Saccadic Suppression of Image Displacement

Saccadic suppression of image displacement (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 or blink 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 the human 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).