RECEPTOR AND NEURAL VISUAL READAPTATION AFTER EXPOSURE TO COLORED FLASH

The time needed to recover optokinetic nystagmus or electroretinograph y complexes after a glare inducing flash was measured to study the rec eptor and neural visual readaptation, Electroretinographs and optokine tic nystagmus were evoked with low intensity stimuli. The light from a flash tube was filtered with an interference filter (T-max = 536 or 6 22 nm) and evenly distributed into a Goldmann hemisphere observed by t he subject. The recovery of the amplitude of the a-wave of the electro retinography is quicker than the recovery of optokinetic nystagmus aft er a low intensity glare inducing flash. The recovery time was shorter for a red than for a green flash of equivalent dose for both recovery modalities. The time difference between electroretinography a-wave an d optokinetic nystagmus recovery was the same and independent of glare inducing flash wavelength. The recovery of the amplitude of the a-wav e of the electroretinography was quicker than the recovery of optokine tic nystagmus after a low intensity glare inducing flash. This time di fference between the recovery modalities may in part be due to the dif ference between the physiological stimuli used, but it is believed tha t most of the time difference is because the recovery of optokinetic n ystagmus monitors more of the afferent visual pathway with complex pos t receptor neural mechanisms than the recovery of the a-wave.