Which cranial nerve controls eye movement?

The cranial nerve responsible for controlling most eye movements is cranial nerve III, also known as the oculomotor nerve. This nerve innervates several extraocular muscles, including the medial rectus, superior rectus, inferior rectus, and inferior oblique, all of which are essential for moving the eye in various directions, such as upward, downward, and inward.

Cranial nerve III also plays a role in controlling the pupil's constriction and maintaining eyelid elevation. Its proper functioning is crucial for coordinated eye movement and maintaining visual acuity. Dysfunction of the oculomotor nerve can lead to symptoms such as ptosis (drooping of the eyelid), diplopia (double vision), and difficulty in eye movements.

While cranial nerves IV and VI are also involved in eye movement, they target different extraocular muscles. Cranial nerve IV, or the trochlear nerve, controls the superior oblique muscle, which allows for the depression and internal rotation of the eye. Cranial nerve VI, the abducens nerve, innervates the lateral rectus muscle, responsible for abduction of the eye. Although they contribute to eye movement, they do not control the majority of eye motions as cranial nerve III