Saccadic Suppression of Image Displacement
or SSID, is the phenomenon in visual perception
where the brain selectively blocks visual processing during eye movements
in such a way that large changes in object location in the visual scene during a saccade
are not detected.
The phenomenon described by Bridgeman et al. (Bridgeman, G., Hendry, D., & Stark, L., 1975) is characterized by the inability to detect changes in the location of a target when the change occurs immediately before, during, or shortly after the saccade, following a time course very similar to that of the suppression of visual sensitivity, with a magnitude perhaps even more striking than that of visual sensitivity (4 log units vs. 0.5-0.7 log units (Bridgeman et al., 1975; Volkmann, 1986)).
These results indicate that our perceptual system neglects many useful pieces of information when it comes to spatially localizing target displacements occurring during a saccade. Surprisingly, in contrast to the perceptual system, the motor system is able to access precise spatial information in order to render precise motor actions during a Saccade (Bridgeman, Lewis, Heit, & Nagle, 1979; Prablanc & Martin, 1992).
Eliminating the suppression of image displacement - or the Blanking Effect
If a target which is displaced during a saccade is not present at the end of the saccade, but reappears a short time later after a blank interval, subjects are able to regain the ability to successfully detect whether... Read More