The olfactory nerve (I), actually composed of many small separate nerve fibers, passes through perforations in the cribiform plate part of the ethmoid bone. These fibers terminate in the upper part of the nasal cavity and function to convey impulses containing information about odors to the brain.

The optic nerve (II) passes through the optic foramen in the sphenoid bone as it travels to the eye. It conveys visual information to the brain.

The Oculomotor Nerve travel through the cavernous sinus into the superior orbital fissure, passing out of the skull into the orbit. These nerves control the small muscles that move the eye and also provide sensory innervation to the eye and orbit.

The trigeminal nerve - ophthalmic, maxillary and mandibular branches travel through the cavernous sinus into the superior orbital fissure, passing out of the skull into the orbit. These nerves control the small muscles that move the eye and also provide sensory innervation to the eye and orbit.

The abducens nerve travel through the cavernous sinus into the superior orbital fissure, passing out of the skull into the orbit. These nerves control the small muscles that move the eye and also provide sensory innervation to the eye and orbit.

The facial nerve enters the internal auditory canal in the temporal bone. The facial nerve then reaches the side of the face by using the stylomastoid foramen, also in the temporal bone. Its fibers then spread out to reach and control all of the muscles of facial expression. The vestibulocochlear nerve reaches the organs that control balance and hearing in the temporal bone, and therefore does not reach the external surface of the skull.

The vestibulocochlear nerve enters the internal auditory canal in the temporal bone. The facial nerve then reaches the side of the face by using the stylomastoid foramen, also in the temporal bone. Its fibers then spread out to reach and control all of the muscles of facial expression. The vestibulocochlear nerve reaches the organs that control balance and hearing in the temporal bone, and therefore does not reach the external surface of the skull.

The glossopharyngeal nerve

The spinal accessory nerve leaves the skull via the jugular foramen to enter the neck. The glossopharyngeal nerve provides innervation to the upper throat and the back of the tongue, the vagus provides innervation to the muscles in the voicebox, and continues downward to supply parasympathetic innervation to the chest and abdomen. The accessory nerve controls the trapezius and sternocleidomastoid muscles in the neck and shoulder.

The hypoglossal nerve exits the skull using the hypoglossal canal in the occipital bone and reaches the tongue to control almost all of the muscles involved in movements of this organ