Eye Controlled Simulation of Scotomas on the Retina
Abstract
A scotoma simulation system was developed to approximate the visual losses which might be expected as an aftereffect of laser exposure. The scotomas or visual blindspot were generated using eye controlled displays which moved a masking blindspots with the subjects eye movements during visual performance tasks. These eye controlled scotoma movements eliminated the central vision in these normal subjects during the experimental sessions in the same way that retinal damage from chronic or acute laser exposure might reduce central retinal visual sensitivity. Measures of fixation stability were taken during scotoma simulation while the subjects attempted to maintain an acuity target near the fovea. The presence of a simulated scotoma caused grossly distorted eye fixation patterns when compared to normal fixation control. Abnormal patterns were reduced as subjects became more experienced with the simulated visual losses. Visual losses due to immediate versus long term laser aftereffects were addressed in the development of both positive scotoma (afterimages) and negative scotoma simulations. The general method of scotoma simulation has value because it allows testing of the effects of the size, position and shape of scotomas in normal subjects under complete safety. Keywords: Laser damage, Focusing, Adaptive training.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1987
- Accession Number
- ADA202903
Entities
People
- James H. Bertera
Organizations
- Smith-Kettlewell Eye Research Institute