Final answer:
Assessing extraocular eye movements checks the oculomotor, trochlear, and abducens cranial nerves, responsible for controlling the extraocular muscles involved in eye movement.
Step-by-step explanation:
Assessing extraocular eye movements checks the cranial nerves oculomotor, trochlear, and abducens. These are the third, fourth, and sixth cranial nerves respectively. The oculomotor nerve innervates most of the extraocular muscles along with the levator palpebrae superioris, which raises the eyelid. The trochlear nerve controls the superior oblique muscle, which assists with the intorsion and depression of the eye, particularly when the eye is in an adducted position. The abducens nerve innervates the lateral rectus muscle, which is responsible for abducting the eye. Coordination and proper function of these nerves can be examined by having the patient follow a visual target, like a pen tip, through their visual field, ending with a test for convergence and accommodation.