How many nerves innervate the six extraocular muscles?

There are three cranial nerves that innervate the six extraocular muscles responsible for eye movement. These muscles include the superior rectus, inferior rectus, medial rectus, lateral rectus, superior oblique, and inferior oblique.

The cranial nerves involved are:

1. The oculomotor nerve (cranial nerve III), which innervates the superior rectus, inferior rectus, medial rectus, and inferior oblique.

2. The trochlear nerve (cranial nerve IV), which innervates the superior oblique.

3. The abducens nerve (cranial nerve VI), which innervates the lateral rectus.

Together, these three nerves coordinate the intricate movements of the eyes, enabling both conjugate (together) and disconjugate (independent) eye movements. Each of the six muscles plays a specific role in allowing the eye to position correctly in various directions, crucial for visual alignment and depth perception.