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Efficiently Recording the Eye-Hand Coordination to Incoordination Spectrum
Published on: March 21, 2019
The functional consequences of glaucoma for eye-hand coordination.
Aachal Kotecha1, Neil O'Leary, Dean Melmoth
1Department of Optometry and Visual Sciences, City University, London, United Kingdom. aachalkotecha@gmail.com
Investigative Ophthalmology & Visual Science
|September 23, 2008
Summary
Glaucoma patients show impaired visually guided reaching and grasping (prehension) due to slower movement planning and execution. These deficits correlate with visual field loss and reduced stereoacuity, impacting eye-hand coordination.
Area of Science:
- Ophthalmology
- Neuroscience
- Biomechanics
Background:
- Glaucoma is a progressive optic neuropathy leading to visual field loss.
- Visually guided reaching and grasping (prehension) are complex sensorimotor tasks crucial for daily activities.
- Previous research has not fully elucidated the impact of glaucoma on prehension kinematics.
Purpose of the Study:
- To investigate differences in prehension behavior between glaucoma patients and normally sighted controls.
- To assess the relationship between visual field sensitivity and prehension deficits in glaucoma.
Main Methods:
- 16 glaucoma patients and 16 controls performed reaching-and-grasping tasks under various viewing conditions.
- 3D motion capture recorded hand movements, quantifying prehension planning, execution, and control.
- Visual fields (VF), stereoacuity, and movement kinematics were measured and analyzed.
Main Results:
- Glaucoma patients exhibited significant delays in movement onset (approx. 100 ms) and overall movement time (approx. 140 ms) compared to controls.
- Reaching movements were more tentative in glaucoma patients, correlating with visual field severity and stereoacuity deficits.
- No significant differences in grasping kinematics were observed between groups.
Conclusions:
- Glaucoma patients demonstrate impaired eye-hand coordination, specifically in the reaching phase of prehension.
- Deficits in prehension are linked to the extent of visual field loss and reduced stereoacuity.
- Further research should explore how specific visual field defect locations influence prehension.
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