Nature and Uses of Primary Data Sources Page 1 of 14 ______________________________________________________________________.
cranial nerve - any of the 12 paired nerves that originate in the brain stem. 1  nerve, nervus - any bundle of nerve fibers running to various organs and tissues of the body. 2  first cranial nerve, nervii olfactorii, olfactory nerve - a collective term for numerous olfactory filaments in the nasal mucosa.
The twelve cranial nerves, the trochlear nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral column. The trochlear nerve is the only cranial nerve that arises from the back of the brain stem and it follows the longest course within the skull of any of the cranial nerves.