ABSTRACT
The purpose of eye movements is either gaze stabilization, in which the eyes remain fixated on an object during rotation of the head, or gaze shifting which allows the central part of the retina, the fovea, to be brought to bear on an object, or track a moving object. Gaze stabilization is controlled by the vestibulo-ocular and optokinetic systems. Rapid head rotation, detected by the semi-circular ducts provides input for vestibulo-ocular reflexes (VOR), whereas optokinetic reflexes depend on visual input to monitor slow head rotations. Gaze stabilization is controlled by the vestibulo-ocular and optokinetic systems. Rapid head rotation, detected by the semi-circular ducts provides input for VOR, whereas optokinetic reflexes depend on visual input to monitor slow head rotations. Each eye is moved by three pairs of extraocular eye muscles. Two pairs of rectus muscles (superior and inferior, medial and lateral) originate from a common annular tendon attached at the back of the orbit.
