Flicker and Color Adaptation in the Human Electroretinogram

Abstract

Flickering ten millisecond light stimuli have been used to elicit the human electroretingram under conditions of chromatic adaptation. The resulting records have been examined both for participation of photopic and scotopic mechanisms, and for selective wavelength effects. With slowly flickering stimuli (4 flashes per second) the ERG (electroretinogram) exhibited distinct photopic and scotopic components even when recorded from eyes that were well light adapted. More rapidly flickering stimuli (20 flashes per second) elicited pre-eminently photopic potentials. It was found that the adaptation stimuli, depending upon their color, were effective in reducing the sensitivity of one or the other component, but that specific chromatic effects within either component were quite small. The results are discussed in relation to psychophysical data and earlier ERG experimentation.