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Updated: Jun 5, 2026
06:25
Motion-Acuity Test for Visual Field Acuity Measurement with Motion-Defined Shapes
Published on: February 23, 2024
What drives adaptive gait changes to acutely presented monocular blur?
Graham J Chapman1, Andy Scally, David B Elliott
1Centre for Health, Sport and Rehabilitation Research, University of Salford, Salford, United Kingdom. g.j.chapman@salford.ac.uk
Summary
Gait changes in older adults from blurred vision were driven by lens magnification, not safety. Positive lenses made steps seem closer and larger, while negative lenses made them appear further and smaller.
Area of Science:
- Ophthalmology
- Biomechanics
- Gerontology
Background:
- Monocular spherical lens blur can alter gait in older adults.
- Previous research suggested these gait changes were a safety strategy.
Purpose of the Study:
- To investigate if gait alterations from monocular spherical lens blur are a safety strategy or due to lens magnification.
- To differentiate between adaptive gait responses and magnification effects.
Main Methods:
- 10 older adults (mean age 74.9 years) underwent gait and visual function tests.
- Monocular blur was induced using ±1.00 DS and ±2.00 DS lenses on the dominant eye.
- Adaptive gait (foot position, toe clearance) and visual acuity, contrast sensitivity, and stereoacuity were measured.
Main Results:
- Positive and negative spherical lens blur induced distinct stepping strategies.
- Positive lenses increased toe clearance and reduced lead foot distance on the surface.
- Negative lenses caused opposite effects on gait parameters.
Conclusions:
- Gait adjustments were driven by lens magnification, not safety.
- Positive lenses simulated closer, larger steps; negative lenses simulated further, smaller steps.
- Findings challenge previous notions of gait changes as solely safety-driven and have implications for prescribing lenses to older adults.
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