Ocular Motor Function and Eye Movement Quiz

Ocular Motor Function and Eye Movement Summary

• Ocular movement occurs around three axes: x for vertical eye movements, y for cyclorotational eye movements, and z for horizontal eye movements.
• The field of fixation is around 40-50°, with typical eye movements around 15° in magnitude.
• Saccadic eye movements are fast, leaping movements occurring at about 400-700 degrees/second, with most movements taking about 300 milliseconds.
• Saccadic eye movements are used in sampling the visual environment, such as in reading, driving, and perceiving threats.
• Smooth pursuit eye movements maintain stability of an object on the retina and typically do not exceed about 40° per second, observed by tracking a moving target.
• The vestibular and optokinetic systems work to maintain a stable retinal image during head movements, with different sensory signals generating compensatory eye movements.
• Methods to measure eye movements include direct observation, EOG, infra-red reflection, scleral search coil, Purkinje eye tracker, and video systems.
• The EOG records eye position using electrodes attached to the face, while the search coil method recorder measures eye movement using a coil embedded in a contact lens annulus.
• Infra-red reflection methods detect reflected infra-red light from the anterior eye by sensors mounted onto spectacle frames, proportional to the eye movement.
• The presentation encourages questions via Brightspace discussion board or the chat function on Teams.