Saccadic Supression during Reading Activities

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Cognitive suppression during saccades and eye movement research

The foveal high acuity vision corresponding to the center of our gaze is confined to a relatively small retinal area encompassing approximately 3 degrees of central vision. This anatomical limitation of our visual perception requires saccades, ballistic jerky eye movements from point to point in space for fine details to be resolved.

Saccades occur several times a second (every 250-300 ms) and generally have duration of between 30 and 100 ms during reading, depending on the distance the movement covers (see e.g. Rayner, 1998).

During a saccadic eye movement, visual sensitivity is greatly reduced, thereby confining the vast majority of visual perception to the fixations. Because of this phenomenon called saccadic (visual) suppression, we are unaware of blurred motion images produced by saccades and are not disturbed by them. Researchers have been interested in whether higher-level cognitive processing might also be suppressed during saccades.