The oculomotor nerve is associated with how many functions?

The oculomotor nerve, which is the third cranial nerve, is responsible for several crucial functions related primarily to eye movement. Specifically, it innervates four of the six extraocular muscles: the superior rectus, medial rectus, inferior rectus, and inferior oblique. These muscles are essential for various eye movements, such as looking up, down, and inward.

In addition to motor functions, the oculomotor nerve also has parasympathetic functions. It controls the constriction of the pupil through the iris sphincter muscle and adjusts the lens shape for accommodation through the ciliary muscle, enabling the eye to focus on objects at varying distances.

These functions together sum up to three distinct roles or functions attributable to the oculomotor nerve: controlling eye movements, regulating pupil size, and facilitating lens accommodation. This comprehensive involvement with both voluntary and involuntary eye actions solidifies its classification as having three primary functions.