vestibuloocularreflexen

The vestibulo-ocular reflex (VOR) is a fast, reflexive mechanism that stabilizes images on the retina during head movements by producing compensatory, opposite-direction eye movements. This stabilization preserves visual clarity when the head moves.

Sensory input for the VOR comes from the vestibular apparatus of the inner ear, including the semicircular canals, utricle, and saccule. The semicircular canals detect angular head motion, while the otolith organs detect linear acceleration and head position relative to gravity. Hair cells transduce motion into neural signals that travel via the vestibular nerve (cranial nerve VIII) to the vestibular nuclei in the brainstem.

Neural processing integrates vestibular information with cerebellar input to produce precise eye movements. From the vestibular nuclei, motor commands travel through pathways to the extraocular muscles, mediated by cranial nerves III, IV, and VI, producing eye movements opposite to the direction of head movement. The cerebellum, particularly the flocculus and nodulus, calibrates and adapts the VOR to maintain gaze stability across different speeds and viewing distances.

Clinical relevance includes assessing vestibular function when gaze stabilization is impaired. Vestibular dysfunction can cause blurred vision or oscillopsia, especially with head movements. Diagnostic tools include the head impulse test, caloric testing, and rotational chair assessments. Rehabilitation strategies, such as vestibular rehabilitation therapy, aim to improve VOR function and reduce symptoms through targeted exercises and compensatory strategies.