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Updated: Jun 27, 2026
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Assessing Binocular Central Visual Field and Binocular Eye Movements in a Dichoptic Viewing Condition
Published on: July 21, 2020
Gait alterations negotiating a raised surface induced by monocular blur
Anna Vale1, John G Buckley, David B Elliott
1Department of Optometry, Division of Medical Engineering, School of Engineering, Design and Technology (JGB), University of Bradford, Bradford, United Kingdom. a.vale@bradford.ac.uk
Summary
Even slight monocular blur significantly alters elderly gait when stepping over obstacles. This suggests impaired stereopsis (3D vision) affects balance and fall risk, necessitating further research into chronic blur effects.
Area of Science:
- Gerontology
- Vision Science
- Biomechanics
Background:
- Falls are a major cause of injury and mortality in the elderly.
- Impaired stereopsis (3D vision) is a potential risk factor for falls, but epidemiological data are inconsistent.
- Laboratory studies indicate stereoacuity is crucial for adaptive gait.
Purpose of the Study:
- To investigate the impact of acute stereopsis impairment via monocular blur on elderly gait.
- To assess gait changes when negotiating a raised surface under varying levels of monocular blur (0.50D to monovision correction).
Main Methods:
- Eleven elderly subjects (mean age 73.3 years) performed gait tasks over a raised surface.
- Nine visual conditions were tested: binocular, monocular occlusion, and monocular blur (0.50D, 1.00D, monovision).
- Analysis focused on foot positioning and toe clearance parameters, with blur applied to dominant or non-dominant eyes.
Main Results:
- Monocular blur significantly impaired stereopsis (p < 0.01).
- All levels of monocular blur, including 0.50D, increased lead limb toe clearance (p = 0.03).
- Monovision correction resulted in toe clearance similar to monocular occlusion.
Conclusions:
- Even minor monocular blur alters gait when navigating obstacles, indicating an effect on height judgment.
- Acute monocular blur impacts the ability to accurately assess step height.
- Further research is needed to understand adaptations in individuals with chronic monocular blur.
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