Visual Masking

In visual masking, a visual stimulus called the “target” becomes less visible due to interactions with other stimuli, called “masks.” The 19th century scientist S. Exner first discovered masking in the visual system. The birth of visual masking was an artifact in one of Exner's studies of consciousness. He had been trying to determine the shortest flash duration necessary for a bar of light to be visible. As a control condition, he presented two identical bars in different places of the visual field and at different times, expecting that they would be perceived as identical in appearance. Exner was surprised to find that this was not, in fact, so. Under certain specific timing conditions, the first bar was rendered invisible by the presentation of the ...