ABSTRACT
Normal fixation is a complex neurological function. It is the direction of gaze that holds the visual image of the object of regard on the fovea. Some authors feel that the act of fixation represents a totally different system, an independent visual-fixation system, that has yet to be defined. Others feel that it is a form of smooth pursuit, an act that suppresses the image motion that would be present due to the natural drift of the eyes. There is also evidence that activity in the frontal eye fields and superior colliculus is responsible for suppressing saccades away from fixation when steady fixation is important, e.g. at times of concen tration. This becomes important in certain disease states that interrupt fixation.
