
dc.language.isoenen_US
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>.en_US
dc.subjectFallsen_US
dc.subjectAdaptive gaiten_US
dc.subjectStair negotiationen_US
dc.subjectBinocular visionen_US
dc.subjectAnisometropiaen_US
dc.subjectMonovisionen_US
dc.subjectStereopsisen_US
dc.subjectMonocular cuesen_US
dc.subjectStereoacuityen_US
dc.subjectElderlyen_US
dc.subjectRisk factorsen_US
dc.titleThe Effects of Binocular Vision Impairment on Adaptive Gait. The effects of binocular vision impairment due to monocular refractive blur on adaptive gait involving negotiation of a raised surface.en_US
dc.type.qualificationleveldoctoralen_US
dc.publisher.institutionUniversity of Bradfordeng
dc.publisher.departmentDepartment of Optometryen_US
dc.typeThesiseng
dc.type.qualificationnamePhDen_US
dc.date.awarded2009
dc.description.publicnotesThe Study data files are unavailable online.en
refterms.dateFOA2018-07-19T05:35:03Z


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