Do Disappearance Patterns in Low Illumination constitute a Perceptual Phenomenon or a Response Artefact?

Abstract

IF a dimly illuminated target is steadily fixated in a darkened room, all or parts of the target may seem to disappear and then reappear. There have been several reports that such disappearances are “structured” or “meaningful”^1–3. For example, whole lines presumably tend to disappear and reappear as units. Such “structured” disappearances have also been reported in stabilized retinal image and after-image conditions⁴. Hebb interpreted the seeming ubiquity of whole line disappearances as support for the idea that the whole line is a basic perceptual “unit” in complex visual percepts.