We explore our visual world by making series of saccades. Saccades are very rapid eye movements (50-60ms) that displace the line of sight from one point to another. This has been very nicely demonstrated by a Russian scientists named Alfred L. Yarbus, who built a device to record eye movements (His book is available here). While looking at a face picture for several seconds, humans perform a series of saccades and scan the entire picture (right panel).
During a saccade, there is a minimum perception of the visual world. Therefore, the part of the visual world that is projected onto the retina (i.e. that is perceived) is very different before and after a saccade. Despite that difference, we do perceive a very stable world. We are even unaware of those eye movements. In this post, I will describe the mechanisms that allow us to perceive a stable visual world.
written by Jean-Jacques Orban de Xivry
Scientist in the motor control field.