Psychiatric-Mental Health Nurse Practitioner Exam

Which cranial nerve is responsible for eye movement?

1. Optic

2. Oculomotor

3. Trigeminal

4. Abducens

The correct answer is: Oculomotor

The cranial nerve responsible for eye movement is the oculomotor nerve. This nerve primarily controls most of the eye's movements, including the constriction of the pupil and maintaining an open eyelid. It innervates several extraocular muscles, which are crucial for moving the eyeball in various directions, including up, down, and medial movements. Additionally, the oculomotor nerve plays an important role in the autonomic regulation of pupil size, responding to light and accommodation. While there are other cranial nerves that also contribute to eye movement, such as the abducens and the trochlear nerves, the oculomotor nerve is the main nerve involved in a wide range of eye movements. The optic nerve is primarily responsible for vision, and the trigeminal nerve is mainly associated with sensation in the face and motor functions such as biting and chewing. Understanding the roles of these cranial nerves is essential for recognizing their individual contributions to ocular function and overall neurological health.