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Updated: Jun 1, 2026
09:49
Methods to Explore the Influence of Top-down Visual Processes on Motor Behavior
Published on: April 16, 2014
Perimetry and visual psychophysics
1Departments of Ophthalmology and Neurology, University of Iowa, Iowa City, IA, United States.
Handbook of Clinical Neurology
|May 30, 2026
Summary
Visual field testing, or perimetry, maps vision loss patterns to pinpoint neurologic damage. Understanding these patterns aids in diagnosing conditions affecting the visual system and brain.
Area of Science:
- Neuroscience
- Ophthalmology
- Clinical Neurology
Background:
- Visual field defects are critical indicators for localizing neurological damage within the sensory visual system.
- Different patterns of visual loss correspond to specific anatomical locations, from the optic nerve to the occipital cortex.
Purpose of the Study:
- To elucidate the relationship between visual field defect patterns and the anatomic localization of lesions.
- To provide a comprehensive overview of perimetric testing, its interpretation, and its application in neurologic diagnosis.
Main Methods:
- Discussion of various perimetric testing methodologies and their psychophysical underpinnings.
- Analysis of visual field patterns associated with lesions at different points in the visual pathway (prechiasmal, optic chiasm, optic tract, occipital cortex).
- Review of relevant visual system anatomy and interpretation of perimetric results for localization.
Main Results:
- Monocular visual defects indicate prechiasmal damage.
- Bitemporal hemianopia is characteristic of optic chiasm lesions.
- Incongruous homonymous hemianopia suggests optic tract damage, with increasing congruity indicating more posterior lesions approaching the occipital cortex.
Conclusions:
- Recognizing specific visual field loss patterns is essential for accurate neurologic localization.
- Perimetry is a valuable clinical tool for quantifying visual function and diagnosing visual pathway disorders.
- Systematic interpretation of perimetric data, combined with anatomical knowledge, enhances diagnostic capabilities.
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