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Related Experiment Video

Updated: Apr 1, 2026

Development of a Gaze-Contingent Display Framework Designed for Perceptual and Oculomotor Research with Simulated Central Vision Loss

Development of a Gaze-Contingent Display Framework Designed for Perceptual and Oculomotor Research with Simulated Central Vision Loss

Published on: April 11, 2025

Functional Vision Disorder.

Robert A Egan¹, W Curt LaFrance²

¹Oregon Neurology, Portland, Oregon.

Seminars in Neurology

|October 8, 2015

Summary

Functional vision disorder (FVD) involves visual symptoms like vision loss and double vision. Manual perimetry can detect functional visual loss, and neuropsychiatric interventions may help manage FVD.

Area of Science:

Neurology
Ophthalmology
Neuro-ophthalmology

Background:

Functional vision disorder (FVD) is frequently encountered in neurologic and ophthalmologic practices.
It can manifest independently or alongside other medical conditions.
Symptoms include vision loss, visual field deficits, diplopia, oscillopsia, anisocoria, blepharospasm, and ptosis.

Purpose of the Study:

To review the diagnostic approaches and potential therapeutic strategies for functional vision disorder.
To highlight the significance of manual perimetry in identifying functional visual loss.
To explore the underlying neuropathophysiologic mechanisms and the role of neuropsychiatric factors.

Main Methods:

Review of existing literature on functional vision disorder.

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Last Updated: Apr 1, 2026

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Analysis of diagnostic findings, particularly from manual perimetry.

Examination of studies on neuropsychiatric factors in conversion disorders.

Main Results:

Manual perimetry is crucial for diagnosing functional visual loss.
The presence of a central scotoma on visual field testing strongly suggests a neuropathophysiologic process.
The precise mechanisms of FVD remain unclear, but links to neuropsychiatric elements are suggested.

Conclusions:

Functional vision disorder presents with diverse visual and oculomotor symptoms.
Manual perimetry is a key diagnostic tool for identifying functional visual loss.
Psychological and psychiatric interventions show promise in managing FVD patients.