The long ciliary nerves are branches of the nasociliary nerve, which is a part of the trigeminal nerve (cranial nerve V). These nerves primarily provide sensory innervation to the cornea, sclera, and parts of the conjunctiva, playing a crucial role in the eye's ability to sense touch and pain. In addition to sensory functions, the long ciliary nerves also carry sympathetic fibers that help regulate the size of the pupil and the production of aqueous humor. This dual role is essential for maintaining proper eye function and responding to environmental changes.