The major elevator of the upper eyelid is the levator palpebrae muscle, which is skeletal muscle innervated by lower motor neurons in the oculomotor nucleus that travel in the oculomotor nerve. A minor elevator of the upper eyelid is the superior tarsal muscle, which is smooth muscle innervated by orbital sympathetic axons that travel the same pathway as the sympathetic axons that control iris dilation. Weakness of upper eyelid elevation is called ptosis, which may occur with dysfunction of either muscle, but is usually more severe with levator palpebrae dysfunction.

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Level 3 Unit 2 Part 43: Higher functional neuroanatomy