Mechanisms of Elementary Eye Movements as a Tracking System

In the study of eye-movement mechanisms, the most prevalent hypotheses are those that explain these mechanisms as a programmed system. The assumption is that before the eye accomplishes any movement, a program must be constituted in a control center to define the characteristics of the movement. It is claimed that programming governs all aspects of the oculomotor system: those determining the path of the gaze, that is, the route followed in observing objects, and those controlling elementary movements. For example, it is assumed that before the eye makes a saccade from one fixation point to another, a program should already have been compiled defining the direction, amplitude, and speed of this signal. This program is formed in the latency period preceding the saccade.