Is eccentric fixation a monocular or binocular phenomenon?

Is eccentric fixation a monocular or binocular phenomenon?

• A. Monocular
• B. Binocular
• C. Both
• D. Neither

Answer: (A)

Eccentric fixation occurs when a non-foveal retinal point is used for fixation, usually because the fovea of one eye is damaged. This adaptation is specific to one eye, so it is a monocular phenomenon. In normal binocular viewing, the fellow eye can still fixate with its fovea and the brain fuses inputs from both eyes, so the fixation shift in the affected eye doesn’t represent a binocular fixation strategy. If both eyes were damaged and adopted eccentric points, you could see bilateral eccentric fixation, but the typical situation is monocular.

Eccentric fixation occurs when a non-foveal retinal point is used for fixation, usually because the fovea of one eye is damaged. This adaptation is specific to one eye, so it is a monocular phenomenon. In normal binocular viewing, the fellow eye can still fixate with its fovea and the brain fuses inputs from both eyes, so the fixation shift in the affected eye doesn’t represent a binocular fixation strategy. If both eyes were damaged and adopted eccentric points, you could see bilateral eccentric fixation, but the typical situation is monocular.