Exploring Visual Adaptation at High Intensity Levels with a Flash-Probe Paradigm
Abstract
We have studied the effect of pulsed, high-intensity, periodic backgrounds on light adaptation. For this we have used a flash-probe paradigm involving the measurement of thresholds for detecting probe stimuli presented at various phases against a modulated adapting background consisting of brief intense light flashes. We have varied the frequency of the background from 1 Hz to 64 Hz while keeping the average intensity of the background modulation constant. We have utilized state-of-the art high-intensity white light emitting diodes to enable measurements at time-average adapting intensities greater than 106 td, several orders of magnitude higher than previous workers. The aim of the study was to investigate the temporal dynamics of light adaptation processes that occur when the eye is exposed to a train of discrete high intensity flashes of light. In addition, we attempt to draw some qualitative comparisons with existing data from the probe sinewave paradigm. Overall, despite the experimental differences, summary measures derived from the flash-probe data set are remarkably similar to those measured using the probe-sinewave technique.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2008
- Accession Number
- ADA487981
Entities
People
- Bret Z. Rogers
- Laura E. Barnes
- Leon N. McLin
- Peter A. Smith
Organizations
- Northrop Grumman