A model for the slow control system during monocular fixation.

A method has been developed to compare the behaviour of the oculomotor control system during steady fixation and during reactions on small stimulus movements. No difference between the two conditions was found, and the reactions on small steps (1-5') and step/ramps (2-10'/sec), during normal and stabilized vision, have been used to develop a model for the slow control system during fixation. The model consists of a position channel, which integrates the retinal error, and a velocity channel, that uses both the retinal velocity and an efferent copy of the eye velocity. The model parameters have been estimated from the data of four subjects.