The Retinal Image is Unstable

“The Retinal Image is Unstable

Matters are made worse by the fact that the eyes move almost continuously. Several times a second they jitter and bounce; they also make saccades and micro-saccades-that is, sharp, ballistic movements. As a result, the projection of an object you perceive to be still in facts jumps around on your eyeball, and when you track a moving object, its image stays still on your retina while that of the stationary background races across your eyes. Again, in order to explain how we manage to experience a stable visual world, we need to suppose, it seems, that the ability is achieved at some later stage in the processing of the original retinal information.”

Alva Noë, p. 133-134, ‘Out of our heads’, Hill and Wang 2009

In his new book, Out of our heads, Alva Noë advocates a radical change in how we think of the consciousness and how to resolve the Cartesian dualistic dilemma. The above quote refers to the problems which arise when trying to explain the visual world as something separate from the perception of it. It also very neatly sums up the technical starting point for Saccadic Sightings.