Luminance-unbalanced pattern onset-offset electroretinogram and visual evoked cortical potential

Abstract

The effects of a luminance-unbalanced pattern onset-offset mode of stimulation on electroretinograms and visual evoked cortical potentials were investigated. With the use of originally devised software, only offset luminance was varied from 14.7 to 62.3 cd/m2. A vertical grating pattern (1.5 c/deg, 38.8 cd/m2 mean luminance, 0.95 contrast) was presented for 260 ms and was absent for 260 ms to normal subjects. With an increase in the luminance level of the offset pattern from the lowest level, the amplitude of the onset electroretinogram increased by degrees, while that of the offset electroretinogram gradually decreased. Conversely, onset visual evoked cortical potential responses decreased gradually, and offset visual evoked cortical potentials increased correspondingly. Furthermore, the spatial tuning of the onset pattern electroretinogram was already ambiguous, even when there was only a 4-cd/m2 difference between onset and offset pattern luminances. Thus, luminance control is indispensable for pattern onset-offset stimulation.

Visual Function and Gene Analysis in a Family with Oguchi’s Disease

“…A bipolar contact lens electrode was utilized and an earth electrode was placed at the right outer canthus. P-ERG and P-VECP were simultaneously recorded according to the method that we previously reported elsewhere [6].…”

Pattern Electroretinogram Elicited by a Dartboard Pattern

“…Thus, a larger check size and a higher mean luminance setting are not recommended for studying the visual function in various eye diseases with respect to the contrast-related response. However, there is a disadvantage to use of pattern onset-offset stimulation, because luminance control is very difficult to maintain between the two patterns [6].…”