Point 21 Intro Pathway Deficit Clinical Overview Problems Contents Anatomy

Point 21. Occulomotor Nuclear Complex (CN III) The oculomotor nucleus proper is comprised of cells that innervate all extraocular eye muscles except the lateral rectus (LR6) and superior oblique (SO4). Remember that it also innervates the levator palpebrae. The EDINGER-WESTPHAL nucleus, which lies dorsal to the oculomotor nucleus proper, contains preganglionic parasympathetic (visceromotor) neurons whose axons end in the ciliary ganglion. Short postganglionic parasympathetic axons then pass from the ciliary ganglion to the sphincter pupillae of the iris and the ciliary muscles of the eye (for changing shape of lens in accommodation). Input to the Edinger­Westphal nucleus arises from a cell group called the pretectum, a cell complex that receives retinal input and is part of the pathway involved in reducing the size of the pupil upon light stimulation of the retina. Don't worry about the pretectum now!