While most nerves come from the spinal cord, 12 pairs of cranial nerves (CN I-XII) emerge directly from the brain and leave the cranial cavity through several foramina to innervate (mainly) the head and neck. All the nerves are associated with nuclei in the brainstem, except the olfactory nerve (CN I) which projects from the periphery into the olfactory bulb and the optic nerve (CN … Continue reading Cranial nerves