Certified Rehabilitation Registered Nurse (CRRN) Practice Exam

Which cranial nerves are responsible for eye movement?

1. Olfactory, trigeminal, and facial

2. Oculomotor, abducens, and trochlear

3. Optic, vestibulocochlear, and hypoglossal

4. Vagus, glossopharyngeal, and accessory

The correct answer is: Oculomotor, abducens, and trochlear

The cranial nerves that are responsible for eye movement are the oculomotor, abducens, and trochlear nerves. Each of these nerves plays a specific role in controlling different muscles that facilitate eye movement. The oculomotor nerve is primarily responsible for the majority of eye movements, including raising the eyelid and constricting the pupil. It innervates most of the extraocular muscles, which are crucial for coordinated and precise eye movements. The abducens nerve controls lateral movement of the eye, specifically innervating the lateral rectus muscle, which allows the eye to move outward, away from the midline. This is essential for ensuring that both eyes can work together effectively during lateral gaze. The trochlear nerve innervates the superior oblique muscle, which is responsible for turning the eye downward and laterally. This function is important for looking down and out, and its unique pathway through the brain makes it the only cranial nerve that emerges from the posterior aspect of the brainstem. Collectively, these three nerves ensure that the eyes can move properly in various directions, contributing to visual tracking and coordination. Understanding their function is crucial for assessing visual and neurological health. The other groups of cranial nerves listed do not