 Latency: this is the time taken from the appearance of a target to the beginning of a saccade in response to that target; Peak Velocity: this is the highest velocity reached during the saccade. Saccade velocity profiles are usually symmetrical at least for small and medium size saccades. In some conditions while the size of saccades remains reasonably accurate, the saccade velocity is greatly reduced - so-called slowed saccades; Precision: relation between angular displacement of the eye and the displacement of the reference target; The optokinetic reflex causes eye movement in response to objects moving in the periphery while the head is stationary and is extremely important for stabilizing the image of visual input on the retina and provides for primary control of this capacity when the head is stationary. It is composed by a slow phase SP, directed toward the movement of the panorama, and a quick phases QP with opposite direction. These movements have similar characteristics to saccadic eye movements. 