Which reflex is responsible for maintaining an image on the fovea with prolonged head movements (>30 seconds)?

• A. Optokinetic reflex (OKR)
• B. Vestibulo-ocular reflex (VOR)
• C. Oculomotor reflex
• D. Pursuit reflex

Answer: (A)

When head movement is slow and sustained, the entire visual scene sweeps across the retina. The brain uses the optokinetic reflex to keep that scene steady on the fovea by producing a slow eye movement that follows the motion of the entire visual field, with a quick reset saccade to prevent drift. This slow, field-driven response is well-suited for prolonged head movements, helping maintain a stable image on the fovea even as the head continues to move for many seconds. The vestibulo-ocular reflex, by contrast, handles rapid head turns and can diminish in effectiveness during long, steady motion; pursuit requires a distinctly moving target; the specific oculomotor reflex here isn’t the primary mechanism for wide-field stabilization.